Juvenile Dermatomyositis and Polymyositis: Epidemiology, Pathogenesis, And Clinical Manifestations

8/17/2019 Juvenile Dermatomyositis and Polymyositis: Epidemiology, Pathogenesis, And Clinical Manifestations

1/14

30/04/16 1044uvenile dermatomyositis and polymyositis: Epidemiology, pathogenesis, and clinical manifestations

Página 1 ttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-derma…polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#

Official reprint from UpToDatewww.uptodate.com ©2016 UpToDate

AuthorsClare Hutchinson, MDCM, FRCPCBrian M Feldman, MD, MSc, FRCPC

Section EditorsThomas JA Lehman, MDMarc C Patterson, MD, FRACP

Deputy Editor Elizabeth TePas, MD, MS

Juvenile dermatomyositis and polymyositis: Epidemiology, pathogenesis, and clinical manifestations

All topics are updated as new evidence becomes available and our peer review process is complete.

Literature review current through: Mar 2016. | This topic last updated: Feb 08, 2016.

INTRODUCTION — Juvenile dermatomyositis (JDM) and juvenile polymyositis (JPM) are rare autoimmune myopathies

in childhood. JDM is primarily a capillary vasculopathy, whereas JPM involves direct T cell invasion of muscle fibers

similar to that seen in adult polymyositis (PM) [1,2]. However, as the diagnostic tools become more sophisticated (eg,

biopsies that demonstrate inclusion body myositis or inflammatory dystrophies, or autoantibodies that are markers of

particular types of myositis such as anti-signal recognition particle [SRP] and necrotizing myopathy), fewer patients are

diagnosed with JPM, calling into question whether JPM is a specific entity. (See "Clinical manifestations of

dermatomyositis and polymyositis in adults".)

The epidemiology, pathogenesis, and clinical manifestations of JDM and JPM are reviewed here. Diagnosis andtreatment of these disorders are discussed elsewhere. (See "Juvenile dermatomyositis and polymyositis: Diagnosis" an

"Juvenile dermatomyositis and polymyositis: Treatment, complications, and prognosis".)

EPIDEMIOLOGY — JDM is the most common idiopathic inflammatory myopathy of childhood, accounting for

approximately 85 percent of cases [3,4]. In population-based studies, JDM has a reported annual incidence that ranges

from two to four cases per one million children [5-9]. The peak incidence is from 5 to 10 years of age [8,9]. Girls are

affected more often than boys, with a two- to fivefold greater rate [7,8,10].

JPM occurs less frequently and accounts for only 3 to 6 percent of childhood idiopathic inflammatory myopathies [3,7].

PATHOGENESIS — JDM and JPM are thought to be autoimmune disorders. JDM is associated with systemic

vasculopathy. It is sometimes associated with occlusive arteriopathy and capillary necrosis that eventually lead tocapillary loss and tissue ischemia. Although the etiology remains unclear, it has been proposed that JDM and JPM are

caused by an autoimmune reaction in genetically susceptible individuals, possibly in response to infection or

environmental triggers such as prenatal exposure to tobacco smoke and particulate inhalants [11].

Genetic susceptibility — The occurrence of JPM and JDM in monozygotic twins and first-degree relatives in some

families suggests a genetic predisposition to these disor ders [12,13]. A genome-wide association study identified single

nucleotide polymorphisms in the alleles comprising the human leukocyte antigen (HLA) 8.1 ancestral haplotype (AH8.1

as a genetic risk factor associated with all myositis phenotypes including JDM [14].

Non-HLA-associated genes, including genetic polymorphisms in tumor necrosis factor-alpha (TNF-alpha) and interleuk

1 (IL-1) receptor antagonist, are known risk factors for the development of JDM and for a more severe presentation [15

17].

A significantly increased rate of autoimmune diseases, particularly systemic lupus erythematosus (SLE) and type 1

diabetes, is seen in family members of children with JDM [18]. Higher levels of interferon-alpha (IFN-alpha) were seen

children with JDM who had family members with SLE, suggesting a shared predisposing factor.

Immunologic mechanisms — The following findings support the role of the immune system in the pathogenesis of

JDM and JPM:

®

®

http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/15-17http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/15-17http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/15-17http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/15-17http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/12,13http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/11http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/7,8,10http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/3,4http://www.uptodate.com.pbidi.unam.mx:8080/contents/clinical-manifestations-of-dermatomyositis-and-polymyositis-in-adults?source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/clinical-manifestations-of-dermatomyositis-and-polymyositis-in-adults?source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/clinical-manifestations-of-dermatomyositis-and-polymyositis-in-adults?source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/1,2http://www.uptodate.com.pbidi.unam.mx:8080/home/editorial-policyhttp://www.uptodate.com.pbidi.unam.mx:8080/home/editorial-policyhttp://www.uptodate.com.pbidi.unam.mx:8080/home/editorial-policyhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/18http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/15-17http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/14http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/12,13http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/11http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/3,7http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/7,8,10http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/8,9http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/5-9http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/3,4http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-treatment-complications-and-prognosis?source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-diagnosis?source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/clinical-manifestations-of-dermatomyositis-and-polymyositis-in-adults?source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/1,2http://www.uptodate.com.pbidi.unam.mx:8080/home/editorial-policyhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/contributorshttp://www.uptodate.com.pbidi.unam.mx:8080/


