Comparison of pharmacodynamics between insulin glargine 100 U/mL and insulin glargine 300 U/mL in healthy cats

Insulin glargine (IGla) is a synthetic human-recombinant insulin analog that is used routinely in people as a q24h basal insulin. The 300 U/mL (U300) formulation of IGla is associated with longer duration of action and less within-day variability, making it a better basal insulin compared with the 100 U/mL (U100) formulation. We hypothesized that in healthy cats, IGlaU300 has a flatter time-action profile and longer duration of action compared with IGlaU100. Seven healthy neutered male, purpose-bred cats were studied in a randomized, crossover design. Pharmacodynamics of IGlaU100 and IGlaU300 (0.8 U/kg, subcutaneous) were determined by the isoglycemic clamp method. The time-action profile of IGlaU300 was flatter compared with IGlaU100 as demonstrated by lower peak (5.6 ± 1.1 mg/kg/min vs 8.3 ± 1.9 mg/kg/min, respectively; P = 0.04) with no difference in total metabolic effect (ME; P = 0.7) or duration of action (16.8 h ± 4.7 h vs 13.4 h ± 2.6 h; P = 0.2). The greater fraction of ME in the 12- to 24-h period postinjection (35 ± 23% vs 7 ± 8% respectively; P = 0.048) and lower intraday GIR% variability (7.8 ± 3.7% vs 17.4 ± 8.2% respectively; P = 0.03) supports a flatter time-action profile of IGlaU300. There were no differences in onset and end of the action. In summary, although both formulations have a similar duration of action that is well below 24 h, the ME of IGlaU300 is more evenly distributed over a 24 h period in healthy cats, making it a better candidate for once-daily injection in diabetics compared with IGlaU100.

Treatment of a heart base tumor and chylothorax with endovascular stent, stereotactic body radiation therapy, and a tyrosine kinase inhibitor in a dog

An 8-year-old 28-kg male castrated rough collie was evaluated for persistent chylothorax secondary to right atrial mass. Cardiac ultrasound and computed tomography revealed a right atrial intra- and extraluminal mass with partial obstruction of the cranial vena cava and secondary chylothorax. Vascular stent placement was elected to alleviate cranial vena cava obstruction and secondary chylothorax. An 18 mm × 180 mm self-expanding stent was deployed in the region of the stricture, spanning the cranial vena cava and right atrium. An intrathoracic drainage catheter and subcutaneous port were placed within the right hemithorax, and antiplatelet therapy was initiated. Four weeks later, the dog underwent stereotactic body radiation therapy. Three months following treatment, the dog was diagnosed with supraventricular tachycardia and received antiarrhythmic therapy and antiangiogenic/antiproliferative medication (Palladia™). Subsequent evaluations confirmed the resolution of arrhythmia and pleural effusion. Combined vascular stent placement and stereotactic body radiation therapy for the treatment of a right atrial intraluminal and extraluminal mass leading to cranial vena cava compression and subsequent chylothorax may lead to long-term survival. A good outcome was achieved in this patient due to resolution of pleural effusion, as well as cytoreduction and presumably delayed progression of tumor growth.

Histopathological Terminology Standards for the Reporting of Prostatic Epithelial Lesions in Dogs

The terminology applied to canine prostatic epithelial lesions, especially carcinomas, is currently not standardized and this hampers the ability of pathologists to study the biological and clinical significance of these lesions. The aim of this review is to present the essential histomorphological diagnostic attributes of a wide spectrum of prostatic epithelial lesions in dogs. In addition to the traditionally recognized prostatic hyperplasia, hormonal atrophy, prostatitis, squamous metaplasia, adenocarcinoma and transitional cell (urothelial) carcinoma, new entities are described and discussed in order to provide veterinary pathologists with a basic atlas of common histological lesions of the canine prostate that is comprehensive and easy to use.

