Trend, features and outcome of meningitis in the Communicable Diseases hospital, Alexandria, Egypt, 1997-2006

Background Following vaccine introduction, long-term epidemiological changes have been occurred in meningitis. Studying these changes is of practical importance for both public health planning and clinical management. Objectives To study trend in meningitis in Alexandria, Egypt (1997-2006) as well patients' characteristics and outcome. Materials and methods The descriptive epidemiologic approach was adopted. Study population was all discharge records and computer files of meningitis admissions to the Communicable Diseases Hospital in Alexandria, Egypt, 1997-2006. Outcome measures were age, number and percentage of patients, organisms proportions and case fatality. Results The study included 1210 recorded meningitis cases. Patients had a mean age of 22.26 years and a male to female ratio of 1.8 : 1. Study started with a sharp descent of yearly admissions (1997-1999) and ended by a sharp increase (2004-2006). Cases insignificantly increased during autumn through spring. Neisseria meningitidis was the dominant pathogen (28.9%) in all years. Mycobacterium tuberculosis (MTB) was the second common agent (11.6%) with a decreasing frequency till 2000. Streptococcus pneumoniae was responsible for 8.9% of cases. Group B Streptococci and Haemophilus influenzae type b caused 2.8% and 2.4% of cases respectively. Both had a declining trend. Other bacteria (gram negative bacteria, non specific streptococci and staphylococci) was isolated in 2.7% whereas no organism could be identified in 45.6% of specimens. All agent differences were statistically significant where P<0.001. The mean hospital stay was 14.95 days. Overall case fatality was 17.6%. The most lethal was other bacteria [Odds Ratio=6.0, 95% Confidence interval=3.0-12.2]. Fatal outcome was predicted by short hospital stay (regression coefficient(r)= -0.17, P<0.001), diagnosis of other bacterial (r=1.75, P<0.001), pneumococcal (r=0.66, P=0.02) or tuberculous meningitis (r=0.59, P=0.04) and being an elderly (r=1.80, P<0.001) or an adult (r=1.03, P<0.001). Conclusion Neisseria remained the main etiologic agent of meningitis. TB emerged as the second pathogen. Rate of bacterial un-detection was high. Mean age of meningitis had shifted to adult age. Other bacteria, pneumococci, MTB and advanced age were important predictors for mortality.