OCULAR MANIFESTATIONS OF SYSTEMIC DISEASE

IN DOGS

Dr. Christa Corbett, DVM, MS, DACVOSeptember 17, 2016

Outline Cardiovascular Hematologic Neurologic Dermatologic Internal medicine

Infectious diseaseEndocrine

Oncologic

CARDIOVASCULAR

Systemic hypertension Pathogenesis:

Ischemic necrosis of vessel walls = increased vascular permeability

Patient variation is important to remember, but a sustained systolic BP >180 mmHg will lead to end organ damage

Systemic hypertension Ophthalmic signs:

Retinal vascular tortuosity (occasionally) Hemorrhages

○ Retinal is most common○ Subconjunctival○ Iris stroma○ Hyphema

Retinal edema or detachment Treatment is targeted at the underlying disease

HEMATOLOGIC

Anemia Does not commonly

lead to ocular disease (~10%)

Ophthalmic signs:Conjunctival pallorFocal retinal hemorrhages

○ Due to tissue hypoxia of the vascular walls

Thrombocytopenia Commonly causes ocular disease

25% have mild ocular signs (focal hemorrhages)16% have severe ocular signs (hyphema)

Ophthalmic signs:Hemorrhages:

○ Retinal is most common○ Subconjunctival○ Iris stroma○ Hyphema

Treatment is targeted at the underlying disease

Hypertriglyceridemia/Hyperlipidemia Primary (familial)

Miniature schnauzer, Beagle, Briard, Collie, and SheltieAnecdotally in the Capital District Miniature Pinschers

Secondary (secondary to other systemic disease)Hypothyroidism, Diabetes, Pancreatitis most commonCushings, renal or hepatic diseases also rarely possible

Hypertriglyceridemia/Hyperlipidemia Ophthalmic signs:

Lipemia retinalisLipemic aqueousCorneal lipid

Hypertriglyceridemia/Hyperlipidemia Ophthalmic signs:

Lipemic aqueous○ Must have alteration in blood-aqueous barrier

(uveitis, intraocular surgical patients)○ Chicken or egg Uveitis started and lipids

leak, or intravascular lipemia causes vascular endotheliitis and increased permeability

Lipid plaques just about anywhere!

Hypertriglyceridemia/Hyperlipidemia Treatment:

Treat underlying diseaseThorough diet history

○ (ask the same questions 3-5 times sometimes!!!)

Hypertriglyceridemia/Hyperlipidemia

STRICT low fat diet○ Royal Canin Gastrointestinal Low Fat

Study by Xenoulis et al JVIM 2011Less than 25g of total fat per 1000 kcal

○ Nutritionist for a low nutritionally balanced fat home cooked diet (U of Tenn)

○ Fruits and Vegetables for treatsLipid binding agents

○ All off-label (as of 2014)○ Omega-3 fatty acids, Fibrates (Gemfibrozil),

Niacin

Hyperviscosity Causes:

Multiple myeloma, lymphoma, CLL, ehrlichiosis

Ocular findings:Dilated, tortuous retinal vesselsPerivascular edema or infiltrateRetinal hemorrhages (along small arterioles)

Treatment is targeted at the underlying cause

NEUROLOGIC

Granulomatous Meningoencephalitis Suspect immune-mediated inflammation of the

meninges and/or brain Optic nerve (+/- retinal) involvement =

blindness, mydriasis Ophthalmic findings:

BlindnessMydriasisPapilledemaPeripapillary hemorrhagesRarely retinal infiltrate or detachment

Granulomatous Meningoencephalitis Diagnosis:

Neurologic work-up including MRI and CSF Treatment:

Systemic immunosuppression○ Steroids AND Cystosine arabinoside,

Azthioprine, Leflunomide or Cyclosporine

DERMATOLOGIC

Autoimmune dermatitides Pemphigus complex diseases Discoid lupus erythematosus Systemic lupus erythematosus

All can lead to facial dermatitis characterized by erosions, ulcers, crusting, scaling and depigmentation

Parasitic dermatitides Demodex

Ophthalmic findings:○ Alopecia, scaly skin around eyes, lips and

forelegs○ Rarely pruritic unless secondary bacterial

involvement Sarcoptes

Rarely periocular

Uveodermatologic Syndrome Aka Vogt-Koyanagi-Harada or VKH-

like syndromeHuman version also linked to hearing

loss and meningitis Immune-mediated destruction

of melanocytes Akita is the top breed, but has

been reported in dozens ofothers

Uveodermatologic Syndrome Ophthalmic findings:

Anterior uveitisChorioretinitis with varying severity

○ Focal regions of subretinal exudate○ Retinal detachments

Loss of choroidal pigment Dermatologic findings:

Vitiligo (skin depigentation) and poliosis (hair depigmentation)

○ Often restricted to face○ Can be ulcerative in nature

Uveodermatologic Syndrome Diagnosis:

Biopsy of tissue○ Enucleation if glaucomatous and blind○ Dermal biopsy of facial mucocutaneous

junctions

Uveodermatologic Syndrome Treatment:

