Abstract
Urine analysis in neonates requires invasive or skin-abrasive techniques for urine
collection. We determined validity of the measurements of some urine biomarkers when
urine was squeezed from cotton balls, and if urine samples could be collected in cotton
balls in neonates. 1) Urine was collected in volunteer subjects, divided into aliquots
of 5 mL fresh urine samples and 5 mL urine samples squeezed from cotton balls. Urine
ionogram, albumin, beta-2-microglobulin, and proteins were measured in both samples.
Imprecision was measured and compared to the relative variation of the biomarker results
measured with both urine collection techniques. Bland and Altman graphs were performed.
2) Cotton balls were used to collect urine samples in neonates to test if this collection
technique was feasible. Results: 60 subjects were included, 30 volunteer subjects
and 30 neonates. Collecting urine in cotton balls did not significantly bias the results
of sodium, potassium, chloride, glucose, urea, and creatinine. Proteins concentrations
were higher in fresh urine, and calcium results were altered by the interference of
calcium hypochlorite used to whiten purified cotton. Biomarkers could be measured
in 90% neonates with cotton balls. Collecting urine in cotton balls allows measurements
of sodium, potassium, chloride, glucose, urea, and creatinine in neonates without
damaging their skin.
Keywords
Neonate - cotton balls - urine - technique validation - urine bag
