REGIONAL CLINICAL CASE STUDIES OF FELINE HEARTWORM INFECTION. C.K. ROBERTSON 1*', A.R. DILLON 2, W.R. BRAWNER 2, J. GUERRERO 1.
1. MERCK AGVET, RAHWAY, NJ 07065; 2 AUBURN UNIVERSITY, AUBURN, AL 36849. Proceedings of 42nd AAVP, July 97, p109.
Diagnosis of feline heartworm disease can be elusive due to non-specific clinical signs, typically low worm burdens, unique pathophysiology in the cat and the limitations of currently available heartworm tests. Consequently, knowledge about this disease is still being acquired. The objective of this study was to survey the occurrence and clinical presentation of feline heartworm infection in specific regions of the United States among cats presenting with signs consistent with heartworm infection. Submission of 200 cases from fifteen private practices in Florida, South Carolina, Tennessee and Texas was targeted.
Cats entered in the study were at least 6 months of age and presented with one or more of the Lowing clinical signs: respiratory signs, including tachypnea, dyspnea or coughing; gastrointestinal signs, including a patted of intermittent vomiting unrelated to eating; or sudden death of uncertain etiology, particularly associated with respiratory distress prior to death. Data collected included: history and indoor/outdoor lifestyle; physical examination findings; thoracic radiography evaluations; Knott or DIFIL4 test results, DIROCHEK It antigen test results, antibody test results (Animal Diagnostics, Inc. and Heska Corporation laboratories); and CBC results.
Preliminary analysis of 134 cases provided the following results: 56/134 (42%) tested antibody positive on one or both antibody tests; 9/56 (16%) antibody positive cats were reported to be indoors I 00% of the time; and 15/56 (27%) antibody positive cats spent <IO% of their time outdoors. Four of the 134 were antigen positive. In 24 cases, thoracic radiographs showed signs consistent with heartworm infection.