Concentrations of unconjugated
pteridines (
neopterin,
monapterin,
biopterin,
pterin) were measured in the cerebrospinal fluid (CSF) of 310 patients, using a high performance liquid chromatography (HPCL) method. Our cohort included 209 controls (C), 15 patients with
meningism (M), 22 with
viral meningitis (VM), 17 with
bacterial meningitis (BM), 9 with
herpetic meningoencephalitis (HME), 2 with tuberculous
meningoencephalitis (TME) and 36 with peripheral systemic
infections (PI). These measurements, expressed as nmol/litre, showed a gradation of
neopterin concentrations according to the type of
infection: 20.1 + 6.5 in group C; 46.9 +/- 29.9 in group PI; 274.3 +/- 231.7 in group VM; 699.2 +/- 711.2 in group BM, 1,101.9 +/- 1,107.9 in group HME and 1,169 +/- 1,171.9 in group TME. There was no such gradation with
biopterin. Comparisons of means showed that total concentrations in the pathology groups were very different from those observed in controls and in the neuromeningeal
infections of the PI group. There was no correlation between the number of lymphocytes and the concentrations of
neopterin or
biopterin in the CSF. It is concluded that the concentration of
neopterin in the CSF is a sensitive but little specific marker of
infection, independent of CSF cellular reaction. Measuring this concentration makes it possible: 1) to evaluate the status of immune defences; 2) to predict that a
meningitis will become chronic, and 3) to detect a possible parenchymal participation in a meningeal
infection.