Prevalence Assay of Antibiotic Resistance in Enterobacteriaceae Isolated from Hospital and Urban Wastewaters in Karaj City

Document Type : Research Paper


1 Former Graduate Student of Microbiology, Dept. of Microbiology, Karaj Branch, Islamic Azad University, Karaj, Iran

2 Assist. Prof., Dept. of Microbiology, Karaj Branch, Islamic Azad University, Karaj, Iran

3 Assist. Prof., Ecology and Environmental Pollution Control Research Group, Research Institute of Petroleum Industry, Tehran, Iran


Hospitals are hotspots for antimicrobial-resistant bacteria and will be expelled from hospitals via wastewater systems. In this study, we present ESBLs prevalence in Entrobacteriaceae strains isolated from hospitals and urban wastewaters in Karaj.A total of 100 Entrobacteriaceae strains were isolated from hospitals and urban wastewater in Alborz province during the summer of 2018. Bacterial strains were identified by standard microbiological and biochemical tests. The antimicrobial susceptibility test was determined according to Kirby Baur assay. ESBLs producers were screened by disc diffusion and combined disc and were studied by using specific primers for blaTEM and blaSHV genes. Among the organisms cultured, Escherichia coli (73%) was the most common organism followed by Klebsiella oxytoka (7%). Antibiotic resistance patterns were observed as follows: cefotaxim 26%, ceftriaxone 21%, ceftazidim 15% and cefepim 9%. Thirteen percent of isolates were detected as ESBLs producers. Based on the PCR results the frequency of blaTEM and blaSHV among the ESBLs producer isolates were 92.3% and 100% respectively. Antimicrobial resistance should now be seen as an environmental pollutant and new wastewater treatment processes must be assessed for their capability in eliminating antimicrobial-resistant bacteria, especially from hospital effluents.


Aali, R., Nikaeen, M., Hatamzadeh, M., Moazeni, M., Khanahmad, H. & Shahryari, A. 2016. The role of hospital wastewaters in dissemination of antibiotic resistant bacteria and resistance genes to the environment. Journal of Environmental Health Engineering, 3 (3), 239-248.
Canton, R., Novais, A., Valverde, A., Machado, E., Peixe, L., Baquero, F., et al. 2008. Prevalence and spread of extended-spectrum beta-lactamase-producing Enterobacteriaceae in Europe. Clinical Microbiology and Infections, 14, 144-153.
Chagas, T. P., Seki, L. M., Cury, J. C., Oliveira, J. A., Davila, A. M., Silva, D. M., et al. 2011. Multiresistance, beta-lactamase-encoding genes and bacterial diversity in hospital wastewater in Rio de Janeiro, Brazil. Journal of Applid Microbiology, 111 (3), 572-581.
Dzierzanowska, D., Kaminska, W., Semczuk, K., Borowiec, D., Matysiak, M., Szumala-Kakol, A., et al. 2010. Carriage of genes for various extended-spectrum beta-lactamases: a novel resistance strategy of Klebsiella pneumoniae in Poland. International Journal Antimicrobial Agents, 35, 392-395.
Empel, J., Baraniak, A., Literacka, E., Mrówka, A., Fiett, J., Sadowy, E., et al. 2008. Molecular survey of beta-lactamases conferring resistance to newer beta-lactams in Enterobacteriaceae isolates from Polish hospitals. Antimicrobial Agents Chemotherapy, 52 (7), 2449-2454.
Forbes, B. A., Sahm, D. F. & Weissfeld, A. S. 2007. Bailey and Scotts' Diagnostic microbiology, 12th Ed., St.Louis, Mosby.
Ghane, M. 2015. A survey of extended spectrum beta lactamase producing Enterobacteriaceae in hospital effluents. Medical Science Journal of Islamic Azad University, Tehran Medical Branch, 25(4), 283-288. (In Persian)
Haddadi, A. & Yeke Fallah, F. 2017. Frequency determination of blaTEM & blaSHV in the extended-spectrum beta-lactamase producing Escherichia coli isolates from Karaj. Iranian Journal of Medical Microbiology, 11, 75-80. (In Persian)
Karimi, S., Haddadi, A. & Torabzadeh, P. 2018. In vitro inhibitory effect of alcoholic and aqueous extract of Vaccinium Arctostaphylos on ESBLs producing klebsiella strains isolated from clinical specimens in Karaj. Journal of Arak University of Medical Sciences, 21(2), 75-85. (In Persian)
Korzeniewska, E., Korzeniewska, A. & Harnisz, M. 2013. Antibiotic resistant Escherichia coli in hospital and municipal sewage and their emission to the environment. Ecotoxicology Environmental Safety, 91, 96-102.
Lim, K. T., Yeo, C. C., Yasin, R. M., Balan, G. & Thong, K. L. 2009. Characterization of multidrug-resistant and extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strains from Malaysian hospitals. Journal of Medical Microbiology, 58 (11), 1463-1469.
Mansouri, S. & Abbasi, S. 2015. Prevalence of multiple drug resistant clinical isolates of extended-spectrum beta-lactamase producing enterobacteriaceae in Southeast Iran. Iranian Journal of Medical Sciences, 35(2), 101-108. (In Persian)
Nikoogoftar Ranjbar, S., Pourbabaee, A. A. & Davari, K. 2017. The frequency of antibiotic resistant coliforms isolated from sewage of Qom city, Iran. Qom University Medical Sciences Journal, 10(10), 69-77. (In Persian)
Prayitno, Kusuma, Z., Yanuwiadi, B. & Laksmono, R. W. 2013. Study of hospital wastewater characteristic in Malang city. International Journal of Engineering and Science,2(2), 13-16.
Shabani, L. N., Shayegh, J. & Sadeghi, J. 2018. Frequency of blatem, blashv, and blactx-m genes encoded extended-spectrum beta-lactamases in escherichia coli isolates collected from groundwater in east Azerbaijan province in 2014. Medical Journal of Tabriz University of Medical Sciences,40(2), 58-63. (In Persian)
Shakibaie, M. R., Jalilzadeh, K. A. & Yamakanamardi, S. M. 2009. Horizontal transfer of antibiotic resistance genes among gram negative bacteria in sewage and lake water and influence of some physico-chemical parameters of water on conjugation process. Journal of Environmental Biology, 30(1), 45-49.
Takdastan, A., Kordestani, B., Neisi, A. & Jalilzadeh Yangejeh, R. 2017. Determination of biokinetic coefficients for the extended aeration activated sludge system treating hospital effluents in hot climate conditions. Journal of Water and Wastewater, 28(2), 97-103. (In Persian)
Wayne, P. A. 2008. Performance standards for antimicrobial susceptibility testing. 18th Informational Supplement M100-S18, Clinical and Laboratory Standards Institue, Philadephia, 120-126.
Weldhagen, G. F., Poirel, L. & Nordmann, P. 2003. Ambler class a extended-spectrum beta-lactamases in Pseudomonas aeruginosa: novel developments and clinical impact. Antimicrobial Agents and Chemotherapy, 47(8), 2385-2392.
Yang, C. M., Lin, M. F., Liao, P. C., Yeh, H. W., Chang, B. V., Tang, T. K., et al. 2009. Comparison of antimicrobial resistance patterns between clinical and sewage isolates in a regional hospital in Taiwan. Letters in Applied Microbiology, 48(5), 560-565.