Meningitis and detectable interferon-alpha. Diagnosis and treatment.

Background. - In meningitis without germs, the existence of an inflammatory syndrome leads toward a bacterial etiology while the detection of interfer on-alpha (IFN-alpha) in the cerebrospinal fluid (CSF) argues for a viral me ningitis. The coexistence of the inflammatory syndrome and the presence of IFN-alpha in the CSF makes this differentiation difficult. The reported cas e yields the picture and begs the question on the diagnostic approach and t he required therapeutic attitude. Case report. - A six-week-old infant, exclusively breast-fed, was hospitali zed for fever. The examination showed an important inflammatory syndrome an d meningeal attempt with a cellularity at 94/mm(3) with 53% polymorphonucle ar neutrophils, contrasting with normal proteinorrhachia and glycorrhachia. The IFN-alpha in the CSF was present at 4 Ul/mL while the bacteriological culture and the viral search by PCR were negative. The clinical and biologi cal worsening within the first 36 hours, in spite of the parenteral dispens ation of a triple antibiotic therapy (amoxicillin, ceftriaxone, netilmicin) , then a favorable clinical and biological response after adjunction of van comycin, led toward a pneumococcal meningitis with reduced sensitivity to b eta -lactams. The maternal antibiotic therapy by amoxicillin and its presen ce in the maternal milk favored the hypothesis of a decapitated bacterial m eningitis. Conclusion. - In the presence of a meningitis without germs, the coexistenc e of a sizable inflammatory syndrome and the detection of IFN-alpha in the CSF must be considered as an unusual phenomenon and motivate the pursuit of antibiotic therapy until viral identification. (C) 2000 Editions scientifi ques et medicales Elsevier SAS.