Management of Microalbuminuria in Pediatric Patients

Definitions and Diagnostic Criteria

Microalbuminuria is defined as urinary albumin excretion of 30-299 mg/24h, 30-299 mg/g creatinine on a random spot urine sample, or 20-199 μg/min on a timed collection, according to the American Diabetes Association 1
Albuminuria (macroalbuminuria) refers to higher levels of albumin excretion that exceed these thresholds, indicating more advanced kidney damage, as stated by the American Diabetes Association 2, 1
Confirmation of microalbuminuria requires 2 out of 3 abnormal specimens collected within a 3-6 month period due to day-to-day variability, as recommended by the American Diabetes Association 2, 3, 1
First morning void samples are preferred to minimize effects of orthostatic proteinuria, which is common in adolescents, according to the American Academy of Pediatrics 4, 1

For children with type 1 diabetes, the American Diabetes Association recommends annual screening should begin once the child is 10 years of age and has had diabetes for 5 years 2, 3
For children with type 2 diabetes, screening should begin at the time of diagnosis and be repeated annually, as recommended by the American Academy of Pediatrics 5, 4
Screening is performed with a random spot urine sample analyzed for microalbumin-to-creatinine ratio, according to the American Diabetes Association 2, 3

Microalbuminuria is an early marker of diabetic nephropathy and predicts progression to gross proteinuria within 6-14 years, as stated by the American Diabetes Association 2, 1
Risk factors for nephropathy include poor glycemic control, smoking, family history of hypertension or cardiovascular disease, and hypertension, according to the American Heart Association 2, 6
Higher rates of microalbuminuria have been reported among youth with type 2 diabetes than in their peers with type 1 diabetes, as found by the American Academy of Pediatrics 5, 4

Confirmed, persistently elevated microalbumin levels should be treated with an ACE inhibitor titrated to normalization of microalbumin excretion, even if blood pressure is not elevated, as recommended by the American Academy of Pediatrics 2, 5, 4, 1
Monitor microalbumin excretion every 3-6 months to assess response to therapy and disease progression, according to the American Academy of Pediatrics 4, 1

Rule out non-diabetes-related causes of renal disease before confirming diabetic nephropathy, as recommended by the American Academy of Pediatrics 5, 4
Orthostatic proteinuria is common in adolescents and usually benign; confirm with first morning void, according to the American Academy of Pediatrics 4
ACE inhibitors and ARBs are contraindicated in pregnancy, as stated by the American College of Obstetricians and Gynecologists 1