Rapid Detection of Gram-Negative Bacterial Meningitis by the Limulus Lysate Test

Abstract

The limulus lysate test was evaluated as a tool for the rapid diagnosis of gram-negative bacterial meningitis in 112 patients. Positive assays were obtained on all initial cerebrospinal-fluid specimens from 38 patients with culture-proved gram-negative bacterial meningitis. Gram stain demonstrated organisms in 25 of these specimens. Negative limulus assays were obtained on all samples from 74 patients with gram-positive bacterial meningitis, tuberculous meningitis, aseptic meningitis or meningeal leukemia, as well as patients without meningitis. The limulus assay is a rapid, sensitive test for the diagnosis of untreated gram-negative bacterial meningitis, and may be useful for the detection of persistent bacterial growth or residual endotoxin in the absence of other spinal-fluid abnormalities. (N Engl J Med 289:931–934, 1973)