Clinicopathologic characteristics, pathology, and prognosis of 77 dogs with focal segmental glomerulosclerosis

Abstract

Background: Focal segmental glomerulosclerosis (FSGS) is a common cause of nonimmune complex glomerulopathy and the prognosis and clinicopathologic findings associated with this condition have not been described in dogs.

Objective: To characterize the presentation and identify clinical factors associated with the survival of dogs with FSGS.

Animals: Seventy-seven dogs diagnosed with FSGS based on evaluation of renal biopsy samples submitted to the International Veterinary Renal Pathology Service.

Methods: Retrospective review of medical records of dogs biopsied for evaluation of proteinuria between January 2015 and May 2017.

Results: The incidence of FSGS among all dogs biopsied for proteinuria was 26%. Significantly more females (48; 62.3%) than males (29; 37.7%) were affected (P = .04). At the time of biopsy, median serum creatinine concentration (SCr) was 1.2 mg/dL (range, 0.3-8.7), median serum albumin concentration (Alb) was 2.8 g/dL (range, 1.1-4.6), median systolic blood pressure was 153.5 mm Hg (range, 95-260), and median urine protein : creatinine ratio was 5.9 (range, 1.4-22). Median survival time after biopsy was 258 days (range, 26-1003) for dogs that died from all causes (n = 32). Factors that were associated with a shorter survival time included SCr ≥ 2.1 mg/dL (P < .01) and Alb < 2 g/dL (P < .01).

Conclusions and clinical importance: Most dogs with FSGS were female, and although commonly hypertensive, azotemia, severe hypoalbuminemia and ascites or edema were observed infrequently. Variables significantly associated with survival time were SCr and Alb.

Keywords: global glomerulosclerosis; glomerular disease; nonimmune complex glomerulopathy; podocyte; protein losing nephropathy; proteinuria; renal biopsy.

FIGURE 1

Kaplan‐Meier survival curve for serum creatinine in dogs with focal segmental glomerulosclerosis dying from all‐cause death. Median survival time post‐biopsy in dogs dying from all‐cause death was significantly shorter in dogs with serum creatinine ≥ 2.1 mg/dL (P < .001)

FIGURE 2

Kaplan‐Meier survival curve for serum albumin in dogs with focal segmental glomerulosclerosis dying from all‐cause death. Median survival time post‐biopsy in dogs dying from all‐cause death was significantly shorter in dogs with serum albumin < 2.0 g/dL (P = .03)