Therapy of ocular and visceral leishmaniasis in a cat

Abstract

An 8-year-old, spayed female Domestic Short-haired cat was referred for further evaluation of chronic lymphocytic-plasmacytic stomatitis and bilateral ocular disease. The cat had been treated with systemic glucocorticoids for several months. Initial ophthalmic examination revealed bilateral deep stromal corneal ulcers, exudative panuveitis and secondary glaucoma. Mature mild neutrophilia and monocytosis were detected on complete blood cell count. Abnormalities in the serum profile were hyperglycemia, mild azotemia, hyperglobulinemia and moderate polyclonal gammapathy. Urinalysis revealed glucosuria without ketonuria. Diabetes mellitus was diagnosed and treatment with long-acting insulin was started. An enzyme-linked immunosorbent assay was highly positive for leishmaniasis, and treatment with allopurinol was started. Although specific topical treatment was applied, melting ulcers progressed to corneal perforation and both eyes were enucleated. Ocular histology showed large numbers of intracellular organisms compatible with amastigotes of the genus Leishmania located in the uveal tract, cornea, sclera and retina. Results of inmunohistochemistry staining on ocular samples were positive for Leishmania. Bone marrow cytology demonstrated numerous macrophages with intracytoplasmatic Leishmania. Polymerase chain reaction results on bone marrow for Leishmania were positive. Three weeks later, hypoglycemic episodes permitted withdrawal of the insulin therapy. To the authors' knowledge this is the first case of ocular and visceral leishmaniasis diagnosed in vivo and under systemic treatment in a cat.

Figure 1

Right eye. Note the mucoid discharge, chemosis and diffuse endothelial corneal edema. The stromal corneal ulceration is behind the nictitating membrane.

Figure 2

Histopathology of the right globe. Note the central corneal perforation, exudate in anterior chamber and vitreous. Hematoxlyn and eosin. Bar = 2000 µm.

Figure 3

Macrophagic cells containing numerous amastigote forms of Leishmania species in the uveal tract. Hematoxlyn and eosin. Bar = 20 µm.

Figure 4

Choroidal immunohistochemistry for detection of Leishmania amastigotes (brown staining) in the choroid. Bar = 800 µm.