Emerging Infectious Diseases

Acinetobacter baumannii is now a formidable emerging pathogen. It is being increasingly isolated in clinical settings and from a wide range of infections. It is known that A. baumannii shows presence of dormant cells, a characteristic feature rarely found in other gram negative bacteria. This explains its environmental persistence as well as its ability to survive for a long time on abiotic surfaces under desiccated conditions. This ability to colonise and to grow as a biofilm has an important role in its persistence and spread in hospital environment. But whether the level or strength of biofilm formation varies with infection of different organs is not yet known. If an association can be found out between strength of biofilm formation and its variation according to different sites of infection, it can give a clue that pathogenesis of biofilm formation may have an intimate link with organotropism of different isolates. Multiple isolates of A. baumannii were taken from different clinical materials. Biofilm forming reference strains of A. baumannii (ATCC19606) and non biofilm forming reference strains of E. coli (ATCC25922) were used as positive and negative controls respectively. The strength of biofilm forming capacity (high/ medium/none) of each isolate was measured by microtitre plate method with primary filter of ELISA plate reader set at 570 nm. It was found that strength of biofilm formation varied for different sources of infection. The present study was a hospital based observational cross sectional study.