Antibiotic Resistance Pattern in Uropathogens at a Tertiary Care Hospital at Jhalawar with Special Reference To Esbl, AmpC b-Lactamase and Mrsa Production 645-651
Assistant Professor, Department of Microbiology,
Jhalawar Medical College and Hospital, Jhalawar,
Rajasthan, India - 326001.
Background: Urinary tract infections (UTIs) are one of the most common bacterial infections in humans, both in the community as well as in the hospital settings. Worldwide, the data show that there is an increasing resistance among the organisms which cause UTI, to the conventional drugs. A study on the changing antibiotic resistance pattern is pertinent for an appropriate treatment and for the prevention and control of the different mechanisms of resistance.
Aim: To find out the drug option for the treatment of UTI due to the presence of various clinical isolates in our geographical area, in the current scenario of increasing antimicrobial resistance, with special reference to ESBL, AmpC β-lactamase and MRSA production.
Materials and Methods: A total of 184 clinical isolates from the urine of various patients who presented to the outpatient and inpatient departments of Jhalawar Medical College and Hospital, Jhalawar, Rajasthan, India, were studied from January 2011 to September 2011. The antimicrobial susceptibility to various drugs was studied by the disc diffusion method, by following the CLSI guidelines. Confirmation of the extended spectrum β-lactamase (ESBL), ampC β-lactamase and methicillin resistant Staphylococcus aureus (MRSA) production was done by the phenotypic confirmatory disc diffusion test (PCDDT), the ampC disk test (ADT) and the oxacillin E test respectively.
Results: The antibiotic sensitivity pattern of the gram negative bacilli (GNB) revealed that the maximum sensitivity was seen for imipenem (95.1%), followed by cefoxitin (79.6%), piperacillin/ tazobactum (71.8%), cefepime (71.8%), and amikacin (66.9%), and that of the gram positive cocci (GPC) showed that the maximum sensitivity was seen for vancomycin and linezolid (100%), followed by amikacin (95.2%), gentamicin (69.1%) and nitrofurantoin (61.9%). High resistance was seen against amoxycillin/clavulanate, cotrimoxazole, cefotaxime, doxycycline and norfloxacin. Overall, the prevalence of ESBL and ampC β-lactamase and the coexistence of the phenotype (ESBL + ampC β-lactamase) and MRSA in the urinary isolates was found to be 66.9%, 21.1%, 3.5% and 42.4% respectively.
Conclusion: Among the oral drugs, amoxycillin/clavulanic acid, norfloxacin, doxycycline and co-trimoxazole should no longer be considered as the first line drugs for the empirical treatment of clinically evident UTI, because of the very high resistance rates. Nitrofurantoin can be used as an alternative drug only after the sensitivity testing. Parentral drugs such as aminoglycosides, carbapenams and piperacillin/tazobactum can be the alternative choice for complicated UTI. Also, control measures which include the judicious use of antibiotics, antibiotic cycling, the implementation of appropriate infection control measures and the formulation of an antibiotic policy must be done, to prevent the spread of these strains.