This is the first study to evaluate the susceptibility patterns of bacterial strains isolated from community acquired UTIs in Jaipur, Rajasthan. This study provides valuable laboratory data and allows comparison of the situation in Rajasthan with other parts of the country.
The results show that 17.19% of urine samples from patients attending the outpatient clinics at our hospital yielded significant pathogens. The culture positive rate for community acquired uropathogens was higher in our study than that reported at Aligarh, India (10.86%)(9
) and at Tehran, Iran (6.3%).(16
The demographic data indicates that women of the reproductive age group formed the main group of adult patients with UTI presenting to the outpatient clinics (42.34% of all UTI detected in women of age 21-50 years.) UTIs were reported in 62.42% of females and in 37.67% of males. It has been extensively reported that adult women have a higher prevalence of UTI than men, principally owing to anatomic and physical factors.(9
) Elderly (61 years or more) males had a higher incidence of UTI (49.23%) compared to the elderly females (21.75%). This is probably because with the advancing age, the incidence of UTI increases is men due to prostate enlargement and neurogenic bladder.(17
The study demonstrates that E. coli
remain the leading uropathogen being responsible for 61.84% of community acquired UTIs in our area, and no change in its prevalence among all community-acquired uropathogens was observed over the 2½ year study period. This is in consistence with findings of other studies around the globe in which E. coli
was the most frequently reported isolate from patients with community acquired UTIs.(7
) Following E. coli
, our study shows Enterococcus
species (9.24%) and Klebseilla species (6.64%) as the other common uropathogens in the community setting. Our findings are in accordance with a study by Dias Neto et al
) Enterobacteriaceae have several factors responsible for their attachment to the uroepithelium. These gram negative aerobic bacteria colonize the urogenital mucosa with adhesion, pili, fimbriae, and P1-blood group phenotype receptor.(17
) In our study, Enterobacteriaceae bacteria accounted for 76.87% of all the isolates, followed by gram positive cocci (14.16%) and non-fermenter gram negative bacteria (5.49%).
Our study reveals 23.83% of the E. coli
isolates and 8.69% of Klebsiella
species to be ESBL producers. Pitout et al
. have also highlighted the emergence of Enterobacteriaceae producing ESBLs in the community particularly from UTIs.(23
) Aggarwal et al
. reported 40% of E. coli
and 54.54% of Klebsiella
species to be ESBL producers from Rohtak, Haryana.(24
) In another study from Nagpur, 18.5% of E. coli
isolates and 25.6% of Klebsiella isolates were found to be ESBL producers.(25
) This geographical difference may be due to different patterns of antibiotic usage. Our study confirms the global trend towards increased resistance to β-lactam antibiotics. ESBL producing bacteria may not be detectable by routine disk diffusion susceptibility test, leading to inappropriate use of antibiotics and treatment failure. It is emphasized that institutions should employ appropriate tests for their detection and avoid indiscriminate use of third-generation cephalosporins.
Generally, uncomplicated UTIs are treated in the community with short courses of empirical antibiotics. In many cases, urine samples are only sent for microbiological evaluation following treatment failure, recurrent or relapsing infection. Although the levels of resistance we observed amongst community isolates may therefore overestimate the true rate of resistance in the community, the high levels of resistance of gram negative uropathogens to ampicillin, amoxiclav, and co-trimoxazole raise concerns over the use of these agents. Our findings are in consistence with the recent data reported from other developing countries.(26
) Our findings thus suggest that empirical treatment with these drugs should no longer be appropriate. The high antibiotic resistance against ampicillin and co-trimoxazole could be attributed to their wide usage for a variety of other indications.
Aminoglycosides (amikacin, gentamicin, and netilmicin) have also shown a decreasing resistance trend against E. coli from the year 2007 to 2009. Aminoglycosides being injectables are used restrictively in the community-care setting and hence have shown better sensitivity rates.
The overall resistance of E. coli to nalidixic acid, norfloxacin, and ciprofloxacin was 94.63%, 77.88%, and 74.75%, respectively. Fluoroquinolones have a wide variety of indications, permeate most body compartments, and are ubiquitously prescribed, accounting for the emergence of their resistance. Our findings indicate that urgent strategies to counteract increased resistance to these drugs must be developed or their use in uncomplicated infections should be strictly curtailed.
Nitrofurantoin has shown the least resistance for E. coil
. Our findings are similar to other Indian studies which have also demonstrated nitrofurantoin as an appropriate agent for first-line treatment of community acquired UTIs.(10
) Given the fact that Nitrofurantoin has no role in the treatment of other infections, it can be administered orally and is highly concentrated in urine; it may therefore be the most appropriate agent for empirical use in uncomplicated UTI. Fosfomycin is another oral antibiotic which is commonly used for treatment of CA-UTI in Europe with low resistance rates; however, it is not marketed in India.(11
Resistance to cefoperazone/sulbactam and piperacillin/tazobactam for Enterobacteriaceae was low probably reflecting their lower usage for treatment of community acquired infections. Vancomycin is the drug with least resistance to gram positive cocci. An overall 1.82% resistance for vancomycin was observed in gram positive cocci belonging to the Enterococcus species. Although, the frequency of isolation of vancomycin-resistant Enterococci is not very high in our setting as compared to West, this may just be the beginning of the problem.