2/14



Infection — Several observations have suggested that JDM may develop as an unusual response to infection in a

genetically susceptible host:

T cell invasion of muscle fibers in patients with JPM [1].!

Epitopes that are common both to human skeletal muscle and the bacterium Streptococcus pyogenes are targets

for cytotoxic T cell responses in patients with early, active JDM, indicating a possible link between an immune

response to bacteria and the development of myositis [19].

!

Increased mast cell numbers in the skin and mature plasmacytoid dendritic cells in both muscle and skin in

patients with JDM [20].

!

Antinuclear antibodies (ANAs) are present in approximately 70 percent of patients with JDM and JPM. The specif

antigen(s) for these antibodies have not yet been identified [21].

!

Myositis-specific autoantibodies (MSAs) are found in a significant minority of adults with dermatomyositis (DM) an

polymyositis (PM) and are associated with specific clinical subgroups. MSAs were initially identified in only a sma

number of children with inflammatory myopathy [22,23]. In one study of 38 children with JDM and other connectiv

tissue diseases, for example, MSAs were identified in 12 of 77 serum samples [22]. In a second study, MSAs

(specifically anti Mi-2 autoantibodies) were found in only 2 of 42 patients with JDM. However, some of the

subsequently recognized MSAs are more commonly found in children with JDM. A study of 116 children registere

in the UK and Ireland JDM National Registry and Repository showed a 23 percent prevalence of anti-p155/140

antibodies; children with positive antibodies had more extensive skin disease [24]. (See "Clinical manifestations o

dermatomyositis and polymyositis in adults", section on 'Myositis-specific autoantibodies' and 'Cutaneous

manifestations' below.)

Anti-melanoma differentiation-associated gene 5 antibodies are associated with the occurrence of interstitial lung

disease in patients with JDM [25]. Appearance of these antibodies may precede clinical signs of interstitial lung

disease. (See 'Pulmonary involvement' below.)

!

Similarity of observed histologic changes between JDM and chronic graft-versus-host disease. The presence of

persistent maternal cells (maternal microchimerism), which triggers an immunologic response, was proposed as a

common pathogenetic pathway for the two disorders. Two studies have reported evidence of maternal

microchimerism in the peripheral blood and muscle biopsies of boys with juvenile inflammatory myopathy [26,27].

!

Experimental data demonstrating increased T cell reactivity of in vitro peripheral blood mononuclear cells to heat

shock protein (HSP) 60 in patients compared with normal controls [28]. HSPs are proposed to have a regulatory

role in chronic inflammatory diseases and may be an autoantigen for these disorders. (See "Juvenile idiopathic

arthritis: Epidemiology and immunopathogenesis", section on 'Gamma-delta-T cells'.)

!

An interferon (IFN) alfa–induced gene expression signature in muscle and serum, which may be stimulated by

autoantibodies associated with nucleic acids, was seen in gene expression studies that used microarray-based

technologies [29,30]. This gene expression is similar to the gene expression signature seen in patients with

systemic lupus erythematosus (SLE).

!

There is an increased prevalence of Coxsackie B antibodies in children with JDM compared with matched control

[31].

!

Case reports of viral isolation from muscle specimens in adult myositis have been described [32].!

There is an association between echovirus infection and chronic PM in children with agammaglobulinemia [33].!

A seasonal variation of onset in JDM exists, with clustering of cases in the spring and summer [34].!

http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/34http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/33http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/32http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/31http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/29,30http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-idiopathic-arthritis-epidemiology-and-immunopathogenesis?source=see_link&sectionName=Gamma-delta-T+cells&anchor=H25#H25http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/28http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/26,27http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations?topicKey=ALLRG%2F6419&elapsedTimeMs=1&source=search_result&searchTerm=polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#H515392924http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/25http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations?topicKey=ALLRG%2F6419&elapsedTimeMs=1&source=search_result&searchTerm=polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#H9http://www.uptodate.com.pbidi.unam.mx:8080/contents/clinical-manifestations-of-dermatomyositis-and-polymyositis-in-adults?source=see_link&sectionName=Myositis-specific+autoantibodies&anchor=H17269508#H17269508http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/24http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/22http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/22,23http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/21http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/20http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/19http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/1


3/14



However, attempts at demonstrating a viral etiology of JDM have failed. As an example, a study of 79 patients with new

onset JDM found normal antibody titers to herpes simplex virus, coxsackievirus B 1 through 6, and Toxoplasma gondii

[37]. Another report using the polymerase chain reaction was unable to demonstrate evidence of viral genetic material

the muscle of 20 individuals with active, untreated, recent-onset JDM [38].

