Epstein-Barr associated acute cerebellar ataxia in an adult · Epstein-Barr associated acute...

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Epstein-Barr associated acute cerebellar ataxia in an adult Adam N Hofer, MD, MPH; Joan Addington-White, MD University of Wisconsin-Hospitals & Clinics Introduction Case Description Acute cerebellar ataxia (ACA) is a rare, o3en self6limi8ng, inflammatory disease that can be triggered by both infec8ous and non6infec8ous processes. ACA is one of several known central nervous system (CNS) complica8ons of an Ebstein6Barr viral (EBV) infec8on. Here, we present a case of ACA as the primary manifesta8on of a primary EBV infec8on without the classical features of infec8ous mononucleosis. A 706year6old ac8ve and generally healthy woman presented to her primary care physician with a 26week history of progressive gait disturbance. Her symptoms began following the onset of a self6limi8ng diarrheal illness while traveling to New York City. Her unsteadiness worsened to the point that she had several falls and required assistance for ambula8on. She had no other localizing infec8ous symptoms and denied changes in mental status. She had a history of hypertension and osteoporosis. There had been no recent medica8on changes. She had no family history of ataxia or other neurological disorders. On examina8on, she was afebrile (36.3° C) and hemodynamically stable. Cardiopulmonary and abdominal examina8ons were normal. There was no cervical lymphadenopathy or tonsillar exudates. She had no dysarthria or nystagmus. She had a wide6based, unsteady gait and was unable to walk without assistance. She also had mild dysdiadochokinesia on finger6 to6nose tes8ng. Romberg test was nega8ve. Complete blood count was notable for a leukocytosis (11.5 K/uL), lymphocytosis (6580/uL), and mild thrombocytosis (430 K/uL). A blood smear demonstrated reac8ve lymphocytes. A basic metabolic panel was normal. C6reac8ve protein was mildly elevated (2 mg/dL); ESR was normal. B12 and TSH were normal. An MRI of the brain was notable for ventriculomegaly, le3 greater than right; of note, there was no cerebellar enhancement. Due to concern for an atypical presenta8on of normal pressure hydrocephalus (NPH), she underwent lumbar puncture (LP) with cerebrospinal fluid (CSF) removal. She did not have significant improvement in her ataxia following lumbar puncture per physical therapy. CSF analysis subsequently revealed only two nucleated cells, elevated protein at 59 mg/dl (15645), and posi8ve EBV qualita8ve PCR (Table 1). As such, serum EBV serology was ordered and notable for posi8ve EBV viral capsid an8gen (VCA) IgM confirming acute EBV infec8on (Table 2). Given lack of significant improvement in ataxia with CSF removal and posi8ve EBV serology, it was felt that her presenta8on was most consistent with EBV6associated ACA. Her ataxia improved gradually with non6pharmacologic therapy and had completely resolved within ten weeks at 8me of outpa8ent follow6up. Discussion We report a case of acute cerebellar ataxia (ACA) as the primary