Beta-2-microglobulin and ferritin in cerebrospinal fluid for evaluation ofpatients with meningitis of different etiologies

To determine whether or not the beta-2-microglobulin (beta 2-m) and/or ferr itin levels in cerebrospinal fluid (CSF) can be used as markers for the dif ferential diagnosis of meningitis and determination of the response to trea tment, 122, subjects with etiologically well-characterized diagnoses were c lassified into three groups: bacterial meningitis (n = 5; mean age +/- SD, 1.0 +/- 1.0 year), viral meningitis (n = 39; 5.9 +/- 3.8 years), and a non- meningitis group (n = 78: 5.2 +/- 4.9 years). The levels of beta 2-m and fe rritin in CSF were determined by means of a latex photometric immunoassay. The statistical significance of the data was analyzed with the Mann-Whitney U-test. A receiver operating characteristic curve was used to evaluate the diagnostic accuracy of each prediction marker. This study indicated that ( 1) the levels of beta 2-m and ferritin in CSF were related with age in the non-meningitis group: subjects of up to 5 months of age exhibited higher co ncentrations of these proteins than ones of above 6 months of age (beta 2-m , 1.89 +/- 1.13 vs. 0.84 +/- 0.65 mg/l, P < 0.01; ferritin, 2.97 +/- 2.04 v s. 1.81 +/- 1.34 mu g/l, P = 0.09); (2) the beta 2-m level was significantl y higher in the CSF of patients with viral meningitis than in ones without meningitis (2.41 +/- 1.23 vs. 0.84 +/- 0.65 mg/l, P < 0.01): the best cut-o ff value was 1.2 mg/l (3) the ferritin level was significantly higher in th e CSF of patients with bacterial meningitis than in ones with viral meningi tis (43.24 +/- 39.49 vs. 6.81 +/- 7.41 mu g/l, P < 0.01): the best cut-off value was 7.5 mu g/l; and (4) sequential measurement of the CSF ferritin le vel was of value for determination of the response to antibiotic treatment for bacterial meningitis. These results only apply to patients of greater t han 6 months of age. beta 2-m and ferritin in the CSF can be used as an anc illary tool for diagnostic guidance in the acute phase of meningitis and de termination of the response to treatment for bacterial meningitis. (C) 1999 Elsevier Science B.V. All rights reserved.