Frequency of post-traumatic osteoarthritis in dogs after repair of a humeral condylar fracture

The frequency of post-traumatic osteoarthritis (PTO) in the dog after repair of a humeral condylar fracture (HCF) and the relationship of fracture reduction to outcome is unknown. The objectives of this study were to determine the frequency of PTO in dogs after HCF repair and to determine the relationship between fracture reduction, limb function and follow-up osteoarthrosis (OA) score. All dogs were evaluated by physical and radiographic examinations and dogs with unilateral fracture repair were also examined by force platform gait analysis. Initial and follow-up radiographs were scored for reduction and evidence of osteoarthrosis using previously published grading scales. This study evaluated 15 fractures in 13 dogs with a mean follow-up time of 43 months. Osteoarthrosis developed or progressed radiographically in all elbows. Peak vertical force (PVF) was significantly reduced (p <0.01) in the affected limb, however vertical impulse (VI) did not differ (p = 0.12) when compared to the opposite normal limb. Pain-free range of motion was reduced in flexion (p <0.01), but not in extension (p = 0.98) when compared to the normal limb. Fracture reduction score did not correlate with follow-up OA score (p = 0.07), PVF (p = 0.40), VI (p = 0.72), flexion (p =0.50), or extension (p = 0.62). Due to the high incidence of PTO, owners should be warned of the possibility of declining limb function over time despite near anatomic reduction.

Effect of Laparoscopic-assisted Gastropexy on Gastrointestinal Transit Time in Dogs

Background

Prophylactic gastropexy has been promoted as a means of preventing gastric volvulus during gastric dilatation and volvulus (GDV) syndrome. Little is known about the impact of gastropexy on gastrointestinal transit time.

Hypothesis

Laparoscopic‐assisted gastropexy (LAG) will not alter gastrointestinal transit times when comparing gastric (GET), small and large bowel (SLBTT), and whole gut transit times (TTT) before and after surgery.

Animals

10 healthy client‐owned large‐breed dogs.

Methods

Prospective clinical trial. Before surgery, all dogs underwent physical examination and diagnostic evaluation to ensure normal health status. Dogs were fed a prescription diet for 6 weeks before determination of gastrointestinal transit with a wireless motility capsule. LAG was then performed, and dogs were fed the diet for 6 additional weeks. Measurement of transit times was repeated 6 weeks after surgery.

Results

Ten dogs of various breeds at‐risk for GDV were enrolled. No complications were encountered associated with surgery or capsule administration. There were no significant differences in GET 429 [306–1,370] versus 541 [326–1,298] (P = 0.80), SLBTT 1,243 [841–3,070] versus 1,540 [756–2,623] (P = 0.72), or TTT 1,971 [1,205–3,469] versus 1,792 [1,234–3,343] minutes (median, range) (P = 0.65) before and after LAG.

Conclusions and Clinical Importance

An effect of LAG on gastrointestinal transit time was not identified, and wireless motility capsule can be safely administered in dogs after LAG.

Evaluation of Weight Change During Carboplatin Therapy in Dogs With Appendicular Osteosarcoma

Background

The prevalence of cancer cachexia in veterinary medicine has not been studied widely, and as of yet, no definitive diagnostic criteria effectively assess this syndrome in veterinary patients.

Objectives

(1) To determine the patterns of weight change in dogs with appendicular osteosarcoma treated with amputation and single‐agent carboplatin during the course of adjuvant chemotherapy; and (2) to determine whether postoperative weight change is a negative prognostic indicator for survival time in dogs with osteosarcoma.

Animals

Eighty‐eight dogs diagnosed with appendicular osteosarcoma. Animals were accrued from 3 veterinary teaching hospitals.

Methods

Retrospective, multi‐institutional study. Dogs diagnosed with appendicular osteosarcoma and treated with limb amputation followed by a minimum of 4 doses of single‐agent carboplatin were included. Data analyzed in each patient included signalment, tumor site, preoperative serum alkaline phosphatase activity (ALP), and body weight (kg) at each carboplatin treatment.