manifesta8on of acute Epstein6Barr virus (EBV) infec8on in a 706year6old female. In retrospect, the pa8ent in our case reported mild fa8gue and a sore throat at the onset of her symptoms. However, while rare, ACA can present without the systemic manifesta8ons of infec8ous mononucleosis (IM) such as fever, pharyngi8s, lymphadenopathy, and fa8gue. 1 ACA is one of several known neurological complica8ons of EBV (Table 3), which can be seen in up to 7.3 percent of pa8ents with EBV. 2 ACA is rare (incidence 1 in 1006500k) and most commonly affects children. In adults, ACA has a male predominance and typically affects pa8ents less than 30 years of age. 3,4 However, as in our case, ACA has been documented in pa8ents in their 70s. 5 The pathogenesis is incompletely understood, however, two mechanisms have been speculated: (1) a delayed post6infec8ous autoimmune process, (2) direct viral infec8on of the cerebellum. 1,2,5 The detec8on of viral DNA in CSF in our case would support the laher. The differen8al diagnosis for ACA in an adult is broad, and includes infec8ous, neoplas8c, paraneoplas8c, inflammatory, and toxic e8ologies (Table 4). 1 In this case, acute EBV infec8on was concluded to be the causa8ve agent based on posi8ve EBV viral capsid an8gen IgM in the serum. Repeat EBV serology approximately 10 weeks a3er diagnosis was notable for nega8ve EBV VCA IgM and posi8ve EBV VCA IgG, consistent with resolving acute infec8on (Table 2). MRI is the most commonly performed imaging modality in pa8ents with acute ataxia and may demonstrate bilateral or unilateral diffuse cerebellar abnormali8es (Figure 2); however, brain MRI is unrevealing in the majority of pa8ents with ACA and abnormal imaging lacks both specificity and prognos8c value. 6,7 Our pa8ent was noted to have ventriculomegaly, thus ini8ally raising concern for normal pressure hydrocephalus (NPH). However, hydrocephalus has been reported in up to 42 percent of pa8ents in one case series. 6 ACA secondary to EBV infec8on is usually a benign, self6limi8ng inflammatory condi8on that can most o3en be treated with suppor8ve therapy. Complete recovery is most o3en seen within 3613 weeks. 8 However, obstruc8ve hydrocephalus and chronic cerebellar atrophy have been reported. 6 Treatment has commonly included cor8costeroids and/or an86viral though there is currently insufficient evidence to support the use of either in the treatment of ACA. 2,9 Our pa8ent was treated with suppor8ve therapy and made a complete recovery a3er approximately ten weeks. References 1. McCarthy CL, McColgan P, Mar8n P. Acute cerebellar ataxia due to Epstein6Barr virus. Pract Neurol. 2012 Aug;12(4):238640. doi: 10.1136/practneurol620116000115. No abstract available. Erratum in: Pract Neurol. 2012 Dec;12(6):399. 2. Ali K, Lawthom C. Epstein6Barr virus6associated cerebellar ataxia. BMJ Case Rep. 2013 Apr 22;2013. doi:pii: bcr2013009171. 10.1136/bcr620136009171. 3. Davis DP, Marino A. Acute cerebellar ataxia in a toddler: case report and literature review. J Emerg Med. 2003 Apr;24(3):28164. Review. 