Colistin resistant Acinetobacter baumanii in a tertiary care hospital of Pakistan: A retrospective single center study
Joint Event on 8th European Clinical Microbiology and Immunology Congress & 3rd World congress on Biotechnology
June 12-13, 2019 | Edinburgh, Scotland
Syed Bilal Tanvir, Ali Shariq and Hesham S Almoallim
Dar Al Uloom University Hospital, Saudi Arabia
Posters & Accepted Abstracts : Microbiol Curr Res
Statement of the Problem: Multidrug resistant (MDR)
A. baumannii is a prominent cause of hospital acquired
infection. It is a gram-negative Coccobacilli mostly
found in soil and is exclusively isolated from hospital
environment, but its natural habitat is still unknown. A.
baumannii is an opportunistic pathogen mostly infecting
immunocompromised patients. It can survive on inanimate
objects for a long period of time, therefore allowing it
to endure in the hospital environment. A surveillance
study conducted in the United States revealed that 10%
of patients admitted in intensive care unit acquired
pneumonia due to A. baumannii. The purposes of this study
were to determine the resistance pattern of A. baumannii
to colistin and carbapenem group of antibiotics in a tertiary
care hospital located in Karachi, Pakistan and compare it
with regional and international resistance pattern.
Methodology & Theoretical Orientation: A total of 705 clinical specimens over the period of July 2016 to June 2017 which included pus, wound swabs, ear swabs, eye swabs, urine, blood, tracheal aspirates and sputum samples were collected. All specimens (wound swabs, ear swabs, eye swabs, sputum, aspirates) were inoculated onto sheep blood agar, cultures were examined macroscopically for growth. Antimicrobial susceptibility was performed by Kirbauer disc diffusion techniques on muller hilton agar plate and standard disc zones were measured according to CLSI guideline. SPSS version 23 was used for statistical analysis. Prevalence and resistance pattern were deduced as well.
Results: A total of 705 clinical specimens were cultured and analyzed for antimicrobial resistance pattern. 61% of the isolates belonged to male patients, while 39% of the isolates belonged to female patients. The isolates were tested against amikacin, aztreonam, sulbactam/ cefperazone, ceftazadime, colistin, gentamicin, imipenem, meropenem, tigecycline and piperacillin/tazobactam. 57% and 74% of the isolates were resistant to amikacin and aztreonam respectively. While 60% and 69% of the isolates were resistant to sulbactam/cefperazone and ceftazadime respectively. A total of 14 (2%) isolates out of 705 clinical isolates were also found to be resistant to Colistin.
Conclusion: Acinetobacter baumanii isolates show a progressive trend of resistance to carbapenems and colistin. Hence judicious usage of carbapenems and colistin coupled with strict infection control protocols should be implemented. Susceptibility testing for colistin resistance should also be implemented in patients who have gone under treatment with colistin methansulfonate for severe infections.
Syed Bilal Tanvir holds an MD degree and a master’s in clinical microbiology from Queen Mary, University of London. He completed his postgraduate training in clinical microbiology at Barts and London School of Medicine and Dentistry and the Blizard Institiute. He is currently working in the position of a faculty member at Dar Al Uloom University Hospital, Riyadh, Saudi Arabia. He has previously presented his research in Jeddah, Karachi, Bahrain and London as well. His research interests include surveillance of antimicrobial resistance, systematic review and meta-analysis on newer antimicrobials and surveillance of gram-negative nosocomial infections.