CLINICAL MANIFESTATIONS — Muscle weakness is the hallmark of JDM and JPM, although approximately 5 percenof patients with JDM do not have clinically evident weakness (amyopathic JDM) [4]. In addition, patients with JDM, but

not JPM, present with characteristic rashes (picture 1). Children with JDM and JPM also may have constitutional

symptoms (fever, weight loss, fatigue, and headache), which may be the initial finding prior to the onset of muscle

weakness and, in patients with JDM, rash.

The clinical presentation of JDM varies and is exemplified by the two following case series. In the first review from a

single tertiary Canadian center of 105 patients with JDM (mean age at diagnosis 7.6 years), the most common

symptoms/findings and their frequency noted at disease onset were [4]:

The second case series is from the JDM Research Registry and included 166 newly diagnosed children living in the

continental United States from 1994 to 1999 [10]. The mean age of diagnosis was 7.5±3.8 years, and the median

duration of symptoms prior to diagnosis was four months. There was no difference in the age of diagnosis or duration o

untreated disease based upon gender or ethnicity. The initial symptoms/findings on presentation were:

Thus, although nearly all patients with JDM develop muscle weakness, the classic rashes are the more common initial

finding on presentation. The severity of the weakness increased with the duration of symptoms prior to diagnosis.

Additional findings included:

The cutaneous manifestations of JDM may appear in the absence of clinically apparent muscle disease in a small

Respiratory and gastrointestinal complaints and/or antibiotic use are common in the three months before diagnos

of JDM [35,36].

!

Gottron's rash – 91 percent!

Heliotrope rash – 83 percent!

Malar/facial rash – 42 percent!

Nailfold capillary change – 80 percent!

Myalgia/arthralgia – 25 percent!

Dysphonia or dysphagia – 24 percent!

Anorexia – 18 percent!

Fever – 16 percent!

Rashes – 65 percent!

Weakness alone – 29 percent!

Both rash and weakness – 6 percent!

Lower height and weight compared with normative data from the National Health and Nutrition Examination Study

(NHANES) III survey

!

Nailfold capillary dilation!

Arthritis!

Difficulty swallowing!

Abdominal pain!

Fever !

http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/35,36http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/10http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/4http://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F52062&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/4http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/38http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/37


4/14



number of children. This presentation is termed amyopathic (or hypomyopathic) JDM. All such children require

evaluation by an experienced pediatric rheumatologist or neurologist to assure that they are not, in fact, weak. Children

with this presentation may never develop muscle weakness. However, in others, amyopathic JDM may reflect an early

phase in the disease course before muscle weakness has developed.

There are less data available on the clinical manifestations of JPM since it is a rare disease. In one series of 39 patient

diagnosed with JPM, the most common clinical features included [39]:

Patients with periungual capillary changes, Raynaud phenomenon, and gastrointestinal manifestations most likely have

overlap syndrome (JPM with features of scleroderma).

Muscle weakness — The inflammatory myopathies are characterized by symmetric, proximal muscle weakness. This

may present with functional limitations, such as difficulty getting up from the floor, getting into and out of motor vehicles

or climbing stairs. Washing or grooming hair may pose a challenge, and severely affected children may not be able to

feed themselves. In very young children, frequent falls may be an important symptom. A Gower's sign (pushing with the

hands on the legs, from the knees to hips, to attain an upright position) is frequently present.

Weakness of the palate and cricopharyngeal muscle may result in problems swallowing, a nasal voice, tracheal

aspiration, and reflux of food into the nasopharynx. Involvement of the upper esophagus can lead to dysphagia for solid

and liquids [40].

Testing of muscle strength is reviewed separately. (See "Juvenile dermatomyositis and polymyositis: Diagnosis", sectio

on 'Muscle strength testing'.)

Cutaneous manifestations — Cutaneous manifestations are common in children with JDM and include a characterist

heliotrope rash, Gottron’s papules, nailfold capillary changes, and skin ulcerations (picture 2). The rashes may occur

simultaneously with muscle involvement or appear prior to obvious muscular weakness. Rash is an important

distinguishing feature between JDM and JPM as it is not present in the latter condition. Skin disease may be

exacerbated by exposure to sunlight [41]. Calcinosis, a well-recognized complication, is discussed in detail separately.

(See "Juvenile dermatomyositis and polymyositis: Treatment, complications, and prognosis", section on 'Calcinosis'.)

