Nesidioblastosis and Subsequent Diabetes Mellitus in a Dog with Hyperinsulinemic Hypoglycemia Treated with Partial Pancreatectomy.

A 6.5 yr old castrated male mixed-breed dog was presented for clinical signs associated with hypoglycemia. Hyperinsulinemic hypoglycemia was diagnosed as the cause of the persistent hypoglycemia. No obvious pancreatic mass was seen on abdominal computed tomography and exploratory laparotomy. A partial pancreatectomy was performed with the suspicion of an insulinoma-causing hyperinsulinemic hypoglycemia. Nesidioblastosis was diagnosed based clinical, biochemical, and histopathologic findings. There was beta cell hyperplasia and no evidence of neoplasia. The dog was euglycemic postoperatively after a partial pancreatectomy. Long-term follow-up after 2 yr revealed that the dog was diagnosed with diabetes mellitus.

Cytologic features of canine melanotroph and corticotroph pituitary adenomas.

BACKGROUND: The introduction of intraoperative cytology revolutionized neurosurgical procedures in human medicine, providing real-time diagnostic guidance to surgeons and contributing to improved patient outcomes. In the realm of veterinary medicine, the understanding of pituitary tumors in dogs and cats remains limited due to challenges in obtaining antemortem samples of central nervous system lesions. OBJECTIVES: The aim of this study was to describe the cytologic features of pituitary adenomas in 12 dogs that underwent hypophysectomy. METHODS: The series included nine melanotroph adenomas and three corticotroph adenomas. Definitive diagnosis was based on histopathology and immunohistochemistry. RESULTS: Cytologically, the adenomas had high numbers of bare nuclei and intact cells that were round to polygonal and situated individually or in small clusters. The intact cells had round to oval, eccentric nuclei with finely stippled chromatin and one to three prominent nucleoli and ample to abundant lightly basophilic to amphophilic, grainy cytoplasm with distinct borders, and variable numbers of discrete vacuoles. Mild-to-moderate anisocytosis and anisokaryosis, occasional binucleation, rare and atypical mitotic figures, and nuclear molding were also observed. CONCLUSIONS: The results suggest that intraoperative cytology of canine pituitary adenomas holds promise as a valuable diagnostic tool, aiding swift differentiation from other sellar masses before histologic confirmation. Cytologic characterization of pituitary adenomas in dogs is exceptionally rare in the scientific literature, making this study one of the first to offer a comprehensive description of these cytologic features.

Ionized calcium-to-phosphorus ratio predicts neoplasia in azotemic dogs: a retrospective study of 105 cases.

OBJECTIVE: To evaluate dogs with total hypercalcemia, azotemia, and normal serum phosphorus concentrations to determine whether a calcium-to-phosphorus ratio (Ca:P) or ionized Ca:P (iCa:P) could be utilized to predict underlying neoplasia. ANIMALS: 105 dogs were included in the study. Thirty-seven percent (n = 39) had known neoplasia, and 63% (66) had no evidence of neoplasia. PROCEDURES: A retrospective medical records search was performed. An observational cutoff of 2.5 for Ca:P and 0.33 for iCa:P was used for determining sensitivity and specificity between the neoplasia and nonneoplasia groups. RESULTS: Total hypercalcemia was higher in dogs with neoplasia compared to nonneoplastic cases of hypercalcemia. Ca:P of 2.5 had an 80% sensitivity and 46% specificity for predicting neoplasia. iCa:P of 0.33 had a 92% sensitivity and 77% specificity for predicting neoplasia in azotemic dogs. CLINICAL RELEVANCE: The sensitivity and specificity of Ca:P was low, making it an unreliable tool to predict neoplasia in this specific study population. However, iCa:P may have some usefulness in determining presence of neoplasia in patients with high calcium, azotemia, and normal phosphorus.

Clinical characteristics and outcome in 15 dogs treated with transsphenoidal hypophysectomy for nonfunctional sellar masses.

OBJECTIVE: To characterize the clinical features, neurological examination findings, diagnostic imaging results, histopathological findings, and outcome following transsphenoidal hypophysectomy (TSH) in dogs with nonfunctional sellar masses (NFSM). STUDY DESIGN: Multi-institutional retrospective study. METHODS: Medical records of dogs that underwent TSH for a NFSM were reviewed for clinical signs, physical and neurological examination findings, diagnostic imaging results, endocrine testing, surgery reports, and outcome. Magnetic resonance (MR) imaging was rereviewed, and tumors were classified using the previously described system according to pituitary tumor extension and vascular involvement. Owners of dogs that survived to discharge were contacted. RESULTS: The majority of dogs presented for mentation change (12/15). The mean pituitary to brain ratio (P/B ratio) was 1.05 (0.6-1.4). Eight dogs had a tumor imaging classification of 5B. Eleven dogs were diagnosed with a nonfunctional pituitary adenoma (NFPA). Perioperative mortality was 33% (5/15). The median survival for all dogs was 232 days (0-1658). When dogs that did not survive to discharge were excluded, the median survival time was 708 days. Seven of 10 dogs that survived the perioperative period received adjunctive therapy. Owner assessment of outcome was excellent (6/7) to good (1/7). CONCLUSION: The common presenting complaint for dogs with large NFSM causing mass effect was mentation changes. Dogs with NFPA that survived to discharge and received adjunctive therapy had good to excellent outcomes. CLINICAL SIGNIFICANCE: Transsphenoidal debulking with adjunctive therapy can be considered for the treatment of NFSM causing clinical signs of mass effect in dogs. Successful long-term outcomes are possible.

