April 2018
S-F02 (NP)

Signalment (N27784F):  Unknown age and gender Doberman pinscher

HISTORY:  Presented with multiple non-pruritic, draining fluctuant nodules and fistulous tracts on the face, trunk and extremities along with exercise intolerance and ocular discharge.  The right eye had a grade 2/4 flare, rubeosis iridis and conjunctival injection.  The pupil would not dilate and the fundus could not be assessed.  The left eye had a detached retina.

HISTOPATHOLOGIC DESCRIPTION:  Eye:  Diffusely, the retina is separated from the retinal pigmented epithelium by a copious exudate composed of numerous viable and degenerate neutrophils, macrophages, rare multinucleated giant cells (foreign body type), myriad viable and degenerate yeast, many of which are within macrophages as well as extracellular and abundant eosinophilic homogenous to fibrillar and lacy material (fibrin and edema).  The yeast are 12-18 um diameter with a 2-3 um thick wall, a centrally located eosinophilic or basophilic granular nucleus and occasional broad base budding.  Diffusely, the overlying detached retina is convoluted and expanded by fibrin, edema and congestion.  Multifocally along the choroid, retinal pigmented epithelial cells are hypertrophic.  The choroid, ciliary body and iridial stroma are edematous, congested and are infiltrated by numerous plasma cells, macrophages and fewer neutrophils and lymphocytes.  The posterior and anterior chambers contain abundant fibrin.  Multifocally in the cornea there are numerous small blood vessels lined by plump endothelial cells (vascularization), separated by loosely arranged collagenous stroma with plump fibroblasts and rare lymphocytes, macrophages and neutrophils.


  1. Eye: Endophthalmitis, pyogranulomatous, diffuse, severe with retinal detachment and numerous budding yeasts, etiology consistent with Blastomyces dermatitidis, Doberman pinscher, canine.
  2. Eye, cornea: Keratitis, chronic-active, multifocal, mild with vascularization.

ETIOLOGIC DIAGNOSIS:  Mycotic ophthalmitis

CAUSE:  Blastomyces dermatitidis

CONDITION:  North American blastomycosis



Fungal conidia are inhaled > lung > hematogenous or lymphatic spread to various body systems (including the eye)



Pyogranulomatous or granulomatous endophthalmitis, granulomatous optic neuritis and exudative retinal separation




Mycotic ocular infections:



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  14. Zwick LS, Briggs MB, Tunev SS, Lichtensteiger CA, Murnane RD. Disseminated blastomycosis in two California sea lions (Zalophus californianus). J Zoo Wildl Med. 2000;31(2):211-214.


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