Heliotrope rash — Heliotrope dermatitis is a reddish-purple rash on the upper eyelids, often accompanied by

swelling of the eyelid (picture 1). Malar and facial erythema may also be present. Heliotrope rash is one of the most

Proximal muscle weakness – 100 percent!

Fatigue – 82 percent!

Arthritis or arthralgias – 69 percent!

Myalgias – 64 percent!

Falling – 60 percent!

Weight loss – 54 percent!

Fever – 47 percent!

Muscle atrophy – 46 percent!

Distal muscle weakness – 44 percent!

Dysphagia – 41 percent!

Abdominal pain – 31 percent!

Periungual capillary changes – 31 percent!

Raynaud phenomenon – 28 percent!

Dysphonia – 24 percent!

Palpitations – 23 percent!

http://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F52062&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-treatment-complications-and-prognosis?source=see_link&sectionName=Calcinosis&anchor=H20#H20http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/41http://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F63190&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-diagnosis?source=see_link&sectionName=Muscle+strength+testing&anchor=H6#H6http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/40http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/39


5/14



common findings in patients with JDM, with a reported rate of 83 percent in the previously mentioned Canadian study

and a 94 percent rate in 44 patients from Hungary [4,42]. Periorbital edema, upper lid edema, or telangiectasia of the

eyelid capillaries can be seen in 50 to 90 percent of children [43,44].

Gottron's papules — Gottron's papules are an erythematous, papulosquamous eruption over the dorsal surfaces o

the knuckles (picture 1). The term "Gottron's sign" is often used if the lesions are not papular. Similar lesions can occur

over the extensor aspects of the elbows, knees, and medial malleoli, at times mimicking psoriasis. Gottron's papules ar

a common feature in patients with JDM, with a reported rate of 91 percent of Canadian and 77 percent of Hungarian

patients from the previously mentioned studies [4,42].

Nailfold capillary changes — Nailfold capillary changes, including capillary dilatation, tortuosity, and dropout (loss

of capillary loops), as shown in panel C (picture 2), are a frequent sign and are probably present in all patients at early

stages of the disease [45]. The changes may be seen grossly but usually are only apparent under magnification. Nailfo

capillaroscopy is reviewed in detail separately. (See "Juvenile dermatomyositis and polymyositis: Diagnosis", section on

'Nailfold capillaroscopy'.)

Skin ulcerations — Ulcerative skin disease, as shown in panel E (picture 2), is a serious and potentially life-

threatening manifestation of JDM. Ulcers presumably reflect significant vasculopathy in the skin (with tissue hypoxia an

necrosis) and may signal vasculopathy in other organs (especially the lungs and gut). Patients with ulcerative lesions

have more severe disease and a worse prognosis. (See "Juvenile dermatomyositis and polymyositis: Treatment,complications, and prognosis", section on 'Prognosis'.)

Arthritis — Nonerosive arthralgia and arthritis may be present at the time of diagnosis or during the disease course

[3,4,46]. Contractures are sometimes seen but are usually related to muscle inflammation rather than arthritis.

Lipodystrophy — Acquired lipodystrophy, as shown in panel F (picture 2), and associated metabolic abnormalities suc

as insulin resistance, acanthosis nigricans, and type 2 diabetes are increasingly recognized in patients with JDM [47]:

Pulmonary involvement — Pulmonary manifestations are much less common in children with JDM or JPM than adults

but interstitial lung disease may occur [39,51]. High serum levels of Krebs von den Lungen-6 (KL-6), anti-melanoma

differentiation-associated gene 5 (MDA5) antibodies, and interleukin 18 (IL-18) are associated with rapidly progressiveinterstitial lung disease [52]. (See 'Immunologic mechanisms' above.)

Gastrointestinal vasculopathy — Gastrointestinal tract involvement is relatively rare in patients with JDM and in

patients with JPM and scleroderma features (overlap syndrome) but can be life threatening. Affected patients may

present with abdominal pain, pneumatosis intestinalis, gastrointestinal bleeding, or perforation [2,53]. Acute

gastrointestinal vasculitis and chronic abdominal endarteropathy have been described in patients with JDM, indicating

that the underlying pathology leading to ulceration and perforation of the intestines is complex [54]. (See "Juvenile

dermatomyositis and polymyositis: Treatment, complications, and prognosis", section on 'Intestinal perforation'.)

In a study of 20 patients with JDM, four were found to have lipodystrophy accompanied by either insulin resistanc

or type 2 diabetes, while an additional eight had glucose and lipid abnormalities without evidence of lipodystrophy

[48].

!

In another study of 20 patients, 13 patients had lipoatrophy based upon subcutaneous fat quantification by skinfol

caliper, including eight patients with physical findings of lipodystrophy [49]. Oral glucose tests were normal in all

patients, but 12 of 18 patients tested were found to have hypertriglyceridemia.

