Thyroid storm in a dog secondary to thyroid carcinoma

Abstract

Objective: To describe the clinical presentation, clinical course, and management of a dog with thyroid storm (TS) secondary to a functional thyroid carcinoma. Case summary: A 12-year-old neutered female Golden Retriever was evaluated for severe weight loss, hyperthermia, and tachycardia. The dog had a ventral neck mass and markedly increased thyroxine concentration. Cervical ultrasound showed a suspected left thyroid mass with invasion into the jugular vein. Despite aggressive therapy, the patient progressed to a clinical TS. Postmortem examination was supportive of the clinical diagnosis.

Long‐term survival in a dog with probable thyroid storm

“…There is no diagnostic test available for identification or confirmation to distinguish it from thyrotoxicosis. Multiple scoring systems exist for humans and, acknowledging the limitations of applying a human scoring system to a veterinary patient without validation, have been used when reporting suspected thyroid storm events in the previously mentioned case reports in one dog and one cat 4,6 . These studies used the Burch–Wartofsky Point Scale for Thyrotoxicosis 13 .…”

“…8 Clinical signs of thyrotoxicosis are similar in dogs, cats, and humans and include agitation, diarrhea, hyperthermia, tachycardia, tachypnea, tremors, and weight loss. 4,6,9,12 Thyroid storm is the most severe clinical manifestation of thyrotoxicosis. 1 However, this syndrome is poorly defined and only recently reported in veterinary medicine.…”

“…It can occur secondary to excess thyroid hormone production in the thyroid follicles, release of preformed hormone, or ingested thyroid hormone 8 . Clinical signs of thyrotoxicosis are similar in dogs, cats, and humans and include agitation, diarrhea, hyperthermia, tachycardia, tachypnea, tremors, and weight loss 4,6,9,12 …”

“…Thyroid storm is the most severe clinical manifestation of thyrotoxicosis 1 . However, this syndrome is poorly defined and only recently reported in veterinary medicine 4,6 . In humans, it is well‐described and associated with significant mortality in human emergency and intensive care units 10 .…”

“…Both methimazole and propylthiouracil (PTU) inhibit thyroid hormone production by inhibiting thyroid peroxidase. ‐Propylthiouracil is the most commonly used antithyroid medication in humans; however, adverse effects and limited studies prevent use in dogs 2,4,14 . Methimazole is routinely used to manage hyperthyroidism in cats and occasionally used in dogs 15 .…”