Anemia, splenomegaly, and increased osmotic fragility of erythrocytes in Abyssinian and Somali cats.
OBJECTIVE
To determine clinical and clinicopathologic features of a chronic intermittent severe hemolytic anemia characterized by erythrocyte osmotic fragility in Abyssinian and Somali cats.


METHODS
Case series.


METHODS
13 Abyssinian and 5 Somali cats.


METHODS
History, pedigree information, and results of routine laboratory tests, special erythrocyte studies, and histologic evaluation of splenic and hepatic specimens were analyzed.


RESULTS
Age at which clinical signs of anemia were first apparent ranged from 6 months to 5 years. Ten cats had splenomegaly. Most often, the PCV was between 15 and 25%, but it was as low as 5% at some times. The anemia was characterized by macrocytosis and mild to moderate reticulocytosis, but no poikilocytosis. Hyperglobulinemia, lymphocytosis, mild hyperbilirubinemia, and high hepatic enzyme activities were common findings. Results of Coombs tests and tests for infectious diseases were negative. The erythrocytic osmotic fragility was high in affected cats (mean osmotic fragility, 0.66 to 0.78%), compared with healthy cats (0.48 to 0.58). No specific membrane protein abnormality, erythrocyte enzyme deficiency, or hemoglobinopathy was identified. Histologic evaluation of splenic and hepatic specimens revealed extramedullary hematopoiesis and hemosiderosis. Four of the 5 Somali cats were closely related.


CONCLUSIONS
On the basis of results of pedigree analyses, the apparent breed predilection, and the exclusion of other known causes of anemia in cats, we believe that the hemolytic anemia in these cats was likely a result of a novel hereditary erythrocyte defect. A genetic predisposition to immune-mediated destruction of erythrocytes could not be ruled out.
Kohn
B
B
Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104, USA.
Goldschmidt
M H
MH
Hohenhaus
A E
AE
Giger
U
U
D000744:Anemia, Hemolytic, Autoimmune / Q000235:genetics / Q000473:pathology / Q000662:veterinary*; D000818:Animals; D001774:Blood Chemical Analysis; D002371:Cat Diseases / Q000235:genetics / Q000473:pathology*; D002415:Cats; D002851:Chromatography, High Pressure Liquid / Q000662:veterinary; D003298:Coombs Test / Q000662:veterinary; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D005260:Female; D006400:Hematocrit / Q000662:veterinary; D006454:Hemoglobins / Q000032:analysis; D006651:Histocytochemistry; D008099:Liver / Q000473:pathology; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D008854:Microscopy, Electron / Q000662:veterinary; D009996:Osmotic Fragility; D010375:Pedigree; D011770:Pyruvate Kinase / Q000032:analysis; D013154:Spleen / Q000473:pathology; D013163:Splenomegaly / Q000235:genetics / Q000473:pathology / Q000662:veterinary*
D006454:Hemoglobins; D008565:Membrane Proteins; D011770:Pyruvate Kinase