!

In a retrospective review, JDM alone or in association with another autoimmune disease (eg, juvenile idiopathic

arthritis) was the underlying disease in 18 of 23 children with acquired lipodystrophy. Other findings included

acanthosis nigricans (n = 5 patients), hyperpigmentation (n = 5), elevated liver enzymes (n = 5), and hypertension

(n =3) [50].

!

http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/50http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/49http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/48http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-treatment-complications-and-prognosis?source=see_link&sectionName=Intestinal+perforation&anchor=H21#H21http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/54http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/2,53http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations?topicKey=ALLRG%2F6419&elapsedTimeMs=1&source=search_result&searchTerm=polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#H5http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/52http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/39,51http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/47http://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F63190&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/3,4,46http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-treatment-complications-and-prognosis?source=see_link&sectionName=PROGNOSIS&anchor=H23#H23http://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F63190&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-diagnosis?source=see_link&sectionName=Nailfold+capillaroscopy&anchor=H7#H7http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/45http://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F63190&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/4,42http://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F52062&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/43,44http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/4,42


6/14



Any patient with JDM experiencing abdominal pain that persists or progresses warrants careful investigation because

gastrointestinal vasculopathy may occur late in the disease course or in a patient with only mild myositis. Of note,

abdominal radiographs and stool testing for occult blood may be normal in patients with gastrointestinal involvement.

The need for further investigation, such as abdominal ultrasonography or computed tomography (CT), must be guided

by clinical suspicion for significant gastrointestinal involvement.

Anasarca — Anasarca is an uncommon finding seen in patient with JDM. The presence of anasarca at presentation is

potential poor prognostic sign indicating severe disease that may respond slowly to treatment and may not respond to

glucocorticoids alone. The generalized edema may be the result of a diffuse capillary leak resulting from vascular

endothelial damage [55].

LABORATORY FINDINGS — Elevated levels of serum muscle enzymes (creatine kinase, lactate dehydrogenase,

aldolase alanine aminotransferase, aspartate aminotransferase) indicate muscle damage and are often found in JDM o

JPM. (See "Juvenile dermatomyositis and polymyositis: Diagnosis", section on 'Measurement of muscle enzymes'.)

Although other blood tests are often performed in patients suspected of having childhood inflammatory myopathy, these

studies are often not directly useful in establishing the diagnosis. They include the following:

HISTOLOGY — Muscle biopsy specimens from patients with JDM often contain an inflammatory infiltrate. The

inflammatory cells are located perivascularly. These scattered inflammatory infiltrates are composed predominantly of

monocytes and T cells, but other cells types such as B cells, mast cells, and, rarely, eosinophils are also present [60].

Normal muscle cells do not express class I major histocompatibility complex (MHC) antigens, but these antigens are

strongly expressed on muscle fibers in patients with JDM [61]. MHC class I overexpression is an early event in JDM an

may occur in the absence of lymphocytic infiltration and muscle damage.

SUMMARY — Juvenile dermatomyositis (JDM) and juvenile polymyositis (JPM) are rare autoimmune myopathies

affecting children.

Complete blood count – Leukocytosis and anemia are uncommon findings at disease onset, with the possible

exception of a low hematocrit in a child with significant gastrointestinal bleeding. Lymphopenia may be present in

children with JDM and usually resolves after glucocorticoid therapy [56].

!

Inflammatory markers – Both C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) may be elevated

in patients with JDM and JPM [57]. However, these often do not correlate with the degree of inflammation detecte

clinically and are not useful in making the diagnosis or monitoring disease activity in patients with JDM or JPM.

!

von Willebrand factor (vWF) – Although several studies have shown that children with active JDM have increased

plasma vWF levels [58,59], increased vWF levels are not more specific for active disease than serum muscle

enzyme measurements. Blood vessel injury is thought to cause the release of vWF from platelets and endothelial

cells, resulting in elevated plasma levels of vWF.

!

Autoantibodies – Although antinuclear antibodies (ANAs) are present in 70 percent of patients with JDM and JPM

a positive ANA is nonspecific and has limited diagnostic value. Testing for myositis-specific antibodies is not

routinely performed, unless JPM is suspected, because the tests are expensive and not readily available. (See

'Immunologic mechanisms' above and "Juvenile dermatomyositis and polymyositis: Diagnosis", section on 'Our

approach'.)

!

JDM is the most common of these disorders, accounting for 85 percent of cases, with a reported incidence that

ranges from two to four cases per million children. (See 'Epidemiology' above.)

!

