CASE DESCRIPTION A 13-year-old neutered male Abyssinian cat with a 4-month history of right forelimb edema and multifocal crusting lesions at the distal aspect of the antebrachium was referred to a veterinary teaching hospital for evaluation. Extensive hemorrhage from the lesions had been observed after self-grooming, and findings on histologic examination of a skin biopsy sample prior to referral were consistent with atypical dermal hemodynamics and inflammation. CLINICAL FINDINGS Diffuse pitting edema and multifocal, 3- to 4-mm-diameter sanguineous crusting lesions affecting the antebrachium were observed distal to a pulsatile subcutaneous mass in the right elbow joint region that had a palpable thrill and auscultable bruit. No systemic abnormalities were detected. TREATMENT AND OUTCOME Contrast-enhanced CT angiography with 3-D reconstruction identified an arteriovenous fistula with a large aberrant vessel coursing distally. Surgical ligation of an arterialized vein distal to the fistula without en bloc resection led to resolution of all clinical signs. The vascular anomaly was no longer patent when diagnostic imaging was repeated 5 months after surgery. CLINICAL RELEVANCE Acquired arteriovenous fistulas can lead to bleeding skin lesions affecting the antebrachium in cats. Surgical ligation of an aberrant reverse-shunting vein distal to the fistula successfully resolved clinical signs in the cat of this report and may warrant investigation as a treatment option in cats with this condition.

Objective: To report perioperative characteristics, complications, histopathologic diagnosis and outcome in cats undergoing surgical treatment for primary hyperparathyroidism (PHPT). Study design: Multi-institutional, retrospective case series. Animals: Thirty-two client-owned cats. Methods: Medical records of cats treated with surgical removal of 1 or more parathyroid gland(s) with confirmed histopathologic evaluation were reviewed. Cats were divided into preoperative ionized calcium (iCa) groups corresponding to the 33rd, 67th, and 100th percentiles of the preoperative iCa results of the study population. Follow-up consisted of phone conversation with owners or primary veterinarian. Results: Ionized calcium was above reference range in all cats (median 1.8 mmol/L [interquartile range, 1.5-1.9]). Abnormal tissue was excised after cervical exploration in all cats. The most common histopathologic diagnoses were parathyroid adenoma in 20 of 32 (62.5%) cats and parathyroid carcinoma in 7 of 32 (21.9%) cats. At discharge, 6 of 32 (18.8%) cats had hypercalcemia, 5 of 32 (15.6%) had hypocalcemia, and 21 of 32 (65.6%) were normocalcemic. Preoperative iCa did not correlate with postoperative iCa. The median follow-up time was 332 days (range, 7-3156). Overall median survival time was 1109 days (95% CI, 856-1332). Survival time was not associated with preoperative iCa group, hypocalcemia at discharge, hypercalcemia at discharge, or diagnosis of carcinoma. Conclusion: In this cohort of cats, parathyroid adenoma was the most common cause of PHPT, and surgical treatment resulted in very good median survival time. Preoperative iCa was not predictive of postoperative hypocalcemia. Clinical significance: Surgical parathyroidectomy for treatment of PHPT in cats provides a favorable prognosis.

Objective: To report outcomes following surgical treatment of hepatic abscessation in dogs. Study design: Retrospective.Animals: Thirty-eight dogs. Methods: Records from 6 institutions were evaluated for dogs undergoing surgical treatment for hepatic abscessation between 2010 and 2020. Signalment, clinical signs, medical therapy, surgical treatment, and postoperative outcome was obtained from medical records. Long-term outcome was recorded when possible. Median survival time was assessed using the Kaplan-Meier productlimit method.Results: Peritoneal effusion was documented in 32/38 dogs preoperatively, with septic peritonitis confirmed in 21/23 samples. Liver lobectomy was the most common surgery (27 dogs). A single organism was cultured in 24/35 dogs, most commonly Escherichia coli. Hepatic neoplasia was identified in 11/36 dogs. Dogs were hospitalized for a median of 5 days (range, 3-17) with complications recorded in 21 dogs (regurgitation, aspiration pneumonia, and pancreatitis most commonly). Two dogs died intraoperatively, and 6 dogs died prior to discharge. Median survival time for dogs surviving to discharge was 638 days. Of these, 19 were lost to follow up a median of 301 (range, 3-1418) days postoperatively and 11 died a median of 291 (range, 7-1292) days postoperatively. No abscess recurrence was noted. Conclusion: Septic peritonitis was a common sequela to hepatic abscessation.Perioperative complications were recorded in approximately one-third of dogs. In dogs surviving the postoperative period, long-term prognosis was good.Clinical significance: Dogs treated surgically for hepatic abscessation have a high risk of perioperative complications but favorable long-term prognosis and apparent low risk of recurrence.

CASE DESCRIPTION A 5-year-old spayed female domestic shorthair cat was evaluated because of an acute onset of dyspnea and open-mouthed breathing. CLINICAL FINDINGS Thoracic radiography revealed pleural effusion and signs consistent with restrictive pleuritis, and results of preoperative CT were consistent with diffuse, severe restrictive pleuritis, bilateral pleural effusion, and pulmonary atelectasis. Thoracocentesis yielded a red, turbid fluid that was identified as chylous effusion with chronic inflammation. TREATMENT AND OUTCOME Exploratory thoracotomy revealed diffuse, severe fibrous adhesions between the mediastinum, heart, lung lobes, and thoracic wall, with a thick fibrous capsule enveloping all lung lobes. Surgical treatment consisted of complete pleural decortication, pericardiectomy, and thoracic omentalization. The cat remained hospitalized for 6 days, receiving oxygen supplementation, multimodal analgesia, and supportive care. Long-term home care consisted of prednisolone administration, rutin supplementation, and provision of a low-fat diet. At recheck examinations 3-, 7-, and 20-weeks postoperatively, the cat remained tachypneic, but was otherwise clinically normal without dyspnea or respiratory distress. Follow-up thoracic radiography revealed improved pulmonary expansion, decreased pleural effusion, and resolved pneumothorax. CLINICAL RELEVANCE Surgical management of fibrosing pleuritis secondary to idiopathic chylothorax in cats has historically resulted in poor outcomes. This report details the first successful use of complete decortication in the surgical management of severe fibrosing pleuritis in a cat.

Two dogs and 1 cat were referred to a tertiary veterinary center for the consultation and treatment of limb edema, variable dermal sanguineous crusting lesions, and intermittent lameness. A peripheral arteriovenous anomaly (PAA) was diagnosed via computed tomographic angiography (CTA) in each case. Arteriography enabled further evaluation of the PAA with confirmation of a dominant outflow vein. Dominant outflow vein occlusion was achieved by direct ligation in 1 dog and retrograde transvenous glue embolization in the cat and other dog. Repeat arteriography demonstrated resolution of arteriovenous shunting. Presenting clinical signs resolved in all animals. The previously identified aberrant vessels in 1 dog were not identified after CTA 40 days postoperatively. No postoperative complications or recurrence was identified in any case during the 6‐ to 55‐month follow‐up period.