Product Information
Clinic Support
Client Information
Technical Information

Prevalence of Microalbuminuria in Dogs Evaluated at a Referral Veterinary Hospital

» View Only (Acrobat PDF)

SUMMARY:

• Microalbuminuria was present in ~30% of dogs seen at a referral veterinary teaching hospital (NCSU).

Microalbuminuria (MA) in humans is defined as urine albumin concentration (UAlb) between 20 and 200 µg/ml at normal diuresis. MA is a positive indicator for development of diabetic nephropathy in humans. MA also occurs with hypertension, neoplasia, cardiovascular disease, and in patients who are critically ill or have severe systemic infections. Recently, an ELISA has been validated for quantitation of canine UAlb. The purpose of this study was to determine the occurrence of MA in a random sampling of dogs evaluated at a referral veterinary hospital.

Urine samples were obtained from 67 dogs evaluated for a variety of clinical conditions. Dipstick urinalyses were performed on all samples; clinician discretion determined method of urine collection and performance of urine sediment examination and/or urine culture. Aliquots of urine were frozen (-80° C) within 15 minutes of collection. UAlb was quantified using an antigen capture ELISA. To account for varying urine concentrations, results were normalized to a specific gravity of 1.010.

UAlb in the study population ranged from 0.1 to >500 µg/ml (median 22.8, Q1 5.6, Q2 175.9). 32 dogs (48%) had negligible UAlb (<<20 µg/ml), 20 (30%) had MA (20-200), 15 (22%) had overt albuminuria (>200). When 21 dogs with hematuria (>5 RBC/hpf or >1+ via urine dipstick) and/or urinary tract infections were excluded, 27 of 46 dogs (59%) had negligible UAlb, 12 dogs (26%) had MA, and 7 dogs (15%) had overt albuminuria.

The 46 dogs without hematuria and/or urinary tract infections were categorized based on systemic disease. 3 (100%) dogs with cardiovascular disease, 2 (40%) dogs with urogenital disease, 4 (20%) dogs with neoplasia, and 3 (21%) dogs evaluated for other diseases had MA. 3 (60%) dogs with urogenital disease and 4 (20%) dogs with neoplasia had overt albuminuria. 4 (100%) of dogs without systemic illnesses had negligible UAlb.

This preliminary study shows that MA, defined as UAlb between 20 and 200 µg/ml, occurs in a high percentage of dogs evaluated at a referral veterinary hospital. The incidence of MA in all dogs is unknown because the minimum sensitivity of standard urine dipsticks is 200 to 300 µg/ml. Normal UAlb in dogs has not been established. Many of the diseases associated with MA in people are likewise associated with glomerular disease in dogs. Further studies are indicated to determine the range of UAlb in healthy dogs and in dogs with systemic disease, as well as the predictive value of MA for later onset of renal disease.

Reproduced with permission of the Journal of Veterinary Internal Medicine.