4. Klockgether T, Döller G, Wüllner U, Petersen D, Dichgans J. Cerebellar encephali8s in adults. J Neurol. 1993 Jan;240(1):17620. 5. Fujimoto H, Asaoka K, Imaizumi T, Ayabe M, Shoji H, Kaji M. Epstein6Barr virus infec8ons of the central nervous system. Intern Med. 2003 Jan;42(1):33640. 6. De Bruecker Y, Claus F, Demaerel P, Ballaux F, Sciot R, Lagae L, Buyse G, Wilms G. MRI findings in acute cerebelli8s. Eur Radiol. 2004 Aug;14(8):1478683. Epub 2004 Feb 13. Review. 7. Park KM, Kim SE, Kim SE. An elderly case of acute cerebelli8s a3er alleged vaccina8on. J Mov Disord. 2012 May;5(1):2163. doi: 10.14802/jmd.12006. Epub 2012 May 30. 8. Erzurum S, Kalavsky SM, Watanakunakorn C. Acute cerebellar ataxia and hearing loss as ini8al symptoms of infec8ous mononucleosis. Arch Neurol. 1983 Nov;40(12): 76062. 9. Van Lierde A, Righini A, Tremola8 E. Acute cerebelli8s with tonsillar hernia8on and hydrocephalus in Epstein6Barr virus infec8on. Eur J Pediatr. 2004 Nov;163(11): 689691. Epub 2004 Aug 12. Conclusions Acute Cerebellar Ataxia (ACA) is a rare, usually self6limi8ng inflammatory syndrome characterized by cerebellar dysfunc8on (e.g., gait disturbance, dysmetria) EBV may cause ACA in adults and ataxia may be the sole manifesta8on of a primary EBV infec8on Conven8onal MRI is o3en normal during an acute infec8on though may demonstrate cerebellar swelling or hydrocephalus Treatment is suppor8ve; there is currently insufficient evidence to support the rou8ne use of cor8costeroids or an86viral medica8ons Figure 1: Axial T16weighted sec8on MRI image showing ventriculomegaly in our pa8ent A P Table 2: EBV Serology Day 0 Day 77 EBV VCA IgM + - EBV VCA IgG - + EBV EA IgG - - EBNA - - VCA, viral capsid antigen; EA, early antigen; EBNA, EBV nuclear antigen Table 4: Causes of Acute Cerebellar Ataxia Vascular Infarction, hemorrhage, Vasculitis Inflammatory MS, Acute disseminated encephalomyelitis Toxic Alcohol, Drugs Neoplastic Posterior fossa space occupying lesions Paraneoplastic Anti-Yo, Anti-Hu, Anti-Ri, anti-Tr, anti- VGCC, anti-Ma, Anti-Ta/M2, anti- CRMPS/CV2, anti-mGluRi Infectious EBV, VZV, mumps, Mycoplasma pneumonia, Japanese encephalitis virus, Legionella, Coxsackie virus, HIV, poliovirus Genetic Episodic ataxia 1 and 2 MS, Mutliple sclerosis, EBV, Epstein-Barr Virus; VZV, varicella zoster virus (Source: McCarthy et al, 2012) Table 1: Results of LP & CSF analysis Opening pressure 18 cm H2O Closing pressure 9 cm H2O Removed CSF volume 28 mL Protein 59 mg/dL (15-45) Glucose 52 mg/dL (40-80) Nucleated Cells 2 /uL CSF Culture Negative EBV PCR Positive Enterovirus PCR Negative HSV PCR Negative Paraneoplastic Autoantibodies Negative EBV, Ebstein-barr Virus; HSV, Herpes-simplex virus Figure 2: Axial T26weighted image showing increased signal intensity in bilateral cerebellar hemispheres and vermis. 6 (Source: D Bruecker et al, 2004) 2 Table 3: Neurological Complications of EBV Meningitis Encephalitis Mononeuritis Guillain-Barre Syndrome Ophthalmoplegia Optic neuritis Acute demyelinating encephalomyelitis (ADEM) Acute Cerebellar Ataxia (Source: Ali & Lawthom, 2013) P

