Evaluation of hemostatic derangements associated with canine anaphylaxis and the relationship to syndrome severity

Objective

To describe hemostatic derangements associated with canine anaphylaxis and to assess for association with syndrome severity.

Design

Prospective observational study.

Setting

University teaching hospital.

Animals

Twenty-seven client-owned dogs, recruited from November 2018 to January 2022, diagnosed with anaphylaxis of varying severity were included. Study inclusion required presentation <6 hours after initiation of clinical signs, no medications or history of illness within the prior 2 weeks, lack of comorbidities expected to affect hemostasis, and lack of a disease state that could alternatively explain the clinical presentation.

Interventions

Blood samples were collected within the first hour of presentation for CBC, serum biochemistry, prothrombin time (PT), activated partial thromboplastin time (aPTT), and viscoelastic coagulation testing for use with a cartridge-based point-of-care device.

Measurements and main results

Clotting time and clot formation time were prolonged, alpha angle and maximum clot firmness were decreased, PT and aPTT were prolonged, and platelet counts were lower in severe cases compared to mild and moderate cases. There were no differences for any parameter between mild and moderate cases. The presence or absence of abdominal effusion was not associated with hemostatic status.

Conclusions

Global hemostatic derangements consistent with hypocoagulability are a prominent feature of severe anaphylaxis in dogs and should be considered for routine evaluation.     

Progression of Femoropatellar Osteochondrosis in Nine Young Horses Clinical, Radiographic and Arthroscopic Findings

The clinical and radiographic progression, and arthroscopic findings for nine young horses (<1 year of age) with femoropatellar osteochondrosis (OCD) are presented. Horses had a 2 to 12 week history of bilateral (8 horses) or unilateral (1 horse) hindlimb lameness. The most consistent clinical signs included femoropatellar joint distention and bilateral hindlimb lameness. At the onset of clinical signs, radiographic lesions were not present (4 horses) or subtle (5 horses), but were easily identified on radiographs taken 4 to 24 weeks later. Arthroscopic surgery was delayed until radiographic changes became obvious. Surgical findings in 20 femoropatellar joints were most commonly osteochondral "flaps" located on the proximal lateral trochlear ridge of the femur and were larger than had been indicated by the radiographs. Eight horses were being used for their intended purpose, which was racing (3 horses were racing and 3 were in race training), dressage (1 horse) or pleasure riding (1 horse). One horse required a second surgery when similar lesions developed in the opposite stifle, and was euthanatized 2 months later because of persistent lameness. Once clinical signs are observed, osteochondrosis lesions of the distal femur can progress in foals younger than 9 months of age and the full extent of the radiographic lesion may take several weeks to develop.     

Radiographic and Histologic Changes After Thoracolumbar Disc Curettage

Forty-eight thoracolumbar disc spaces were approached by a dorsolateral muscle-separating technique in six mature dogs. Twenty-four of the discs were fenestrated and curetted, and the changes were followed radiographically and histologically for 16 weeks. Disc space collapse was visible radiographically immediately after the surgical procedure, and those disc spaces remained narrow throughout the observation period. Histologically, there was evidence of chondrocyte activation within 2 weeks in the excavated disc spaces. By 16 weeks, fibrocartilage had filled the void in the curetted disc spaces.     

Arthroscopic Subchondral Bone Plate Microfracture Technique Augments Healing of Large Chondral Defects in the Radial Carpal Bone and Medial Femoral Condyle of Horses

OBJECTIVE: To evaluate the effect of arthroscopic subchondral bone microfracture on healing of large chondral defects in horses. STUDY DESIGN: Short- (4 months) and long-term (12 months) in vivo experimental chondral defect model. ANIMALS: 10 horses, aged 2 to 5 years. METHODS: Each horse had a 1 cm2 full-thickness chondral defect created in both radial carpal bones and both medial femoral condyles. One carpus and one femoral condyle of each horse had the subchondral bone plate under the defect perforated using an orthopedic awl. All horses were exercised, five horses were evaluated after 4 months and five horses after 12 months. Gross, histologic, and histomorphometric examination of defect sites and repair tissues was performed, as was collagen typing of the repair tissue. RESULTS: On gross observation a greater volume of repair tissue filled treated defects (74%) compared with control defects (45%). Histomorphometry confirmed more repair tissue filling treated defects, but no difference in the relative amounts of different tissue types was observed. There was an increased percentage of type II collagen in treated defects compared with control defects and evidence of earlier bone remodeling as documented by changes in porosity. CONCLUSIONS: In full-thickness chondral defects in exercised horses, treatment with subchondral bone microfracture increased the tissue volume in the defects and the percentage of type II collagen in the tissue filling the defects when compared to nontreated defects. CLINICAL RELEVANCE: No negative effects of the microfracture technique were observed and some of the beneficial effects are the basis for recommending its use in patients cases with exposed subchondral bone.     

COMPARISON OF UPPER GASTROINTESTINAL RADIOGRAPHIC FINDINGS TO HISTOPATHOLOGIC OBSERVATIONS: A RETROSPECTIVE STUDY OF 41 DOGS AND CATS WITH SUSPECTED SMALL BOWEL INFILTRATIVE DISEASE (1985 to 1990)

It was the intent of this study to define which, if any, radiographic observations corresponded with specific causes of diffuse infiltrative small bowel disease and if radiographic findings could differentiate inflammatory disease from neoplastic disease and either of them from normal. Bowel spasticity, luminal narrowing, and thumbprinting tend to indicate the presence of tumor more often than inflammatory disease. Increased bowel gas in cats and barium adhesion in dogs and cats suggest that a component of enteritis is present. Decreased bowel gas in dogs is more often associated with obstructive disease, but is not helpful in differentiating diffuse inflammatory disease from diffuse neoplastic disease. While several observations that can foster differentiation of neoplastic from inflammatory disease were found, this study also indicated that the UGI lacks a high degree of predictive value other than to indicate the presence of infiltrative small bowel disease.     

TECHNETIUM-99M AND IODINE-131 THYROID SCINTIGRAPHY IN NORMAL AND RADIOTHYROIDECTOMIZED COCKATIELS (NYMPHICUS HOLLANDICUS)

Thyroid scintigraphy using sodium ^99mTechnetium pertechnetate (⁹⁹TcO₄-) was performed in normal and radiothyroidectomized cockatiels ( Nymphicus hollandicus ). ¹³¹I scintigraphy was performed in the course of ablating the thyroid glands. The thyroid glands in normal birds were clearly visualized, but were not individually resolvable. Thyroid glands were not visualized in thyroid-ablated birds. With ^99mTcO₄ scans, thyroid (or other region of interest)/body count density ratios were used for comparisons of normal and thyroid-ablated birds. Normal ^99mTcO₄- thyroid/body ratios (mean +/− SD) for the dorsal and lateral views were 1.83 +/− 0.31 and 1.70 +/− 0.34 respectively. Pertechnetate thyroid/body count density ratios decreased (to 0.93 -/−0.14 and 0.88 +/− 0.12 for dorsal and lateral views respectively) after thyroid ablation, while crop/body ratios increased. ^99mTcO₄- thyroid scintigraphy, therefore, was capable of detecting hypofunctional thyroid abnormalities in ¹³¹I radiothyroidectomized cockatiels.