Possible uses of urinary neopterin and biopterin measurement.

The measurement of urinary neopterin and biopterin may be an important non-specific diagnostic tool. Urinary biopterin has been found to be decreased in parkinsonian patients, and in hyperphenylalanemia as a variant of phenylketonuria. Urinary neopterin has been found to be elevated in numerous conditions. It has been shown to be significantly higher in AIDS patients than in ARC patients, and significantly higher in ARC patients than in controls. Urinary neopterin has been shown to be prognostically elevated in a wide range of neoplasias, including multiple myeloma, hematologic and gynecologic neoplasias. Neopterin is thought to be an in-vitro indicator of activation of the immune system.