Iatrogenic Primary Hypothyroidism Associated With Sulfamethoxazole-Trimethoprim Treatment of Nocardiosis in a Cat.

A 9-year-old mixed breed cat with a history of recurrent ulcerated skin lesions was diagnosed with nocardiosis. Three months after initiating potentiated sulfonamide treatment, the cat developed goitrous hypothyroidism, characterized by palpable enlargement of both thyroid lobes, low serum concentrations of total thyroxine (T4) and free thyroxine (fT4), and high serum thyroid-stimulating hormone (TSH) concentration. Thyroid scintigraphy identified symmetrical enlargement of both thyroid lobes, with increased radionuclide (Tc-pertechnetate) uptake.

Feline congenital hypothyroidism: a case report.

We report a two-month-old male cat weighing 630 grams with congenital hypothyroidism. The main complaints were difficulty defecating for more than three days and prostration. Physical examination revealed a broad, flat face, a short neck, enlarged submandibular lymph nodes, chemosis, mild bilateral mucopurulent ocular discharge, seborrheic coat, with gingival thickening around the upper and lower deciduous incisor teeth with partial eruption.