Although the etiology of JDM and JPM remains unclear, it is suspected that these disorders are caused by an!

http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations?topicKey=ALLRG%2F6419&elapsedTimeMs=1&source=search_result&searchTerm=polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#H2http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-diagnosis?source=see_link&sectionName=Our+approach&anchor=H515393324#H515393324http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations?topicKey=ALLRG%2F6419&elapsedTimeMs=1&source=search_result&searchTerm=polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#H5http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/58,59http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/57http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/56http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/61http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/60http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-diagnosis?source=see_link&sectionName=Measurement+of+muscle+enzymes&anchor=H8#H8http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/55


7/14



Use of UpToDate is subject to the Subscription and License Agreement.

REFERENCES

1. Arahata K, Engel AG. Monoclonal antibody analysis of mononuclear cells in myopathies. I: Quantitation of subseaccording to diagnosis and sites of accumulation and demonstration and counts of muscle fibers invaded by Tcells. Ann Neurol 1984; 16:193.

2. Banker BQ, Victor M. Dermatomyositis (systemic angiopathy) of childhood. Medicine (Baltimore) 1966; 45:261.

3. McCann LJ, Juggins AD, Maillard SM, et al. The Juvenile Dermatomyositis National Registry and Repository (UKand Ireland)--clinical characteristics of children recruited within the first 5 yr. Rheumatology (Oxford) 2006;45:1255.

4. Ramanan AV, Feldman BM. Clinical features and outcomes of juvenile dermatomyositis and other childhood onsemyositis syndromes. Rheum Dis Clin North Am 2002; 28:833.

5. Oddis CV, Conte CG, Steen VD, Medsger TA Jr. Incidence of polymyositis-dermatomyositis: a 20-year study of

hospital diagnosed cases in Allegheny County, PA 1963-1982. J Rheumatol 1990; 17:1329.6. Pelkonen PM, Jalanko HJ, Lantto RK, et al. Incidence of systemic connective tissue diseases in children: a

nationwide prospective study in Finland. J Rheumatol 1994; 21:2143.

7. Symmons DP, Sills JA, Davis SM. The incidence of juvenile dermatomyositis: results from a nation-wide study. BJ Rheumatol 1995; 34:732.

8. Mendez EP, Lipton R, Ramsey-Goldman R, et al. US incidence of juvenile dermatomyositis, 1995-1998: resultsfrom the National Institute of Arthritis and Musculoskeletal and Skin Diseases Registry. Arthritis Rheum 2003;49:300.

9. Gardner-Medwin JM, Dolezalova P, Cummins C, Southwood TR. Incidence of Henoch-Schönlein purpura,Kawasaki disease, and rare vasculitides in children of different ethnic origins. Lancet 2002; 360:1197.

10. Pachman LM, Abbott K, Sinacore JM, et al. Duration of illness is an important variable for untreated children with

juvenile dermatomyositis. J Pediatr 2006; 148:247.

11. Orione MA, Silva CA, Sallum AM, et al. Risk factors for juvenile dermatomyositis: exposure to tobacco and air pollutants during pregnancy. Arthritis Care Res (Hoboken) 2014; 66:1571.

12. Harati Y, Niakan E, Bergman EW. Childhood dermatomyositis in monozygotic twins. Neurology 1986; 36:721.

13. LEONHARDT T. Familial occurrence of collagen diseases. II. Progressive systemic sclerosis and dermatomyositi Acta Med Scand 1961; 169:735.

14. Miller FW, Chen W, O'Hanlon TP, et al. Genome-wide association study identifies HLA 8.1 ancestral haplotypealleles as major genetic risk factors for myositis phenotypes. Genes Immun 2015; 16:470.

autoimmune reaction within the small blood vessels and/or the muscle tissue of genetically susceptible individuals

possibly in response to infection or environmental triggers. (See 'Pathogenesis' above.)

Symmetrical proximal muscle weakness is the hallmark clinical feature of these two disorders. In addition,

heliotrope rash (reddish-purple rash on the upper eyelids, often accompanied by swelling of the eyelid) (picture 1)

and Gottron's papules (erythematous, papulosquamous eruption over the dorsal surfaces of the knuckles) (picture

1) are characteristic rashes of JDM. Children with JDM and JPM may also have constitutional symptoms (fever,

weight loss, fatigue, and headache), which may appear prior to the onset of muscle weakness and rash (in patien

with JDM).

!

Other clinical manifestations of JDM include nailfold capillary changes, skin ulcerations, calcinosis (soft tissue

calcification), nonerosive arthralgia and arthritis, lipodystrophy, and insulin resistance (picture 2). Gastrointestinal

vasculopathy is a relative rare but life-threatening manifestation that may present as abdominal pain, pneumatosi

intestinalis, gastrointestinal bleeding, or perforation. (See 'Clinical manifestations' above.)

