To identify to what degree in-hospital delay of antibiotic therapy correlated to outcome in community acquired bacterial meningitis.

All cases of culture-positive cerebrospinal fluids in east Denmark from 2002 to 2004 were included. Medical records were collected retrospectively with 98.4% case completeness. Glasgow Outcome Scale was used. Multiple regression outcome analyses included the hypothesised factors: delay of therapy, age, bacterial aetiology, adjuvant steroid therapy, coma at admission and the presence of risk factors.

One hundred and eighty seven cases were included. Adult mortality was 33% and the proportion of unfavourable outcome in adults was 52%, which differed significantly from that of children (<18 years) with a mortality of 3% (OR=15.8, 95% confidence interval: 3.7–67.6) and an unfavourable outcome of 14% (OR=12.7, CI: 4.3–37.2). Delay of antibiotic therapy correlated independently to unfavourable outcome (OR=1.09/h, CI: 1.01–1.19) among the 125 adult cases. In the group of adults receiving adequate antibiotic therapy within 12h (n=109), the independent correlation between antibiotic delay and unfavourable outcome was even more prominent (OR=1.30/h, CI: 1.08–1.57). The median delay to the first dose of adequate antibiotics was 1h and 39min (1h and 14min in children vs. 2h in adults, p<0.01), and treatment delay exceeded 2h in 21–37% of the cases with clinically evident meningitis.

The delay in antibiotic therapy correlated independently to unfavourable outcome. The odds for unfavourable outcome may increase by up to 30% per hour of treatment delay.