Hipotireoidismo em cães dermatopatas: aspectos clínicolaboratoriais comparados ao exame histopatológico da pele

Abstract

This study was held at the Dermatology sector of the veterinarian clinic Animalia Rio de Janeiro RJ, from August 1998 to December 2005, 19,7% of the total amount of dogs treated at the clinic(4107) were guided to the Dermatology practice. A number of 266 (6.5%) animals were diagnosed with hypothyroidism. All 100% of the subjects had skin or coat disorders; moreover, 35.7% also had non cutaneous clinical signs of hypothyroidism. The most common dermatopathies were hair coat disorders (65.8%) and keratinization disorders (46.6%). The more repeated non cutaneous clinical signs in the study were metabolic disorders (19.6%) and reproductive (19.2%). The diagnosis of the disease was confirmed dosing the thyroid hormone and TSH (18%), biopsy and histopathology of the skin (35.3%) also by the association of both procedures (46.7%). Within these last group of animals , the histopathology was considered as the most efficient diagnosis method for hypothyroidism (97.6% / 98.2%) as for the Hormone tests the efficiency of this diagnosis was less expressive: T4 Free (72.7% / 75.8%) e T4 Total (77.8% / 73.9%). A percentage of 68,5% of the animals with hypothyroidism , had 1 or 2 secondary diseases or associated to the endocrinopathy, from which immune mediated disorders (45,9%) were accentuated . 157 of the diagnosed patients were submitted to treatment, with positive results in 93.6% of the cases. The disease was most found in females (57,9%). Dogs from 1 to 8 years old (81,6%) represented the age range of the affected animals. There were 43 breeds of dogs involved in the study, from which Chow Chow, Shar pei and English Cocker Spaniel were considered to have predisposition for the disease.