!

http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations?topicKey=ALLRG%2F6419&elapsedTimeMs=1&source=search_result&searchTerm=polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#H8http://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F63190&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F52062&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/image?imageKey=PEDS%2F52062&topicKey=ALLRG%2F6419&rank=1%7E150&source=see_linkhttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations?topicKey=ALLRG%2F6419&elapsedTimeMs=1&source=search_result&searchTerm=polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#H3http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/14http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/13http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/12http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/11http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/10http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/9http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/8http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/7http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/6http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/5http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/4http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/3http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/2http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/1http://www.uptodate.com.pbidi.unam.mx:8080/contents/license


8/14


9/14



37. Pachman LM, Hayford JR, Hochberg MC, et al. New-onset juvenile dermatomyositis: comparisons with a healthycohort and children with juvenile rheumatoid arthritis. Arthritis Rheum 1997; 40:1526.

38. Pachman LM, Litt DL, Rowley AH, et al. Lack of detection of enteroviral RNA or bacterial DNA in magneticresonance imaging-directed muscle biopsies from twenty children with active untreated juvenile dermatomyositis Arthritis Rheum 1995; 38:1513.

39. Mamyrova G, Katz JD, Jones RV, et al. Clinical and laboratory features distinguishing juvenile polymyositis andmuscular dystrophy. Arthritis Care Res (Hoboken) 2013; 65:1969.

40. McCann LJ, Garay SM, Ryan MM, et al. Oropharyngeal dysphagia in juvenile dermatomyositis (JDM): anevaluation of videofluoroscopy swallow study (VFSS) changes in relation to clinical symptoms and objectivemuscle scores. Rheumatology (Oxford) 2007; 46:1363.

41. Dugan EM, Huber AM, Miller FW, et al. Photoessay of the cutaneous manifestations of the idiopathic inflammatormyopathies. Dermatol Online J 2009; 15:1.

42. Constantin T, Ponyi A, Orbán I, et al. National registry of patients with juvenile idiopathic inflammatory myopathiein Hungary--clinical characteristics and disease course of 44 patients with juvenile dermatomyositis. Autoimmunit2006; 39:223.

43. Akikusa JD, Tennankore DK, Levin AV, Feldman BM. Eye findings in patients with juvenile dermatomyositis. JRheumatol 2005; 32:1986.

44. COOK CD, ROSEN FS, BANKER BQ. DERMATOMYOSITIS AND FOCAL SCLERODERMA. Pediatr Clin North

Am 1963; 10:979.45. Schmeling H, Stephens S, Goia C, et al. Nailfold capillary density is importantly associated over time with muscle

and skin disease activity in juvenile dermatomyositis. Rheumatology (Oxford) 2011; 50:885.

46. Tse S, Lubelsky S, Gordon M, et al. The arthritis of inflammatory childhood myositis syndromes. J Rheumatol2001; 28:192.

47. Bingham A, Mamyrova G, Rother KI, et al. Predictors of acquired lipodystrophy in juvenile-onset dermatomyositisand a gradient of severity. Medicine (Baltimore) 2008; 87:70.

48. Huemer C, Kitson H, Malleson PN, et al. Lipodystrophy in patients with juvenile dermatomyositis--evaluation of clinical and metabolic abnormalities. J Rheumatol 2001; 28:610.

49. Verma S, Singh S, Bhalla AK, Khullar M. Study of subcutaneous fat in children with juvenile dermatomyositis. Arthritis Rheum 2006; 55:564.

50. Pope E, Janson A, Khambalia A, Feldman B. Childhood acquired lipodystrophy: a retrospective study. J Am AcadDermatol 2006; 55:947.

51. Kobayashi I, Yamada M, Takahashi Y, et al. Interstitial lung disease associated with juvenile dermatomyositis:clinical features and efficacy of cyclosporin A. Rheumatology (Oxford) 2003; 42:371.

52. Kobayashi N, Takezaki S, Kobayashi I, et al. Clinical and laboratory features of fatal rapidly progressive interstitialung disease associated with juvenile dermatomyositis. Rheumatology (Oxford) 2015; 54:784.

53. Downey EC Jr, Woolley MM, Hanson V. Required surgical therapy in the pediatric patient with dermatomyositis. Arch Surg 1988; 123:1117.

54. Mamyrova G, Kleiner DE, James-Newton L, et al. Late-onset gastrointestinal pain in juvenile dermatomyositis as manifestation of ischemic ulceration from chronic endarteropathy. Arthritis Rheum 2007; 57:881.

55. Mitchell JP, Dennis GJ, Rider LG. Juvenile dermatomyositis presenting with anasarca: A possible indicator of severe disease activity. J Pediatr 2001; 138:942.

56. Brown VE, Pilkington CA, Feldman BM, et al. An international consensus survey of the diagnostic criteria for juvenile dermatomyositis (JDM). Rheumatology (Oxford) 2006; 45:990.

