Chronic Idiopathic Neutropenia in a Cat

Abstract

Persistent neutropenia (0‐0.6 × I09 neutrophils/1) was documented during a 10‐month period in a 4‐year‐old spayed female domestic shorthair cat that was presented for anorexia and depression. Salient abnormalities detected on physical examination were fever (40.3oC), dehydration, and gingivitis. The cat was neutropenic (0.5 × 109 neutrophils/1) and an enzyme‐linked immunosorbent assay (ELISA) test for feline leukemia virus was negative. A bone marrow aspirate showed decreased numbers of mature granulocytic cells. In vitro bone marrow cultures for colony‐forming units‐granulocyte/macrophage (CFU‐GM) were performed comparing bone marrow from the patient with that of a normal cat. The patient had fewer CFU‐GM than the control. The number of CFU‐GM increased when bone marrow mononuclear cells were cultured in the presence of 10‐5 and 10‐6 mol/1 of hydrocortisone, but the cat did not respond to oral prednisolone therapy. The pathogenesis of the neutropenia in this cat remains obscure, but resembles the chronic idiopathic neutropenia syndrome of man. © 1988 American College of Veterinary Internal Medicine