Systemic immunosuppressionSteroids AND Azthioprine, Mycophenolate or

CyclosporineTopical anti-inflammatories for anterior

uveitisPrednisolone acetate AND Diclofenac in most

cases+/- Glaucoma medications

June 26, 2009

September 15, 2009

June 26, 2009

September 15, 2009

INTERNAL MEDICINE – Infectious disease

Tick-Borne disease Lyme

3% incidence of ocular disease in 132 seropositive dogs

Ophthalmic findings:○ Conjunctivitis○ Corneal edema○ Anterior uveitis○ Retinal petechia○ Chorioretinitis○ Retinal detachment○ Orbital disease

Tick-Borne disease Anaplasma

A. platys = Canine Cyclic Thrombocytopenia○ Ophthalmic findings:

See findings associated with Thrombocytopenia

Tick-Borne disease Ehrlichia

Ocular lesions can occur in any stage of disease, mostly with E. canis

10-37% of cases have ocular signsOphthalmic findings:

○ Thrombocytopenia findings○ Vasculitis lesions

Anterior or posterior uveitis

Tick-Borne disease RMSF

81% of cases have ocular signsOphthalmic findings:

○ Thrombocytopenia findings○ Vasculitis lesions

Anterior or posterior uveitis

Parasitic disease Toxoplasma

Rarely causes ocular disease in dogs Ophthalmomyiasis

Fly larvae penetrate into the eye○ Conjunctival extension○ Penetrating trauma?

May see actual larvae, or can see chronic tracts

Parasitic disease Ophthalmomyiasis

Subclassifications:○ Externa = Orbital and extraocular ○ Interna anterior = larvae in anterior chamber○ Interna posterior = larvae in posterior segment

Treatment:○ Manual removal if possible○ Organophosphate treatment is controversial,

as dead larvae can incite more inflammation

Fungal disease Aspergillus

Local disease (nasal mucosa and respiratory) unlikely to cause ocular disease

Disseminated disease can lead to panuveitis, chorioretinitis and retinal detachment

CoccidiomycosisSouthwestern USPanuveitis with disseminated diseaseOften unilateral

Fungal disease Cryptococcus

Not very common in dogsGranulomatous to

pyogranulomatous chorioretinitis with or without exudative retinal detachment

Optic neuritis possible

Fungal disease Histoplasma

Chorioretinitis most common, possibly extension to anterior uvea

Optic neuritis

Fungal disease Blastomycosis

Ocular involvement in 48% of casesOphthalmic findings:

○ Often begins posterior, so early ocular stages aren’t often notedHematologic spread to the fine capillaries of the choroidMild = focal subretinal granulomaSevere = exudative retinal detachment

○ Anterior uveitis is often due to endophthalmitis, organisms are

often not found in anterior uvea

Fungal disease Blastomycosis

Diagnosis:○ Urine blasto antigen (MiraVista)○ Cytology or biopsy of tissue

Subretinal or vitreous aspirate, enucleation, or biopsy of another distant lesion

○ Serology:AGID test

- 67% sensitivity- 100% specificity

Fungal disease Blastomycosis

Treatment:○ Long-term azole antifungals (itraconazole has

80% clinical cure rate)Recurrence is common, can be years later

○ +/- oral steroidsNot reported to worsen survival, and may help ocular

disease○ Topical anti-inflammatories ○ +/- Glaucoma meds

Enucleation???○ Often recommended for blind, painful eyes○ NO proof that the eye can sequester

organisms, so enucleation is considered palliative for pain control, but not essential for survival

INTERNAL MEDICINE – Endocrine

Diabetes Ophthalmic findings:

CataractCorneal endothelial cell lossRetinal vascular damage and hemorrhage

○ Note: NOT the same as the proliferative diabetic retinopathy in humans

Decreased corneal sensitivityLow schirmer tear test

Hypothyroidism Ocular symptoms not directly caused by

hypothyroidism, but associated conditions:KCS

○ Multi-glandular immune-mediated inflammation?Hyperlipidemia can lead to corneal lipid

degeneration, lipemic aqueous or lipemia retinalisNeurologic signs

○ Horner’s, Facial paralysis

ONCOLOGIC

Lymphoma Most common metastatic intraocular

tumor 37% of lymphoma cases present with

ocular diseaseAnterior uveitis – 49%Posterior uveitis – 9%Panuveitis – 14%Retinal hemorrhage – 23%Adnexal disease – 6%

Lymphoma Most common metastatic intraocular tumor 37% of lymphoma cases present with ocular

diseaseAnterior uveitis – 49%Posterior uveitis – 9%Panuveitis – 14%Retinal hemorrhage – 23%Adnexal disease – 6%

Ocular involvement makes this Stage 5, so shorter survival

Other metastatic disease Mostly carcinomas and sarcomas Malignant melanoma (i.e. ungual) Transmissible venereal tumor Ophthalmic findings:

HyphemaUveitisGlaucoma

Questions???