Transcript of Epstein-Barr associated acute cerebellar ataxia in an adult · Epstein-Barr associated acute...

Page 1: Epstein-Barr associated acute cerebellar ataxia in an adult · Epstein-Barr associated acute cerebellar ataxia in an adult Adam N Hofer, MD, MPH; Joan Addington-White, MD University

Epstein-Barr associated acute cerebellar ataxia in an adult

Adam N Hofer, MD, MPH; Joan Addington-White, MD University of Wisconsin-Hospitals & Clinics

Introduction

Case Description

Acute&cerebellar&ataxia&(ACA)&is&a&rare,&o3en&self6limi8ng,&inflammatory&disease&that&can&be&triggered&by&both&infec8ous&and&non6infec8ous&processes.&ACA&is&one&of&several&known&central&nervous&system&(CNS)&complica8ons&of&an&Ebstein6Barr&viral&(EBV)&infec8on.&Here,&we&present&a&case&of&ACA&as&the&primary&manifesta8on&of&a&primary&EBV&infec8on&without&the&classical&features&of&infec8ous&mononucleosis.&&

A&706year6old&ac8ve&and&generally&healthy&woman&presented&to&her&primary&care&physician&with&a&26week&history&of&progressive&gait&disturbance.&Her&symptoms&began&following&the&onset&of&a&self6limi8ng&diarrheal&illness&while&traveling&to&New&York&City.&Her&unsteadiness&worsened&to&the&point&that&she&had&several&falls&and&required&assistance&for&ambula8on.&She&had&no&other&localizing&infec8ous&symptoms&and&denied&changes&in&mental&status.&She&had&a&history&of&hypertension&and&osteoporosis.&There&had&been&no&recent&medica8on&changes.&She&had&no&family&history&of&ataxia&or&other&neurological&disorders.&&&&On&examina8on,&she&was&afebrile&(36.3°&C)&and&hemodynamically&stable.&Cardiopulmonary&and&abdominal&examina8ons&were&normal.&There&was&no&cervical&lymphadenopathy&or&tonsillar&exudates.&She&had&no&dysarthria&or&nystagmus.&She&had&a&wide6based,&unsteady&gait&and&was&unable&to&walk&without&assistance.&She&also&had&mild&dysdiadochokinesia&on&finger6to6nose&tes8ng.&Romberg&test&was&nega8ve.&&&&Complete&blood&count&was&notable&for&a&leukocytosis&(11.5&K/uL),&lymphocytosis&(6580/uL),&and&mild&thrombocytosis&(430&K/uL).&A&blood&smear&demonstrated&reac8ve&lymphocytes.&A&basic&metabolic&panel&was&normal.&C6reac8ve&protein&was&mildly&elevated&(2&mg/dL);&ESR&was&normal.&B12&and&TSH&were&normal.&An&MRI&of&the&brain&was&notable&for&ventriculomegaly,&le3&greater&than&right;&of&note,&there&was&no&cerebellar&enhancement.&Due&to&concern&for&an&atypical&presenta8on&of&normal&pressure&hydrocephalus&(NPH),&she&underwent&lumbar&puncture&(LP)&with&cerebrospinal&fluid&(CSF)&removal.&She&did&not&have&significant&improvement&in&her&ataxia&following&lumbar&puncture&per&physical&therapy.&CSF&analysis&subsequently&revealed&only&two&nucleated&cells,&elevated&protein&at&59&mg/dl&(15645),&and&posi8ve&EBV&qualita8ve&PCR&(Table&1).&As&such,&serum&EBV&serology&was&ordered&and&notable&for&posi8ve&EBV&viral&capsid&an8gen&(VCA)&IgM&confirming&acute&EBV&infec8on&(Table&2).&Given&lack&of&significant&improvement&in&ataxia&with&CSF&removal&and&posi8ve&EBV&serology,&it&was&felt&that&her&presenta8on&was&most&consistent&with&EBV6associated&ACA.&&&Her&ataxia&improved&gradually&with&non6pharmacologic&therapy&and&had&completely&resolved&within&ten&weeks&at&8me&of&outpa8ent&follow6up.&&&

