Acute Interstitial Nephritis (AIN) Risk Calculator
Use mg/dL. Approved range is 0.01 through 40.
mg/dL
Use mg/dL. The model derives the BUN:creatinine ratio internally.
mg/dL
Enter specific gravity as a decimal between 1.000 and 1.050.
unitless
Use a probability >0 and <=1. A value of 0.23 reproduces the development cohort and current MDCalc default.
probability
Clinical noticeEducational prebiopsy diagnostic-support tool only. Interpret alongside nephrology assessment, urinalysis context, and biopsy feasibility.
Context and use
AIN probability = logistic[(0.8367518 x ln(creatinine)) - (0.9181938 x ln(BUN/creatinine)) - (0.0501203 x ((specific gravity - 1) x 1000)) + (0.9360127 x proteinuria<2+) + 0.770398 + ln(local prevalence/0.23)]
The result is returned as a percentage rounded to one decimal place. Bands use the unrounded probability: <20% low, 20% to <50% intermediate, and >=50% high.
