Presumptive pseudohypoaldosteronism secondary to chronic urinary tract obstruction from sloughed urinary bladder mucosa and urinary tract infection in a cat

Objective – To describe a case of presumptive secondary pseudohypoaldosteronism (PHA) in a cat with urinary tract infection and chronic urethral obstruction. The obstruction was believed to have resulted from sloughed urinary bladder mucosa secondary to pressure necrosis. Case Summary – A 5‐year‐old, 4 kg, castrated male Siamese cat presented for vomiting and stranguria. Medical history included a perineal urethrostomy for urethral obstruction. Physical examination revealed a large, painful, nonexpressible urinary bladder. Point‐of‐care testing demonstrated electrolyte derangements consistent with a postrenal azotemia and metabolic acidosis. Results of urine culture was positive for bacterial growth. Diagnostic imaging revealed presence of retroperitoneal fluid, marked urinary bladder wall thickening, bilateral hydroureter, mild bilateral pyelectasia, and small nephroliths. The patient was treated for a urinary tract obstruction and infection. In the 3 weeks following initial discharge, the patient was evaluated on multiple occasions for lethargy, intermittent vomiting, inappropriate urination, and progressive polyuria and polydipsia. Although the urinary bladder was easily expressed during repeat examinations, it was persistently distended and subjectively thickened upon palpation. Repeat ultrasound of the urinary tract showed evidence of sloughed tissue in the bladder lumen, likely secondary to chronic urethral obstruction and pressure necrosis. A cystotomy was performed to remove the necrotic tissue, and a revised perineal urethrostomy was done due to a partial urethral stricture. Bladder biopsies were obtained at this time. Postoperatively, the cat was reported by the owners to be urinating normally but continued to be polyuric and polydipsic in the week following discharge. One week after surgery, the cat presented in hypovolemic shock with laboratory findings consistent with a presumptive diagnosis of secondary PHA. New or Unique Information Provided – PHA has not been reported previously in a cat. This case report suggests that aldosterone resistance should be considered in cats with consistent laboratory findings and a history of documented obstructive uropathy and urinary tract infection.     

The influence of crystalloid type on acid–base and electrolyte status of cats with urethral obstruction

Objective: To compare the effect of a balanced isotonic crystalloid solution with that of 0.9% sodium chloride on the acid–base and electrolyte status of cats with urethral obstruction.
Design: Randomized prospective clinical trial.
Setting: Academic veterinary emergency room.
Animals: Sixty-eight cats with naturally occurring urethral obstruction.
Interventions: Cats were randomized to receive either a balanced isotonic crystalloid solution (Normosol-R, n =39) or 0.9% sodium chloride ( n =29) for fluid therapy. Baseline venous blood gas and blood electrolyte values were obtained at the time of admission and at intervals during the course of therapy.
Measurements and main results: Baseline values were similar between groups. Cats receiving Normosol-R had a significantly higher blood pH at 12 hours, a significantly greater increase in blood pH from baseline at 6 and 12 hours, as well as a significantly higher blood bicarbonate concentration at 12 hours and a significantly greater increase in blood bicarbonate from baseline at 6 and 12 hours. Conversely, the increase in blood chloride from baseline was significantly higher at 2, 6, and 12 hours in cats receiving 0.9% sodium chloride. There were no significant differences in the rate of decline of blood potassium from baseline between groups. Subgroup analysis of hyperkalemic cats (K⁺>6.0 mmol/L) and acidemic cats (pH<7.3) yielded similar findings.
Conclusions: While both crystalloid solutions appear safe and effective for fluid therapy in cats with urethral obstruction, the use of a balanced electrolyte solution may allow more rapid correction of blood acid–base status within the first 12 hours of fluid therapy. The use of a potassium-containing balanced electrolyte solution does not appear to affect the rate of normalization of blood potassium in treated cats with urethral obstruction.     

HIP DYSPLASIA: A FELINE POPULATION STUDY

The study population consisted of cats presented to the University of Missouri-Columbia Veterinary Medical Teaching Hospital from January 1, 1991 through December 31, 1995. Ventrodorsal radiographs including the pelvic region were evaluated for radiographic evidence of hip dysplasia. Each radiograph was evaluated independently by three board-certified veterinary radiologists and a consensus normal of dysplastic evaluation was determined. There were 684 cats from 12 breeds. The data derived from this study indicate the frequency of feline hip dysplasia in this population to be about 6.6% (45/684) and that the incidence appears to be breed dependent. Also, the radiographic appearance of hip dysplasia in cats is different than in dogs. A shallow acetabulum with remodeling and proliferation involving the cranio-dorsal acetabular margin were the most common radiographic signs. Minimal remodeling of the femoral neck was seen.     

雄犬尿道插管技术

在兽医临床上,尿道插管术是常用的操作技术之一,用于冲洗膀胱与尿道,根治炎症;导流尿液,规避感染;提供尿道支撑,防止闭塞等。但雄犬因尿道解剖与生理的特殊性,插管比较困难。反复操作必然给犬带来很多痛苦,而且容易损伤尿道黏膜,出现并发症。现有资料对雄犬尿道插管技术的介绍并不多见。笔者在研究雄犬尿道解剖结构与生理特点的基础上,结合临床实践经验,总结了雄犬尿道插管的实际操作技术,并详细分析了插管过程、导尿管留置期间和更换导尿管时应注意的问题及处理方法,以期为临床上科学地应用导尿管及开展泌尿外科动物试验提供一些帮助。