Discussion

We&report&a&case&of&acute&cerebellar&ataxia&(ACA)&as&the&primary&manifesta8on&of&acute&Epstein6Barr&virus&(EBV)&infec8on&in&a&706year6old&female.&In&retrospect,&the&pa8ent&in&our&case&reported&mild&fa8gue&and&a&sore&throat&at&the&onset&of&her&symptoms.&However,&while&rare,&ACA&can&present&without&the&systemic&manifesta8ons&of&infec8ous&mononucleosis&(IM)&such&as&fever,&pharyngi8s,&lymphadenopathy,&and&fa8gue.1&ACA&is&one&of&several&known&neurological&complica8ons&of&EBV&(Table&3),&which&can&be&seen&in&up&to&7.3&percent&of&pa8ents&with&EBV.2&&&&ACA&is&rare&(incidence&1&in&1006500k)&and&most&commonly&affects&children.&In&adults,&ACA&has&a&male&predominance&and&typically&affects&pa8ents&less&than&30&years&of&age.3,4&However,&as&in&our&case,&ACA&has&been&documented&in&pa8ents&in&their&70s.5&The&pathogenesis&is&incompletely&understood,&however,&two&mechanisms&have&been&speculated:&(1)&a&delayed&post6infec8ous&autoimmune&process,&(2)&direct&viral&infec8on&of&the&cerebellum.1,2,5&&The&detec8on&of&viral&DNA&in&CSF&in&our&case&would&support&the&laher.&&&The&differen8al&diagnosis&for&ACA&in&an&adult&is&broad,&and&includes&infec8ous,&neoplas8c,&paraneoplas8c,&inflammatory,&and&toxic&e8ologies&(Table&4).1&In&this&case,&acute&EBV&infec8on&was&concluded&to&be&the&causa8ve&agent&based&on&posi8ve&EBV&viral&capsid&an8gen&IgM&in&the&serum.&Repeat&EBV&serology&approximately&10&weeks&a3er&diagnosis&was&notable&for&nega8ve&EBV&VCA&IgM&and&posi8ve&EBV&VCA&IgG,&consistent&with&resolving&acute&infec8on&(Table&2).&&&&MRI&is&the&most&commonly&performed&imaging&modality&in&pa8ents&with&acute&ataxia&and&may&demonstrate&bilateral&or&unilateral&diffuse&cerebellar&abnormali8es&(Figure&2);&however,&brain&MRI&is&unrevealing&in&the&majority&of&pa8ents&with&ACA&and&abnormal&imaging&lacks&both&specificity&and&prognos8c&value.6,7&Our&pa8ent&was&noted&to&have&ventriculomegaly,&thus&ini8ally&raising&concern&for&normal&pressure&hydrocephalus&(NPH).&However,&hydrocephalus&has&been&reported&in&up&to&42&percent&of&pa8ents&in&one&case&series.6&&&&ACA&secondary&to&EBV&infec8on&is&usually&a&benign,&self6limi8ng&inflammatory&condi8on&that&can&most&o3en&be&treated&with&suppor8ve&therapy.&Complete&recovery&is&most&o3en&seen&within&3613&weeks.8&However,&obstruc8ve&hydrocephalus&and&chronic&cerebellar&atrophy&have&been&reported.6&&Treatment&has&commonly&included&cor8costeroids&and/or&an86viral&though&there&is&currently&insufficient&evidence&to&support&the&use&of&either&in&the&treatment&of&ACA.2,9&Our&pa8ent&was&treated&with&suppor8ve&therapy&and&made&a&complete&recovery&a3er&approximately&ten&weeks.&&

References 1.  McCarthy&CL,&McColgan&P,&Mar8n&P.&Acute&cerebellar&ataxia&due&to&Epstein6Barr&virus.&Pract&Neurol.&2012&Aug;12(4):238640.&doi:&10.1136/practneurol620116000115.&No&

abstract&available.&Erratum&in:&Pract&Neurol.&2012&Dec;12(6):399.&&2.  Ali&K,&Lawthom&C.&Epstein6Barr&virus6associated&cerebellar&ataxia.&BMJ&Case&Rep.&2013&Apr&22;2013.&doi:pii:&bcr2013009171.&10.1136/bcr620136009171.&&3.  Davis&DP,&Marino&A.&Acute&cerebellar&ataxia&in&a&toddler:&case&report&and&literature&review.&J&Emerg&Med.&2003&Apr;24(3):28164.&Review.&&4.  Klockgether&T,&Döller&G,&Wüllner&U,&Petersen&D,&Dichgans&J.&Cerebellar&encephali8s&in&adults.&J&Neurol.&1993&Jan;240(1):17620.&&5.  Fujimoto&H,&Asaoka&K,&Imaizumi&T,&Ayabe&M,&Shoji&H,&Kaji&M.&Epstein6Barr&virus&infec8ons&of&the&central&nervous&system.&Intern&Med.&2003&Jan;42(1):33640.&&6.  De&Bruecker&Y,&Claus&F,&Demaerel&P,&Ballaux&F,&Sciot&R,&Lagae&L,&Buyse&G,&Wilms&G.&MRI&findings&in&acute&cerebelli8s.&Eur&Radiol.&2004&Aug;14(8):1478683.&Epub&2004&Feb&