Results

A slight increase in weight occurred over the course of chemotherapy, but this change was not statistically significant. Weight change did not have a significant effect on survival. Institution, patient sex, and serum ALP activity did not have a significant effect on survival.

Conclusions and Clinical Importance

Weight change was not a prognostic factor in these dogs, and weight loss alone may not be a suitable method of determining cancer cachexia in dogs with appendicular osteosarcoma.

Evaluation of optimal water fluoridation on the incidence and skeletal distribution of naturally arising osteosarcoma in pet dogs

Experimental toxicological studies in laboratory animals and epidemiological human studies have reported a possible association between water fluoridation and osteosarcoma (OSA). To further explore this possibility, a case-control study of individual dogs evaluated by the UC Davis Veterinary Medical Teaching Hospital was conducted using ecologic data on water fluoridation based on the owner's residence. The case group included 161 dogs with OSA diagnosed between 2008-2012. Two cancer control groups included dogs diagnosed with lymphoma (LSA) or hemangiosarcoma (HSA) during the same period (n = 134 and n = 145, respectively). Dogs with OSA were not significantly more likely to live in an area with optimized fluoride in the water than dogs with LSA or HSA. Additional analyses within OSA patients also revealed no significant differences in age, or skeletal distribution of OSA cases relative to fluoride status. Taken together, these analyses do not support the hypothesis that optimal fluoridation of drinking water contributes to naturally occurring OSA in dogs.

Early tumor response to intraarterial or intravenous administration of carboplatin to treat naturally occurring lower urinary tract carcinoma in dogs

Background

Survival times and tumor responses associated with malignant neoplasia of the lower urinary tract are poor despite the vast array of current treatments. Therefore, the evaluation of alternative treatments, such as intraarterial administration of chemotherapy (IAC) should be considered.

Objective

To describe a technique for superselective catheterization for IAC and to evaluate initial tumor response by ultrasonography after both IAC and intravenous administration of chemotherapy (IVC).

Animals

Client‐owned dogs with lower urinary tract neoplasia treated with either IVC (n = 15) or IAC (n = 11).

Methods

Retrospective study. An arterial approach via the carotid or femoral artery was utilized to obtain superselective access and administer chemotherapy in the IAC cases. Medical record review was performed, data were recorded, and recorded variables were evaluated statistically.

Results

Intraarterial chemotherapy was successfully administered in all cases. There was a significantly greater decrease in longest unidimensional measurement in the IAC group as compared to the IVC group (P = .013). The IAC group was also significantly more likely to have a tumor response as assessed by modified RECIST guidelines (P = .049). Dogs in the IAC group were significantly less likely to develop anemia (P = .001), lethargy (P = .010) and anorexia (P = .024).

Conclusion and Clinical Importance

This study demonstrated the feasibility and efficacy of performing IAC for lower urinary tract neoplasia. Further investigation is necessary as the follow‐up time was short and the impact on long‐term outcome and survival was not determined.

Paraneoplastic hypertrophic osteopathy in 30 dogs

Paraneoplastic hypertrophic osteopathy (pHO) is known to occur in both canine and human cancer patients. While the pathology of pHO is well-described in the dog, very little information exists regarding the true clinical presentation of dogs affected with pHO. The primary objective of this study was to provide a more comprehensive clinical picture of pHO. To this end, we retrospectively identified 30 dogs and recorded data regarding presenting complaints and physical examination (PE) findings on the date of pHO diagnosis. As a secondary objective, any blood test results were also collected from the computerized records. The most common clinical signs included leg swelling, ocular discharge and/or episcleral injection, lameness, and lethargy. The most common haematological and serum biochemical abnormalities included anaemia, neutrophilia and elevated alkaline phosphatase. In addition to presenting a more detailed clinical description of pHO in the dog, these data support the previously described haematological, serum biochemical and PE abnormalities published in individual case reports.