Frequency of extended spectrum beta-lactamases [ESBL] producing nosocomial isolates in a tertiary care Hospital in Rawalpindi

To find out the frequency of extended spectrum beta-lactamases [ESBL] producing organisms among Gram negative rods from clinical specimens. This was a descriptive study. The study was carried out in the Microbiology Department of Army Medical College, Rawalpindi from 1 Jan 03 to 31 Dec 03 on clinical samples received from admitted patients in Military hospital, Rawalpindi. It was carried out on clinical specimens of urine, blood, pus, catheter tips, fluids including CSF, sputum, chest tube, HVS and i/v canula/CVP line obtained from admitted patients in Military Hospital, Rawalpindi. The organisms were identified by standard techniques. Confirmation to the species level was done by API 20 E and API NE where required. Sensitivity testing was carried out by Modified Kirby Bauer disc diffusion method on Mueller Hinton agar incubated at 35o C in ambient air for 24 hrs. ESBL producing strains were identified by double disc diffusion method test according to Jarlier et al. Clavulanate was applied as the inhibitor of beta lactamases [AMO/CLAV disc]. The results were tabulated as frequencies. Forty three percent of clinical isolates yielded ESBL producing gram negative rods. Enterobacter cloacae [76%], Klebsiella oxytoca [68%] Acinetobacter baumanni, [63%] and Aeromonas hydrophila [50%] were the most frequent ESBL producing bacteria. Production of ESBL among Gram negative rods is frequent in Military Hospital, Rawalpindi. Infection control measures are required to control their spread

Changing frequencies and current status of multiple-drug resistant typhoidal salmonellae in year 2001-2003 at Rawalpindi

Typhoid fever is endemic in developing countries. Multiple drug resistant [MDR] typhoidal salmonellae are on the rise worldwide. We carried out a study in our setup to determine the changing frequencies of typhoidal salmonellae and to highlight their current antibiotic resistance patterns. The study was carried out on 15611 blood samples of admitted patients with febrile illness from 2001 to 2003. The blood culture samples were subcultured on Blood Agar and MacConkey Agar. Non lactose fermenting colonies were identified for typhoidal salmonellae and confirmed by using API 20E galleries and standard serological methods. Antibiotic susceptibility testing was performed using Modified Kirby-Bauer disk-diffusion method on Mueller-Hinton Agar. A total number of 333 isolates of Salmonella typhi and Salmonella paratyphi A were isolated from blood samples. Multidrug resistance was found in 172 [51.65%] isolates. The combined frequencies of MDR Salmonella typhi and MDR Salmonella paratyphi A decreased from 55.14% in year 2001 to 31.25% in year 2003 showing a decreasing trend. No Salmonella paratyphi B and Salmonella partyphi C were isolated in our study. None of the isolate was resistant to ciprofloxacin, ofloxacin and ceftriaxone. From 2001 to 2003, a changing trend in frequencies of MDR typhoidal Salmonella and reemergence of Salmonella typhi has been observed as compared to Salmonella paratyphi A. ciprofloxacin, ofloxacin and ceftriaxone are the drugs of choice for MDR typhoidal Salmonellae

Antibiotic resistance in campylobacter jejuni in Rawalpindi and Islamabad. A preliminary study

To determine the antimicrobial resistance in Campylobacter jejuni isolated from stools of children suffering from diarrhoea/dysentery in our setup against the antimicrobials commonly used as empirical therapy. Study: A prospective cross sectional descriptive study. Place and duration of study: Department of Microbiology, Army Medical College and Military Hospital, Rawalpindi from 29 August to 29 November 2002. Patients and methods: The study was carried out on eighteen isolates recovered from one hundred stool samples of children up to the age of twelve years admitted with diarrhoea/dysentery in Military hospital, Rawalpindi. The samples were collected in clean polypropylene containers containing Cary Blair medium. These were transported to the Microbiology Department, Army Medical College, Rawalpindi within 1-2 hours. The samples were inoculated on Modified Preston [Oxoid] and Karmali media [Oxoid] beside other routine stool culture media. The cultures were incubated at 42oC under microaerophilic conditions. The growth after 48 hours was provisionally identified by colonial morphology, oxidase test, Gram staining and motility. The organisms were identified to species level by hippurate hydrolysis, urease test, nitrate reduction, catalase test, H2S production, resistance to cephalothin and sensitivity to nalidixic acid. Sensitivity testing was carried by Modified Kirby Bauer disc diffusion technique on lysed horse Blood Agar against ampicillin [10 ug], erythromycin [15ug], tetracycline [10ug], chloramphenicol [30ug], trimethoprim/ sulphamethoxazole [1.25ug/23.75ug], nalidixic acid [30ug] and ciprofloxacin [5ug]. One isolate [7.14%] was resistant to ciprofloxacin, three [16.66%] to chloramphenicol and four [22.22%] to nalidixic acid, five [27.77%] to erythromycin, seven [38.88%] to tetracycline, sixteen [88.88%] to trimethoprim/sulphamethoxazole and ampicillin respectively. The susceptibility pattern reflects variable susceptibility with maximum resistance to ampicillin and trimethoprim/sulphamethoxazole. Four isolates were resistant to nalidixic acid