Oliver Waite

Naturally occurring hypercortisolism in dogs is commonly investigated in primary care practice. However, there is a poor understanding of the preference and interpretation of diagnostic tests by Australian veterinarians. This study aimed to investigate the diagnostic processes used by Australian primary care veterinarians via an anonymous online survey consisting of multiple-choice and short-answer questions. The survey was completed by 399 respondents. When hypercortisolism was suspected, 392 performed adrenal function testing, while seven used treatment trials. With consistent clinical signs but no clinicopathological abnormalities, 354 performed screening tests, and 312 in dogs with consistent clinicopathological abnormalities but no clinical signs. For veterinarians who performed function testing, 296 used the same screening tests regardless of the magnitude of pre-test suspicion; 266 used either an adrenocorticotropic hormone (ACTH) stimulation test or low-dose dexamethasone suppression test (LDDST) alone. Even in the absence of financial constraints, 158 of 399 respondents almost never attempted differentiation between ACTH-dependent and ACTH-independent disease. For those attempting differentiation, 178 used abdominal ultrasound and 102 used LDDST. Approximately half of all respondents indicated that specialist referral was not offered to any of the preceding 10 cases suspected of hypercortisolism. Hypercortisolism is frequently diagnosed in dogs without consistent clinical signs or without performing routine clinical pathology tests, raising concerns for overdiagnosis. A large proportion of respondents rarely attempted to differentiate between causes of hypercortisolism, possibly affecting long-term management and prognosis. Referral to a specialist is rare, suggesting the condition is predominantly managed in primary care practice.

Osteoblastic metastases occur secondary to malignant epithelial tumours, and lead to marked periosteal hyperostosis and medullary sclerosis. These are rarely reported in dogs. A 7-year-old, neutered, female labrador retriever × standard poodle presented with a 4-week history of progressive right hindlimb lameness, pyrexia and thoracolumbar pain. A mammary mass was identified, with cytology indicating a malignant carcinoma. Computed tomography demonstrated extensive primary osteoblastic lesions affecting vertebrae and proximal appendicular bones, alongside pulmonary and lymph node metastasis. Given the guarded prognosis, euthanasia was elected by the owner. Postmortem examination revealed irregular periosteal proliferation associated with metastatic mammary carcinoma in the scapula, humerus, femur, ribs, thoracic and lumbar vertebrae and bony induration of the medulla of the long bones. This case advances the understanding of skeletal metastases in dogs, which can often be misdiagnosed, and offers guidance for clinical and diagnostic approaches.

INTRODUCTION: Diabetes mellitus (DM) in cats imposes significant caregiver burdens, with 20% of all diabetic cats reportedly dead ≤ 30 days after diagnosis. Risk factors for cats not receiving anti-hyperglycemic therapy (AHT) are unreported. Studies evaluating early mortality in cats with DM who receive AHT are limited.

OBJECTIVES/HYPOTHESIS: Report risk factors for diabetic cats failing to receive AHT, and analyze factors associated with mortality ≤ 30 days following DM diagnosis in cats starting AHT.

ANIMALS: 375 cats under United Kingdom primary veterinary care with a first lifetime diagnosis of DM in 2019.

METHODS: Anonymized retrospective cohort study using electronic health records from VetCompass. Multivariable logistic regression and Cox proportional hazards models were performed, including risk factors (p < 0.2) associated with cats not receiving AHT and ≤ 30-day mortality when receiving AHT, respectively.

RESULTS: Exactly 65/375 (17.3%) diabetic cats did not receive AHT. In cats that started AHT (n = 310), estimated ≤ 30-day mortality was 10.0% (95% CI 7.1–13.8). Cats ≥ 15.0 years had significantly increased odds of not receiving AHT (OR 2.6 [95% CI 1.1–6.0], p = 0.024) (Table 1) and also increased ≤ 30-day mortality hazard after starting AHT (HR 3.5 [95% CI 1.2–10.1], p = 0.019) (Table 2). Presenting clinical signs and co-morbidities were not associated with ≤ 30-day mortality (p > 0.05).

CONCLUSIONS AND CLINICAL IMPORTANCE: In this population, almost 20% of diabetic cats were untreated, and greater age was a risk factor for failure to receive AHT and increased ≤ 30-day mortality. These results provide benchmarking information to assess whether outcomes change following the introduction of sodium-glucose cotransporter-2 inhibitors as treatments for feline DM.
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Background
Diabetes mellitus (DM) is a common endocrinopathy in cats. General population epidemiology and mortality studies on DM are lacking.

Objectives
Describe the incidence, prevalence, risk factors, and mortality for DM in cats under primary veterinary care in the United Kingdom (UK).

Animals
Random sample of 1053 confirmed DM cases from 1 255 130 cats in VetCompass.

Methods
Retrospective cohort study with a nested case–control study. Period prevalence and incidence risk of DM for 2019 were calculated. Multivariable logistic regression modeling was used to identify risk factors for DM.

Results
Annual prevalence was 0.39% (95% confidence interval [CI]: 0.37–0.42). Incidence risk (2019) was 0.14% (95% CI, 0.13–0.16). Mean age and median adult body weight of incident cases diagnosed with DM was 11.8 ± 3.5 years (n = 371) and 5.9 kg (interquartile range: 4.6–7.1, n = 327). Odds of DM were increased in cats ≥ 9.0 years (odds ratio [OR]: 5.11, CI, 4.10–6.24) compared with cats 4.5–9.0 years. Burmese (OR: 2.07, CI, 1.29–3.31) and Burmillas (OR: 8.30, CI, 2.59–26.62) had increased odds, whereas Bengals (OR: 0.24, CI: 0.06–0.98) and Ragdolls (OR: 0.11, CI: 0.02–0.80) had decreased odds of DM compared with crossbreeds. Of 51.2% (192/375) cats dead within 3 years of diagnosis, 93.0% (176/192) were euthanized; 19.7% (35/178) were euthanized ≤ 3 days after diagnosis.

Conclusions and Clinical Importance
Almost 1/250 cats in the UK live with DM annually. Burmillas were predisposed to DM, and protection against DM was shown in Bengals and Ragdolls. Early mortality associated with DM diagnosis in cats is high.