WASHINGTON — Less than half of patients with bacterial meningitis have the classic symptom triad of fever, stiff neck, and a change in mental status, Diederick van de Beek, M.D., said while presenting a poster at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.
Dr. van de Beek, a neurologist at the Academic Medical Center in Amsterdam, reported that many patients present with just two classic symptoms, one of which may also be headache.
Infection with Streptococcus pneumoniae is such a powerful predictor of poor outcome that it should also be a factor when physicians decide whether to do a lumbar puncture. Patients who only have a lower level of consciousness and infection with S. pneumoniae should also be assessed for bacterial meningitis by lumbar puncture, he told this newspaper.
In a review of 696 patients with community-acquired, acute bacterial meningitis, the classic symptom triad occurred in 44% of patients, Dr. van de Beek reported in his poster. (The data have been published: N. Engl. J. Med. 2004;351:1849–59).
In contrast, 95% of patients had at least two classic symptoms. The most common classic symptom was headache in 87%, followed by neck stiffness in 83%, fever in 77%, and a change in mental status in 69% (defined as a Glasgow Coma Scale score of less than 14).
Of these patients, 21% died and 13% had other unfavorable outcomes including a vegetative state or severe or moderate disability. The likelihood that a patient would have an unfavorable outcome was sixfold higher among patients who were infected with S. pneumoniae than among those infected with Neisseria meningitides when the incidence rates were adjusted for potential clinical confounders.
This study is the first report of a prospective, large-scale analysis of the clinical factors associated with bacterial meningitis and its outcomes, Dr. van de Beek said at the conference, sponsored by the American Society for Microbiology. The study data were drawn from information on all patients who were at least 16 years old and diagnosed with bacterial meningitis in the Netherlands Reference Laboratory database from October 1998 through April 2002.
Of 1,108 cases in the database, complete data were retrieved for 754 patients, of whom 58 were excluded either because their infection was nosocomial, they had had recent neurosurgery, or they had received a neurosurgical device.