Neopterin concentrations in pediatric human immunodeficiency virus infection as predictor of disease activity.

Neopterin concentrations in 50 children with human immunodeficiency virus infection were correlated with disease course. The neopterin concentrations ranged from 4 to 70 nM with a mean of 34.7 +/- 25.1 (SD) nM compared with a mean of 6.1 +/- 1.6 nM in the human immunodeficiency virus-negative control group. Elevated neopterin concentrations above the upper range of the control group were detected as early as 5 months of age. Nineteen of 20 patients (95%) with neopterin concentrations above 20 nM either died or have severe clinical disease. Increasing neopterin concentrations were also associated with poor prognosis even though the first value was below 20 nM. Conversely neopterin concentrations less than 20 nM or declining concentrations were associated with a stable clinical course, except in terminal illness. With stepwise logistic regression analysis neopterin concentrations were predictive for disease progression. This predictive value was further improved by the addition of CD4 cell counts.