Diego Daniel Miceli

Case summary: A 12-year-old male neutered domestic shorthair cat was referred with severe polyphagia, polydipsia, polyuria, weight gain and signs of neurologic disease, including blindness, head tilt, and ataxia. Magnetic resonance imaging (MRI) identified a suprasellar mass consistent with a pituitary macroadenoma. Hypersomatotropism (HST) was diagnosed based on phenotypic changes compatible with acromegaly and an abnormally high serum insulin-like growth factor 1 (IGF-1) concentration (1253 ng/ml). Medical treatment with cabergoline monotherapy (10 μg/kg PO q24h) was prescribed. Progressive improvement of clinical signs was observed, accompanied by a gradual decrease in serum IGF-1 concentrations. Based on clinical and hormonal response, the dosing interval was sequentially extended to q48h and subsequently to q72h. By week 16 of treatment, signs of neurologic disease had resolved and serum IGF-1 concentrations decreased to values within the reference interval (749 ng/ml), while visual deficits persisted. By week 30, signs of neurologic disease remained absent, serum IGF-1 concentration was maintained within the reference interval, and diabetes mellitus did not develop. Cabergoline was well tolerated, with mild gastrointestinal signs reported early in the course of treatment. Relevance and novel information: This report describes a non-diabetic cat with HST secondary to a pituitary macroadenoma achieving sustained clinical and biochemical control with cabergoline monotherapy. This case demonstrates that a dopamine agonist might be an effective medical option in selected non-diabetic cats with HST, even in the presence of a large pituitary mass and signs of neurologic disease.

Case summary: A 19-year-old, spayed female domestic shorthair cat was referred with diabetes mellitus and difficulties in achieving glycemic control. Hypersomatotropism (HST) was diagnosed based on clinical signs compatible with acromegaly (prognathia inferior, broad facial features and abdominal enlargement), increased serum insulin-like growth factor 1 (IGF-1) concentration (4430 ng/ml) and pituitary enlargement (height 4.7 mm). Serum IGF-1 concentrations, biochemical analysis and urinalysis were performed at the time of HST diagnosis and after 10, 20, 30, 60, 120 and 180 days of pegvisomant treatment (PEGV, Somarvet; Pfizer). The cat received PEGV (1 mg/kg SC q24h) in combination with cabergoline (10 μg/kg PO q48h). Serum IGF-1 concentrations decreased abruptly to 396 ng/ml on day 10 of PEGV treatment and blood glucose concentrations also decreased rapidly. Insulin was no longer required after 7 days of PEGV. From day 30 (IGF-1 286 ng/ml), PEGV was administered q48h and the same therapeutic response was maintained after 60 days of treatment (IGF-1 290 ng/ml and diabetic remission). From day 120, PEGV was administered once weekly and normal IGF-1 concentrations (270 ng/ml) were observed after 180 days of treatment. The cat also showed improvements in echocardiographic variables and in her quality of life (QoL) score. Relevance and novel information: This is the first reported case of PEGV plus cabergoline treatment in a cat with HST. The results suggest that the combined treatment of PEGV and cabergoline was associated with normalization of IGF-1 concentrations, diabetic remission, and improvement of cardiovascular function and QoL over a short period.

Companion animal endocrinology has benefited from international standardisation of disease terminology for diabetes mellitus, Cushing’s syndrome, and hypoadrenocorticism through Project Agreeing Language in Veterinary Endocrinology (ALIVE). A group of 14 experts and one chair convened for the third cycle of Project ALIVE, focusing on thyroid disease terminology. The cycle employed the modified Delphi approach from previous cycles, augmented by procedural refinements—such as inclusion of an off-site chair and stricter adherence to timelines —to improve efficiency and flexibility. Novel in this round was the integration of feedback from a previous cycle, which resulted in updated definitions for diabetes mellitus originally developed in ALIVE Cycle 1. Outcomes: A 100% consensus was achieved among panellists and 91.4–100% among 105 members of international veterinary endocrinology societies (32% of total memberships) over 78 thyroid-related terminology items and five revised definitions pertaining to diabetes mellitus. These standardised definitions are expected to facilitate clearer communication and education, enhance diagnostic consistency, support research comparability, and improve clinical care in feline and canine endocrine diseases.