13.&Review.&&7.  Park&KM,&Kim&SE,&Kim&SE.&An&elderly&case&of&acute&cerebelli8s&a3er&alleged&vaccina8on.&J&Mov&Disord.&2012&May;5(1):2163.&doi:&10.14802/jmd.12006.&Epub&2012&May&30.&&8.  Erzurum&S,&Kalavsky&SM,&Watanakunakorn&C.&Acute&cerebellar&ataxia&and&hearing&loss&as&ini8al&symptoms&of&infec8ous&mononucleosis.&Arch&Neurol.&1983&Nov;40(12):

76062.&&9.  Van&Lierde&A,&Righini&A,&Tremola8&E.&Acute&cerebelli8s&with&tonsillar&hernia8on&and&hydrocephalus&in&Epstein6Barr&virus&infec8on.&Eur&J&Pediatr.&2004&Nov;163(11):

689691.&Epub&2004&Aug&12.&&

Conclusions

•  Acute&Cerebellar&Ataxia&(ACA)&is&a&rare,&usually&self6limi8ng&inflammatory&syndrome&characterized&by&cerebellar&dysfunc8on&(e.g.,&gait&disturbance,&dysmetria)&

•  EBV&may&cause&ACA&in&adults&and&ataxia&may&be&the&sole&manifesta8on&of&a&primary&EBV&infec8on&

•  Conven8onal&MRI&is&o3en&normal&during&an&acute&infec8on&though&may&demonstrate&cerebellar&swelling&or&hydrocephalus&

•  Treatment&is&suppor8ve;&there&is&currently&insufficient&evidence&to&support&the&rou8ne&use&of&cor8costeroids&or&an86viral&medica8ons&&&

Figure&1:&Axial&T16weighted&sec8on&MRI&image&showing&ventriculomegaly&in&our&pa8ent&

A&

P&

Table 2: EBV Serology Day 0 Day 77

EBV VCA IgM + - EBV VCA IgG - + EBV EA IgG - - EBNA - - VCA, viral capsid antigen; EA, early antigen; EBNA, EBV nuclear antigen

Table 4: Causes of Acute Cerebellar Ataxia Vascular Infarction, hemorrhage, Vasculitis

Inflammatory MS, Acute disseminated encephalomyelitis

Toxic Alcohol, Drugs Neoplastic Posterior fossa space occupying lesions

Paraneoplastic Anti-Yo, Anti-Hu, Anti-Ri, anti-Tr, anti-VGCC, anti-Ma, Anti-Ta/M2, anti-CRMPS/CV2, anti-mGluRi

Infectious

EBV, VZV, mumps, Mycoplasma pneumonia, Japanese encephalitis virus, Legionella, Coxsackie virus, HIV, poliovirus

Genetic Episodic ataxia 1 and 2 MS, Mutliple sclerosis, EBV, Epstein-Barr Virus; VZV, varicella zoster virus (Source: McCarthy et al, 2012)

Table 1: Results of LP & CSF analysis

Opening pressure 18 cm H2O Closing pressure 9 cm H2O Removed CSF volume 28 mL

Protein 59 mg/dL (15-45) Glucose 52 mg/dL (40-80) Nucleated Cells 2 /uL CSF Culture Negative EBV PCR Positive Enterovirus PCR Negative HSV PCR Negative Paraneoplastic Autoantibodies Negative EBV, Ebstein-barr Virus; HSV, Herpes-simplex virus

1479

Case 2

A 4-year-old girl was admitted to the hospital with a 3-week histo-ry of headache, fever and neck stiffness. Blood examinationshowed 6,750 leucocytes/mm3 and a CRP of 0.2 mg/dl. Serologi-cal tests were negative. CSF analysis revealed an elevated proteinconcentration (463 mg/l) and 15 leucocytes/mm3. A bronchus as-pirate was positive for influenza virus. Brain CT revealed a lesionin the left cerebellar hemisphere. MRI on day 7 showed abnormal-ities in both cerebellar hemispheres and in the vermis (Fig. 2),with a subtle pial contrast enhancement. The influenza virus(blood titer >1/128) was thought to have triggered the acute cere-bellitis. A follow-up MR examination performed 2 months latershowed residual changes in the left cerebellar hemisphere and aslight dilatation of the fourth ventricle.