Medical errors: Experiences, attitudes and perspectives of incoming and outgoing final-year veterinary students in the USA.

BACKGROUND: Medical errors have an impact on veterinary patient safety. Studies in human medicine suggest that students can help prevent medical errors. However, there are no studies that address the role of veterinary students in patient safety. METHODS: An electronic survey was distributed to incoming final-year (IFY) and outgoing final-year (OFY) students at the Washington State University College of Veterinary Medicine. Response data were compared between class year groups with a Fisher's exact test and Mann-Whitney U test. RESULTS: The response rate was 26.8% (70/261). Most respondents (85.7%) reported being present during a medical error, and 60% reported causing a medical error. The OFY group indicated lower agreement with documenting an error in the patient record and whether all errors should be disclosed. The IFY group felt more distress surrounding potential errors and sequential career implications. Compared with the IFY group, the OFY group agreed more that errors occur frequently in veterinary medicine and disagreed more that hospital staffing is adequate to ensure patient safety. Open responses recognised a need for communication training and identified that the OFY group regarded errors more actionably, whereas the IFY group viewed errors more emotionally. CONCLUSION: Most veterinary students will experience medical errors prior to graduation, but some lack clarity around appropriate disclosure and documentation. Additional training on medical errors and error disclosure should be provided to veterinary students.

Functional Flexion Instability After Rotating-Platform Total Knee Arthroplasty.

BACKGROUND: We sought to define "at risk" loading conditions associated with rotating-platform total knee arthroplasty (TKA-RP) implants that predispose to insert subluxation and spinout and to quantify tolerances for flexion-extension gap asymmetry and laxity in order to prevent these adverse events. METHODS: Biomechanical testing was performed on 6 fresh-frozen cadaveric limbs with a TKA-RP implant with use of a gap-balancing technique, followed by sequential femoral component revision with variable-thickness polyethylene inserts to systematically represent 5 flexion-extension mismatch and asymmetry conditions. Each configuration was subjected to mechanical loading at 0°, 30°, and 60°. Rotational displacement of the insert on the tibial baseplate, lateral compartment separation, and insert concavity depth were measured with use of a digital caliper. Yield torque, a surrogate for ease of insert rotation and escape of the femoral component, was calculated with use of custom MATLAB code. RESULTS: Design-intended insert rotation decreased with increasing knee flexion angles in each loading configuration. Likewise, yield torque increased with increasing joint flexion and decreased with increasing joint laxity in all testing configurations. Insert instability and femoral condyle displacement were reproduced in positions of increasing knee flexion and asymmetrical flexion gap laxity. The depth of lateral polyethylene insert concavity determined femoral condylar capture and defined a narrow tolerance of <2 mm in the smallest implant sizes for flexion gap asymmetry leading to rotational insert instability. CONCLUSIONS: Decreased femoral-tibial articular surface conformity with increasing knee flexion and asymmetrical flexion gap laxity enable paradoxical motion of the femoral component on the upper insert surface rather than the undersurface, as designed. CLINICAL RELEVANCE: Mobile-bearing TKA-RP is a technically demanding procedure requiring a snug symmetrical flexion gap. As little as 2 mm of asymmetrical lateral flexion laxity can result in decreased conformity, condyle liftoff, and insert subluxation. Flexion beyond 30° decreases bearing surface contact area and predisposes to reduced insert rotation and mechanical malfunction.

Anicteric gallbladder rupture in dogs: 5 cases (2007-2013).

OBJECTIVE: To describe clinical, laboratory, and surgical findings in dogs with confirmed gallbladder rupture and in which serum total bilirubin concentration was within reference limits. DESIGN: Retrospective case series. ANIMALS: 5 dogs. PROCEDURES: Medical records were searched to identify dogs with gallbladder rupture that underwent treatment at the Kansas State University Veterinary Health Center from November 2007 through November 2013. Dogs were included if they had undergone abdominal ultrasonography, serum total bilirubin concentration was ≤ 0.4 mg/dL, and abdominal exploratory surgery confirmed the presence of gallbladder upture. RESULTS: An exploratory celotomy was performed in all dogs because of ultrasonographic findings of mild to marked abdominal effusion and either an unidentifiable gallbladder (n = 1 dog) or a distended gallbladder with a suspected gallbladder mucocele (4 dogs). Serum total bilirubin concentration was within reference limits (median, 0.2 mg/dL; range, 0.1 to 0.4 mg/dL; reference range, 0.1 to 0.4 mg/dL) in all dogs before surgery. In 1 dog, bile acids concentrations in serum and in peritoneal fluid were compared and the results (48 µmol/L and 1,070 µmol/L, respectively) were supportive of the diagnosis of gallbladder rupture. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that even when serum total bilirubin concentration is within reference limits, gallbladder rupture should be considered in dogs with acute signs of abdominal pain when a mucocele is suspected on abdominal imaging and free abdominal fluid is present. Results suggested that a comparison of serum to peritoneal fluid bile acids concentrations may provide additional support for a diagnosis of gallbladder rupture.