Two Great Danes were evaluated for signs of congestive heart failure. Dilated cardiomyopathy was diagnosed in each dog. Both dogs were diagnosed concurrently with primary hypothyroidism. Following appropriate supplementation with levothyroxine, both dogs showed significant improvement in myocardial contractility, as demonstrated by increased fractional shortening and reductions in left atrial size, and left ventricular end-systolic and diastolic diameters. These observations suggest that hypothyroidism may lead to myocardial failure in Great Danes that is partially or fully reversible following thyroid hormone replacement therapy, and that hypothyroidism should be considered in all Great Danes presenting with systolic failure.

Reports of cystic thyroid and parathyroid masses in cats are uncommon. Herein, the authors describe a series of four cats with cystic ventral cervical lesions, among them thyroid cyst (n=1), thyroid cystadenoma (n=2), and parathyroid adenocarcinoma (n=1). Presentations ranged from completely asymptomatic cervical swellings to signs related to local compression of adjacent structures (e.g., trachea). Ultrasonographic evaluation was helpful in localization of the mass in two cases. Hormone analysis and concentration of cystic fluid were performed in one cat. Surgical excision was performed successfully in three cases. Histopathological examination was performed in all four cases. Long-term prognosis was excellent for those cases in which follow-up was available.

Fourteen dogs with perianal fistulas were entered into a prospective clinical study to investigate the effects of long-term azathioprine on clinical outcome and to determine if the clinical results correlated with lymphocyte blastogenesis tests. Complete remission of perianal fistulas was seen in eight (57%) of 14 dogs; partial remission occurred in one (7%) dog; and no response was detected in five (36%) dogs. The results of lymphocyte blastogenesis assays did not correlate with therapeutic response.