Metabolic profiles of urinary organic acids recovered from absorbent filter paper.

We evaluated for reliability and reproducibility a semiquantitative gas-chromatographic assay of organic acids in samples of normal urine recovered from absorbent filter paper. We also evaluated this method for use in diagnosis of some of the more common organic acidurias. Transfer of urine from diapers to absorbent filter paper eases the usual trauma of specimen collection from young children; it also simplifies sample storage and shipment.