Changing Etiology and Risk Factors of Nosocomial Bacterial Meningitis: a Nationwide Multicenter Study 1993-2010 in Slovakia

Background: Nosocomial meningitis is still associated with unrespectable high mortality and sequelae. The aim of this study was to assess if differences in etiology, risk factors and outcome of bacterial nosocomial meningitis (NM) between tree periods of survey (1993 - 1998, 1999 – 2006 and 2007 - 2010) in Slovakia. Methods: We performed multicentric observational study of nosocomial meningitis appearing in clinically hospital stay patients in 10 major hospitals (Bratislava, Trnava, Kosice, Ruzomberok, Nitra, Banska Bystrica, Nove Zamky, Presov, Zilina, Lucenec) in Slovakia. Two hundredand sixty-one patients diagnosed with NM, according to the criteria of the Centers for Disease Control and Prevention between 1993 and 2010 were evaluated retrospectively. Trends in risk factors and etiology of NM appearing 1993 – 1998, 1999- 2006 and 2007 – 2010 were compared. Differences between periods were assessed by univariate analysis. Chi-square test and Fisher's exact test computerized with the open source statistical package “R” were used and P < 0, 05 was considered statistical significant. Results: During 17 years, we have detected 261 cases with attributable mortality of 12,1% and sequellae in 19%. Comparing the three periods in our study of nosocomial meningitis in etiology staphylococci was decreasing (18,2% vs. 3,4%; P = 0,023) and gram-negative etiology was stable during all study period (52,7% vs. 41,6% vs. 55,9%; P = 0,876). Perinatal pathology or CNS abnormality, hydrocephalus as a complications and very low birth weight neonates significant decreasing between first and last period of study. Concerning risk factors craniocerebral trauma (7, 1% vs. 20%, P < 0,01) were more significant prevalent in late study period in comparison to the first study period. No significant change in mortality among tree periods of study (14.9% vs. 14.9% vs. 6,7%; P = NS), however there was a significant increase of neurologic sequellae or relapse, in 1993–1998 comparing 2007-2010 (17,8% vs. 33,3%; P = 0,02). Conclusion: Nosocomial bacterial meningitis is still frequent complications of trauma and surgery with 10–15% mortality rate. Gram-negative bacillary meningitis has become a important cause of hospital-associated central nervous system infection.