57. Haas RH, Dyck RF, Dubowitz V, Pepys MB. C-reactive protein in childhood dermatomyositis. Ann Rheum Dis1982; 41:483.

58. Guzmán J, Petty RE, Malleson PN. Monitoring disease activity in juvenile dermatomyositis: the role of vonWillebrand factor and muscle enzymes. J Rheumatol 1994; 21:739.

59. Bloom BJ, Tucker LB, Miller LC, Schaller JG. von Willebrand factor in juvenile dermatomyositis. J Rheumatol

http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/59http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/58http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/57http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/56http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/55http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/54http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/53http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/52http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/51http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/50http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/49http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/48http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/47http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/46http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/45http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/44http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/43http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/42http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/41http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/40http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/39http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/38http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/37


10/14


Página 10 ttp://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-derm…polimiositis&selectedTitle=1%7E150&view=print&displayedView=full#

1995; 22:320.

60. Wedderburn LR, Varsani H, Li CK, et al. International consensus on a proposed score system for muscle biopsyevaluation in patients with juvenile dermatomyositis: a tool for potential use in clinical trials. Arthritis Rheum 200757:1192.

61. Li CK, Varsani H, Holton JL, et al. MHC Class I overexpression on muscles in early juvenile dermatomyositis. JRheumatol 2004; 31:605.

Topic 6419 Version 15.0

http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/61http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/60http://www.uptodate.com.pbidi.unam.mx:8080/contents/juvenile-dermatomyositis-and-polymyositis-epidemiology-pathogenesis-and-clinical-manifestations/abstract/59


11/14



GRAPHICS

Clinical images of typical juvenile dermatomyositis

(A) Heliotrope discoloration of the eyelids and malar or facial erythema.

(B) Scaly, red rash on the knuckles with Gottron's papules (erythematous,

papulosquamous eruption over the dorsal surfaces of the knuckles).

Reproduced with permission from: Feldman BM, Rider LG, Reed AM, Pachman LM. Juvenile

dermatomyositis and other idiopathic inflammatory myopathies of childhood. Lancet 2008;

371:2201. Illustration used with permission of Elsevier Inc. All rights reserved. Copyright

©2008 Elsevier Inc.

Graphic 52062 Version 5.0


12/14



Features of juvenile dermatomyositis

(A) Perivascular and perifascicular inflammatory infiltrates with necrotic

fibres, perifascicular atrophy, and regeneration in a muscle biopsy.

(B) Magnetic resonance imaging (MRI) is a sensitive indicator of

myositis. Inflamed areas appear bright on short-tau inversion recovery-

weighted images (arrows).

(C) Capillaries are most often abnormal when viewed at the nailfold.

Typical changes of dilatation with adjacent drop out (arrow) is seen.

(D) Approximately 30% of JDM patients have dystrophic calcinosis.

(E) Cutaneous ulceration with central necrosis, crust, and surrounding

erythema at the elbow of a 10-year-old boy with severe JDM.

(F) Lipoatrophy of the forearm (arrow) in a boy with JDM.

JDM: juvenile dermatomyositis.

Reproduced with permission from: Feldman BM, Rider LG, Reed AM, Pachman

LM. Juvenile dermatomyositis and other idiopathic inflammatory myopathies


14/14



Contributor Disclosures

Clare Hutchinson, MDCM, FRCPC Nothing to disclose. Brian M Feldman, MD, MSc, FRCPC Nothing to disclose.Thomas JA Lehman, MD Speaker's Bureau: Novartis [JIA (Canakinumab)]; Abbvie [JIA (Adalimumab)]; Amgen [JIA(Etanercept)]. Consultant/Advisory Boards: Novartis [JIA (Canakinumab)]; Abbvie [JIA (Adalimumab)]; Amgen [JIA(Etanercept)]; Genzyme [MPS I (Enzyme replacement therapy)]. Marc C Patterson, MD, FRACPGrant/Research/Clinical Trial Support: Vtesse [Niemann-Pick C (Cyclodextrin)]. Consultant/Advisory Boards: Actelion[Niemann-Pick C (Miglustat)]; Agios [CGD]; Amicus [Fabry, Gaucher, Pompe [(Migalastat)]; Novartis [MS]; Shire [MLD];

Vtesse [Niemann-Pick C]. Other Financial Interest: Sage [Honorarium as Editor-in-Chief of Journal of Child Neurologyand Child Neurology Open]. Elizabeth TePas, MD, MS Nothing to disclose.

Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed byvetting through a multi-level review process, and through requirements for references to be provided to support thecontent. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence.

Conflict of interest policy
http://www.uptodate.com.pbidi.unam.mx:8080/home/conflict-interest-policy

Juvenile Dermatomyositis and Polymyositis: Epidemiology, Pathogenesis, And Clinical Manifestations

Documents

Transcript of Juvenile Dermatomyositis and Polymyositis: Epidemiology, Pathogenesis, And Clinical Manifestations