Characterization and Identification of Antibiotic-resistant Acinetobacter baumannii from Hospital Wastewaters

The present study was designed to characterize antibiotic-resistant Acinetobacter baumannii from some selected hospital environments in Benin City, Nigeria. A total of sixty (60) wastewater samples (15 samples from each hospital) were collected from hospital drains in University of Benin Teaching Hospital (UBTH); Health Centre (University of Benin); Central Hospital Benin and Faith Mediplex, Benin City between January and March 2014. Standard culture-based methods and biochemical approach were used for identification of the bacterial strains. Antimicrobial susceptibility profiles of the isolates were carried out using disc diffusion method. The mean cell density of heterotrophic bacteria ranged from 2.41xl06 ± 0.03 to 3.35xl07 ± 0.02 cfu/ml while the mean Acinetobacter species count ranged from 2.05x103 ± 0.01 to 7.55x104 ± 0.07 cfu/ml. Antibiotic-resistant profiles of the isolates revealed that 67/72 (93.06%) were resistant to amoxicillin (Penicillins), 62/72 (86.11%) were resistant to gentamycin (Aminoglycosides), 69/72 (95.83%) were resistant to ampiclox ([3-lactam/p-lactamase inhibitors); while 5/72 (6.94%) were sensitive to cefuroxime (Cephalosporin II) and chloramphenicol (Phenicols). Multidrug-resistant profile revealed that 33/72 (45%) of the isolates were resistant to PENR, GENR, APXR, AMXR, NALR, CHLR, PEFR, CXMR, TETR with multiple antibiotic-resistant index of 0.9. The findings from this study revealed A. baumannii in the hospital effluent were resistant to clinically relevant antibiotics. The multiple antibiotic-resistant index suggest a potential risk to public health and the surrounding communities.