Objectives: The aim of this study was to describe the clinical, laboratory and thyroid imaging features of 17 adult cats with spontaneous hypothyroidism diagnosed over a 4-year period in four countries. Methods: This multicenter case series included cats diagnosed with spontaneous hypothyroidism between 2021 and 2025. We collected data on cats’ signalment, clinical signs, results of physical examination, routine laboratory and thyroid hormone testing, and thyroid imaging (scintigraphy, ultrasonography or CT). We also reviewed treatment data, including levothyroxine dosage, changes in serum thyroid hormone and creatinine concentrations, clinical progression and follow-up scintigraphy. Results: Cats were aged 2–14 years, with no breed predilection; 10 (58.8%) were male and seven (41.2%) female. Common clinical signs included lethargy, dermatologic signs (unkempt hair coat, increased shedding, dandruff, hair thinning), weight gain or obesity, and palpable goiter. The most common laboratory findings included azotemia (five cats), anemia (three cats) and worsening of pre-existing diabetes mellitus (two cats). A total of 13 (76.5%) cats had low serum thyroxine (T4), whereas all cats had high thyroid-stimulating hormone (TSH) concentrations. Thyroid imaging confirmed undetectable or atrophic thyroid tissue in 10 (58.8%) cats and bilateral thyroid enlargement in seven (41.2%). After levothyroxine treatment (median 133 µg/cat/day) in 15 cats, serum total T4 concentration increased and TSH fell. Treated cats became more alert and active, goiter resolved, azotemia resolved or improved, and two achieved remission of concurrent diabetes mellitus. Conclusions and relevance: This study broadens current knowledge of spontaneous hypothyroidism in adult cats, a condition that remains underrecognized in clinical practice. Atrophic hypothyroidism appears more common than previously recognized, although goitrous hypothyroidism was identified in more than 40% of cats. Spontaneous hypothyroidism should be considered in cats with unexplained azotemia and in diabetic cats with worsening glycemic control. Levothyroxine supplementation reliably improved or resolved clinical signs in all treated cats.

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.

Objectives: The aim of this study was to assess the short-term safety and efficacy of fenofibrate in controlling secondary hypertriglyceridemia in cats. Methods: This was a prospective cohort study. Seventeen adult cats with hypertriglyceridemia (serum triglycerides [TG] >160 mg/dl) were enrolled. Cats received a median dose of 5 mg/kg (range 3.2–6) fenofibrate (q24h PO) for 1 month. Serum TG, total cholesterol (TC), creatine kinase and liver enzymes (alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase) were evaluated before (t0) and after 1 month (t1) of fenofibrate treatment. Results: The causes of secondary hypertriglyceridemia were diabetes mellitus (DM; 29.4%), obesity (29.4%), hyperadrenocorticism (HAC) and DM (11.7%), HAC without DM (5.9%), hypersomatotropism (HST) and DM (5.9%), hypothyroidism (5.9%), long-term treatment with glucocorticoids (5.9%) and chylothorax (5.9%). Serum TG (t0 median 920 mg/dl [range 237–1780]; t1 median 51 mg/dl [range 21–1001]; P = 0.0002) and TC (t0 median 278 mg/dl [range 103–502]; t1 median 156 mg/dl [range 66–244]; P = 0.0001) concentrations showed a significant decrease after 1 month of fenofibrate treatment. Fifteen cats normalized their TG concentration at t1 (88.2%). Of the eight cats that were hypercholesterolemic at t0, six (75%) normalized their TC concentrations at t1. One of 17 cats (5.9 %) presented with diarrhea; the remaining 16 did not show any adverse effects. Conclusions and relevance: DM and obesity are the most common endocrine causes of secondary hyperlipidemia, although it can also be found in cats with HAC, HST or hypothyroidism. This study suggests that fenofibrate treatment was associated with reduction and normalization of TG and TC concentrations in cats with moderate and severe hypertriglyceridemia, regardless of the cause of secondary hypertriglyceridemia. Further work should focus on controlled studies with a greater number of cases.

