Prevalence of hypersomatotropism and hyperthyroidism in cats with diabetes mellitus from referral centers in Buenos Aires (2020-2022).

OBJECTIVES: The aim of this study was to estimate the prevalence of hypersomatotropism (HST) and hyperthyroidism in cats with diabetes mellitus (DM) from referral centers in Buenos Aires, Argentina. METHODS: This was a prospective study. Systematic screening of serum insulin-like growth factor 1 (IGF-1) and total thyroxine was performed in all cats diagnosed with DM at referral centers in Buenos Aires between February 2020 and February 2022. RESULTS: In total, 154 diabetic cats were evaluated (99 males and 55 females; median age 12 years [range 3-21]; mean body weight 5 kg [range 2-12]). Altogether, there were 115 (75%) domestic shorthairs and one domestic longhair; the remaining 38 cats were purebred (mainly Siamese, n = 25 [16%]). Twenty (12.9%) cats had IGF-1 concentrations >1000 ng/ml, and three (1.9%) had IGF-1 concentrations between 800 and 1000 ng/ml along with pituitary enlargement on CT, resulting in a 14.9% HST prevalence rate in diabetic cats. Intracranial imaging was performed in all cats with HST; median pituitary dorsoventral height was 5.8 mm (range 3.1-9.5). Fourteen of 23 (61%) cats had phenotypic changes consistent with acromegaly at the time of diagnosis of HST. Four of 154 (2.5%) cats had concurrent hyperthyroidism. CONCLUSIONS AND RELEVANCE: To date, this is the first study outside of Europe to have evaluated the prevalence of HST and hyperthyroidism in cats with DM. In Buenos Aires referral centers, feline HST is the most common concurrent endocrinopathy in cats with DM but with a lower prevalence than has previously been reported. Hyperthyroidism is a rare concurrent endocrinopathy in diabetic cats from referral centers in Buenos Aires.

Gynaecomastia in a male neutered cat with an adrenal tumour and associated hyperprogesteronism, hypercortisolism and hyperaldosteronism.

CASE SUMMARY: A 7-year-old male neutered domestic longhair cat was presented with chronic progressive gynaecomastia, polydipsia, polyphagia, weight loss and poor fur regrowth. Sexualised behavioural changes were not reported and virilisation was not present on physical examination. Pertinent haematology, biochemistry and urinalysis findings at the time of referral included mild hypokalaemia. Left adrenomegaly and mild prostatomegaly were identified on a CT scan. Evaluation of adrenal hormones with a low-dose dexamethasone suppression test, serum progesterone, testosterone, oestradiol, plasma aldosterone, renin, plasma metanephrine and normetanephrine measurement supported a diagnosis of hyperprogesteronism, hyperaldosteronism and hypercortisolism. Adrenalectomy was performed and histopathology was consistent with an adrenocortical tumour. Clinical signs and hormone elevations resolved postoperatively. RELEVANCE AND NOVEL INFORMATION: To our knowledge, this is the second report of gynaecomastia secondary to an adrenal tumour in a male neutered cat and the first associated with hyperprogesteronism.

Retrospective study of aldosterone and progesterone secreting adrenal tumors in 10 cats.

BACKGROUND: Primary hyperaldosteronism caused by adrenal neoplasia has been well described in cats. Multiple corticosteroid abnormalities occur in a subset of affected cats, but characterizations of this syndrome are limited to several case reports. OBJECTIVES: To describe a series of cats with adrenal tumors secreting aldosterone and additional corticosteroids. ANIMALS: Ten cats with multiple corticosteroid secreting adrenocortical tumors. METHODS: Retrospective case series. Medical records of cats with adrenal tumors secreting both aldosterone and progesterone were identified. Data concerning historical findings, clinicopathologic features, treatments, and outcomes were retrieved from medical records. RESULTS: All 10 cats had diabetes mellitus in addition to biochemical features of hyperaldosteronism such as hypokalemia. High corticosterone concentrations were observed in all 3 cats in which this corticosteroid was measured. Ultrasound examinations revealed unilateral adrenal tumors in all 10 cases, and the contralateral adrenal gland was either atrophied or not identified in 5 cats. Three of 4 cats developed hypoadrenocorticism after surgical adrenalectomy. Three cats achieved diabetic remission after adrenalectomy. Two cats treated with adrenalectomy survived >1 year, 1 cat survived 6.5 months, and 1 cat was alive 5.5 months after diagnosis. Survival >1 year occurred in 2 of 4 cats treated with medical management alone. Two cats were not treated. CONCLUSIONS AND CLINICAL IMPORTANCE: The presence of multiple corticosteroid abnormalities should be considered in cats with aldosterone secreting adrenal tumors, especially those with concurrent diabetes mellitus. Both surgical and medical management can result in long-term survival, although diabetic remission was documented only in cats undergoing adrenalectomy.