A rare case of congenital hypothyroidism in a juvenile cat - case report

Abstract

ABSTRACT A 9-month-old female domestic shorthair cat was presented to a veterinary hospital with an unusual combination of clinical signs, including apathy, dwarfism, and hypothermia. Physical examination revealed notable findings such as hypotension, tachypnea, matted fur, and retained deciduous teeth. A complete blood count revealed lymphopenia and toxic neutrophils and activated platelets, while the biochemical profile indicated decreased levels of urea, alkaline phosphatase, and phosphorus, all below the reference intervals. The FIV/FeLV rapid test was positive for FeLV. Radiographic examination showed open physes; abdominal ultrasound revealed microhepathia, and a suspected portosystemic shunt. Electrocardiography demonstrated left axis deviation, prolonged QRS complex duration, and bifascicular block. Hormonal testing revealed a Total T4 concentration markedly below the reference interval and an elevated TSH level. Levothyroxine sodium therapy was initiated, and a follow-up hormonal test one month later showed values within the normal range.