Clinico –bacterialprofile of brain abscess in a tertiary care hospital

Anaerobic infection is usually polymicrobial in nature and has a significant role in mortality and morbidity of CNS infection. The bacteriology of Brain abscess is complex and consist of polymicrobialanerobic infections. We aimed to study the rate of isolation, poly microbial nature, association of predisposing factors and sensitivity pattern of obligate and facultative anaerobes in Brain abscess cases. This study was conducted in St Johns medical college, Bengaluru from January 2009 - June 2015.Total 30 samples were processed for the aerobic and anaerobic culture following the standard protocol. Out of 30 samples, 21 yielded the growth of pathogenic organisms. Obligate anaerobes were the major pathogens which were isolated from Brain abscess at the rate of 50% and Peptostreptococcus spp (10/26) was the most common obligate anaerobe other than Bacteroidesfragilis,Fusobacteriumspp, Prevotella spp etc. Chronic suppurativeotitis media was the common predisposing factor associated with Brain abscess other than congenital heart disease (CHD), Diabetes mellitus, sinusitis, etc. Polymicrobial synergism was most commonly associated with the obligate anaerobes contributing upto (46.6%) when compared to facultative anaerobes. Three pus aspirates yielded the growth of aseptatezygomycotic fungii and two cases having a fatal outcome of death. Antibiotic sensitivity of Bacteroidesfragilis showed intrinsic resistance for Penicillin and Microaerophilic streptococci showed intrinsic resistance to metronidazole. This study signifies about the polymicrobial obligate anaerobic infection in brain abscess and its association with the predisposing conditions like CSOM, sinusitis, CHD etc. Also it is important to look for the sensitivity pattern in complicated cases which helps in evidence based therapy. Hence this will results into better clinical outcome decreasing the morbidity and mortality associated with CNS infections.