Interleukin 6 May Be an Important Mediator of Trimethoprim-Induced Systemic Adverse Reaction Resembling Aseptic Meningitis

Moris and Garcia-Monco¹ recently presented an excellent review on drug-induced aseptic meningitis in the ARCHIVES. As they pointed out, the pathogenesis of the reaction is unknown. We have recently published a report on a series of 12 patients with a history of trimethoprim-induced systemic adverse reactions closely resembling aseptic meningitis.² Among that group, treatment with trimethoprim in vitro induced substantial interleukin 6 (IL-6) production, but no IL-1, tumor necrosis factor α (TNF-α), or IL-2 in the purified peripheral blood mononuclear cells. In support of those findings, we report a case of a trimethoprim-induced aseptic meningitis-like reaction, in which cytokines from blood and cerebrospinal fluid (CSF) were measured.