Acquired growth hormone deficiency and its evolution with the application of growth hormone in an adult Golden Retriever

Abstract

Growth hormone (GH) deficiency is an endocrinopathy of low prevalence and even less frequent, in the
adult dog (acquired). The case of a 7-year-old neutered female Golden retriever breed is reported. The
reason for consultation is severe hair loss. The remaining hair was dry and discolored. Also, this bitch
presented atrophy of the temporal muscles and the owner reported a state of apathy.
At the time of the consultation, she was being treated with levothyroxine 600 µg every 12h for a period of
6 months without results and despite the fact that the concentrations of TSH and total T4 were within the
reference range. The thyroid axis hormones were reassessed and the adrenal axis hormones (ACTH,
cortisol, and cortisol: creatinine ratio in urine) were also requested; all within the reference range. Likewise,
an ultrasound of the thyroid gland and the adrenal glands was requested, their morphologies and sizes being
normal. Before these results, it was decided to evaluate the somatotrophic axis by measuring IGF-1,
stimulation with xylazine and computed tomography of the sellar region (hypophysis). IGF-1 concentration
was <15 ng/mL (200-400 ng/mL) and there was no response to xylazine stimulation, which is indicative of
GH deficiency. The tomography revealed the presence of an adenoma measuring 5.25 x 4.86 mm (P/B=1.1).
Treatment with growth hormone was indicated and at 2 months hair growth, improvement in cognitive
attitude, and an increase in IGF-1 concentrations to 95.4 ng/mL were already noticeable.
CONCLUSION: This case exemplifies the importance of a comprehensive diagnostic approach,
considering less common diagnoses, and the necessity of specialized veterinary care to effectively address
complex health issues in animals. The success of the growth hormone deficiency treatment in this case
underscores the significance of accurately identifying the underlying cause of the symptoms, leading to a
significant improvement in the quality of life of the canine patient.