Objective: To determine the prevalence of macroalbuminuria and to describe the clinical and renal pathological changes associated with macroalbuminuria in a population of Canadian First Nation children and adolescents with type 2 diabetes.
Research design and methods: We conducted a retrospective chart review at a single tertiary care pediatric diabetes center, and a case series was constructed. We collected data on microalbuminuria (>or=3 mg/mmol creatinine [26.5 mg/g]) and macroalbuminuria (>or=28 mg/mmol creatinine [247.5 mg/g]), estimated glomerular filtration rate, renal pathology, and aggravating risk factors (poor glycemic control, obesity, hypertension, glomerular hyperfiltration, hypercholesterolemia, smoking, and exposure to diabetes in utero).
Results: We reviewed 90 charts of children and adolescents with type 2 diabetes. A total of 53% had at least one random urine albumin-to-creatinine ratio >or=3 mg/mmol (26.5 mg/g). There were 14 of 90 (16%) who had persistent macroalbuminuria at or within 8 years of diagnosis of diabetes. Of these 14 subjects, 1 had orthostatic albuminuria and 3 had spontaneous resolution of albuminuria. A total of 10 had renal biopsies performed. There were 9 of 10 who exhibited immune complex disease or glomerulosclerosis, and none had classic diabetic nephropathy.
Conclusions: This study suggests that the diagnosis of renal disease in children with type 2 diabetes cannot be reliably determined by clinical and laboratory findings alone. Renal biopsy is necessary for accurate diagnosis of renal disease in children and adolescents with type 2 diabetes and macroalbuminuria. The additional burden of nondiabetic kidney disease may explain the high rate of progression to end-stage kidney failure in this population.