Case report: Skin protective barrier cream interference in benzethonium chloride method for urine protein measurement in a 6-month-old girl.

This case report describes the positive interference of the commonly used skin protective barrier cream used together with urine collection bags on the benzethonium chloride method for urine protein measurements in a 6-month-old female baby, leading to falsely elevated results. The interference was identified by both artificially mixing urine samples with this cream and comparing the results obtained using the benzethonium chloride method with those obtained using the pyrogallol red method.