Case 3

An 11-year-old girl was referred to the emergency departmentwith a 1-week history of progressive generalized weakness, fever,diarrhea and a productive cough. Cerebellar signs consist of a dys-arthric speech, dysmetria, an ataxic gait and horizontal nystagmus.CT was normal. Blood examination showed an elevated CRP(6.2 mg/dl). Serological tests were negative. Analysis of the CSFshowed an elevated protein content (566 mg/l) and 51 leuco-cytes/mm3. MRI, performed 6 days after admission, was normal,but 1 month later a slight dilatation of the fourth ventricle could beseen (Fig. 3). The patient was discharged 45 days after admissionwith persistent dysarthria and ataxia. Follow-up MRI, 1 year afterthe initial presentation, revealed widening of the folia and thefourth ventricle, indicating severe cerebellar atrophy (Fig. 3).

Case 4

A 26-year-old woman with severe headache and fever was re-ferred to the emergency department. She developed intermittent

diplopia, an ataxic gait and dysarthric speech. Blood examinationdisclosed 21,200 leucocytes/mm3 and a CRP of 6.2 mg/dl. CSFanalysis showed an increased protein concentration (800 mg/l) and138 leucocytes/mm3. Serological tests were negative. Brain CTwas normal. She was treated with antibiotics. One week after ad-mission, an acute neurological deterioration was observed and shebecame unconscious. Fundoscopy revealed bilateral papilledema.CRP had risen up to 13.5 mg/dl. Because of progressive swellingof the cerebellum and acute obstructive hydrocephalus, a ventricu-lostomy was performed. MRI revealed diffuse increased signal inboth cerebellar hemispheres (Fig. 4a) with a diffuse pial contrastenhancement (Fig. 4b). A posterior fossa decompression was nec-essary and a biopsy of the right cerebellar hemisphere and menin-ges was performed (Fig. 4c). Dura mater, arachnoidea and cerebel-lar parenchyma were infiltrated by a predominantly lymphocyticinflammatory infiltrate. MRI, 9 days after the posterior fossa de-compression, showed residual T2-signal alterations in both cere-bellar hemispheres and a normalization of the ventricles. Therewas a clinical improvement with only mild cerebellar signs 2months later.

Discussion

Acute cerebellitis (AC) is characterized by an acute orsubacute onset of cerebellar ataxia following an infectionor vaccination. Most common presenting symptoms in-clude truncal ataxia, dysmetria and headache. To ourknowledge, MR findings for 29 patients with acute cere-bellitis, in the absence of cerebral or brainstem lesions,have been reported in the literature. Table 1 illustratesthose 29 patients, including the four cases of thismanuscript [4–25]. The mean and median age at the timeof diagnosis of the 33 patients was, respectively, 13 and11 years (range 1–64 years). Varicella, measles, mumps

Fig. 1 Axial T2-weighted image at initial presentation shows in-creased signal intensity in the left cerebellar hemisphere

Fig. 2 Axial T2-weighted image at initial presentation showsmarked abnormal areas of increased signal intensity in both cere-bellar hemispheres and the vermis

Figure&2:&Axial&T26weighted&image&showing&increased&signal&intensity&in&bilateral&cerebellar&hemispheres&and&vermis.6&(Source:&D&Bruecker&et&al,&2004)&

1&

2&

Table 3: Neurological Complications of EBV Meningitis Encephalitis Mononeuritis Guillain-Barre Syndrome Ophthalmoplegia Optic neuritis Acute demyelinating encephalomyelitis (ADEM) Acute Cerebellar Ataxia (Source: Ali & Lawthom, 2013)

P&