Serological relatedness among clinical and environmental Acinetobacter baumannii isolates isolated from hospitals in Baghdad

During 2011, 1900 clinical specimens (urine, wounds, burns, blood and sputum) and 240 hospital environment specimens were collected from four hospitals in Baghdad/Medical city including: Baghdad Teaching Hospital, The Martyr Gazi Al- Hariry Hospital, Welfare Teaching Hospital and The Burn Specialist Hospital. All specimens were cultured and 128 Acinetobacter baumannii were obtained from clinical and environmental specimens in a ratio of 6.05% (n=115) and 5.42% (n=13), respectively. These isolates were identified using microscopic examination, biochemical tests and Api 20 E system.The slide agglutination technique for rabbit immune sera and A. baumannii bacteria was used and our data analysis revealed a serological relatedness among the isolates. We found 22 different serotypes for 128 clinical and environmental A. baumannii isolates. The most common serotype was serotype 1 which included 34 isolates (26.56%) and there were 40 (31.25%) miscellaneous isolates which isolated from different specimens, departments and hospitals. Notably, they didn’t arrange within any of the 22 serotypes. Upon such findings we may conclude, there is a wide variation in serological characteristics of the locally isolated A. baumannii