Objectives: The aim of this study was to collect clinical information from owners of cats with hypersomatotropism (HS) distributed worldwide, assessing the impact of HS and its treatments on cats’ quality of life (QoL) and survival time. Methods: A survey focused on clinical presentation, diagnostic procedures, treatments, cats’ QoL and disease progression was distributed worldwide to owners of cats with HS. The owner’s perception of the cats’ QoL before and after or during treatment was defined using a score ranging from 1 (poor) to 5 (excellent). Improvement following treatment (IFT) was quantified using a score ranging from 1 (absent) to 5 (obvious). Different treatment groups, including at least five cases, were compared. Results: A total of 127 cats were included from at least 11 different countries. Among these, 120 (95%) were diabetic and 7 (5%) were not. Out of 120 diabetic cats, 55 (46%) were treated with insulin as a single treatment (INS). Other treatments were not mentioned to owners in 35/120 (29%) cases. The median QoL score at diagnosis was 2 (range 1–5) and improved after treatment in all groups. Cabergoline (4; range 1–5), radiotherapy (4; range 2–5) and hypophysectomy (5; range 4–5) showed better median IFT scores compared with INS (3; range 1–5) ( P = 0.046, P P P = 0.047) and was equal to radiotherapy IFT ( P = 0.32). No difference was found between cabergoline and radiotherapy IFT ( P = 0.99). The median survival time (MST) was 24 months (range 0–75 months). Cats treated with INS showed shorter MST (22 months; range 0–69 months) compared with cats treated with causal treatments combined (36 months; range 3–75 months) ( P = 0.04). Conclusions and relevance: Not all cats with HS will have diabetes mellitus. Causal treatments seem associated with the greatest improvements in perceived cats’ QoL and survival; such treatments should therefore be discussed with owners. Cabergoline could be an effective alternative management option.

Objectives: The aim of this study was to evaluate the safety and efficacy of cabergoline to control hypersomatotropism (HST) and diabetes mellitus (DM) in cats. Methods: This was a prospective cohort study. Twenty-three cats with HST and concurrent DM were enrolled. Cats received a dose of 10 μg/kg cabergoline q48h PO for 6 months. Serum insulin-like growth factor 1 (IGF-1) and fructosamine concentrations, insulin dose and Insulin Resistance Index (IRI) were measured at the time of diagnosis of HST and at the start of cabergoline treatment (t0), and 3 months (t1) and 6 months (t2) during cabergoline treatment. Results: A decrease and normalization of serum IGF-1 concentration was observed in 35% and 26% of cats, respectively. Median IGF-1 (t0: 1350 ng/ml [range 832–1501]; t1: 1284 ng/ml [range 365–1501]; t2: 1240 ng/ml [range 263–1501]; P = 0.016) decreased significantly. Twelve cats underwent diagnostic imaging of the pituitary area. The median pituitary height at t0 of cats that experienced an IGF-1 reduction (n = 5/12) was significantly lower compared with those that did not experience an IGF-1 reduction (n = 7/12) (3.2 mm [range 3.1–3.7] vs 6 mm [range 3.5–9.5]; P = 0.011). Median fructosamine (t0: 628 µmol/l [range 400–963]; t1: 404 µmol/l [range 249–780]; t2: 400 µmol/l [range 260–815]; P P P <0.0001) decreased significantly during cabergoline treatment. Eight cats achieved diabetic remission between months 1 and 6 of cabergoline treatment (median time to achieve remission: 3 months [range 1–6]). Three cats experienced asymptomatic hypoglycemia. Conclusions and relevance: Cabergoline was effective in normalizing IGF-1 concentration in 26% of cats. Cabergoline improved diabetes control and was associated with remission of DM in 35% of cases. Cabergoline could be a treatment option for cats with HST and DM, especially in those cases with a relatively small pituitary tumor.

Case summary: A 7-year-old spayed female domestic shorthair cat weighing 5 kg was referred with polyuria, polydipsia, lethargy, abdominal distension and dermatologic abnormalities. Diabetes mellitus was diagnosed and treatment was started with a diet for diabetic cats and insulin glargine (1 IU q12h SC). Hyperadrenocorticism (HAC) was suspected and diagnosed based on clinical signs, increased urinary cortisol:creatinine ratio, lack of suppression on low-dose dexamethasone suppression test and abdominal ultrasonography demonstrating bilateral adrenal enlargement. Oral cabergoline (10 μg/kg every other day) was initiated. After the second administration of cabergoline, the cat suffered from clinical hypoglycemia and no longer required insulin. One month after insulin withdrawal, blood work and urine analysis results showed normoglycemia, a normal serum fructosamine concentration (244 μmol/l) and normal urine analysis without glycosuria. Diabetic remission persisted until its death 7 months later. In addition, cabergoline treatment was associated with improvement in clinical signs such as lethargy, seborrhea, alopecia and abdominal distension. Relevance and novel information: To our knowledge, this is the first reported case of the use of cabergoline in a cat with HAC, as well as the first reported case of diabetic remission in a cat with HAC after cabergoline treatment. Cabergoline could be an alternative treatment for diabetic cats with pituitary-dependent HAC. Further work should focus on different protocols with greater number of cases.