Isolation of bacteriophages to multi-drug resistant Enterococci obtained from diabetic foot: A novel antimicrobial agent waiting in the shelf.

Introduction: While foot infections in persons with diabetes are initially treated empirically, therapy directed at known causative organisms may improve the outcome. Many studies have reported on the bacteriology of diabetic foot infections (DFIs), but the results have varied and have often been contradictory. The purpose of the research work is to call attention to a frightening twist in the antibiotic-resistant Enterococci problem in diabetic foot that has not received adequate attention from the medical fraternity and also the pharmaceutical pipeline for new antibiotics is drying up. Materials and Methods: Adult diabetic patients admitted for lower extremity infections from July 2008 to December 2009 in the medical wards and intensive care unit of medical teaching hospitals were included in the study. The extent of the lower extremity infection on admission was assessed based on Wagner's classification from grades I to V. Specimens were collected from the lesions upon admission prior to the initiation of antibiotic therapy or within the first 48 h of admission. Results: During the 18-month prospective study, 32 strains of Enterococcus spp. (26 Enterococcus faecalis and 06 E. faecium) were recovered. Antibiotic sensitivity testing was done by Kirby-Bauer's disk diffusion method. Isolates were screened for high-level aminoglycoside resistance (HLAR). A total of 65.6% of Enterococcus species showed HLAR. Multidrug resistance and concomitant resistance of HLAR strains to other antibiotics were quite high. None of the Enterococcus species was resistant to vancomycin. Conclusion: Multidrug-resistant Enterococci are a real problem and continuous surveillance is necessary. Today, resistance has rendered most of the original antibiotics obsolete for many infections, mandating the development of alternative anti-infection modalities. One of such alternatives stemming up from an old idea is the bacteriophage therapy. In the present study, we could able to demonstrate the viable phages against MDR E. faecalis.

Magnitude of drug resistant shigellosis: A report from Bangalore.

Shigella is an important cause of acute invasive diarrhea in children and others. Antimicrobial susceptibility of Shigella spp. isolated from diarrhoeal/ dysenteric patients in Bangalore was studied in our hospital from January 2002 to December 2007. One hundred and thirty-four isolates were identified as Shigella species. S. flexneri, S. sonnei , S. boydii and S. dysenteriae were accounted respectively for 64.9%, 21.6%, 8.2% and 3.7% of the total number of Shigella isolated. Of these 56 (41.8%) were from children (0 to 14 years) and 78 (58.2%) were from adults and elderly patients. Over 70% of Shigella isolates were resistant to two or more drugs including Ampicillin and Co-trimoxazole. During 2002 to 2007, resistance to Ampicillin had increased from 46.7% to 68%. For Co-trimoxazole, though the resistance had gradually decreased from 100% to 72%, but still the resistance is high. Chloramphenicol resistance showed sudden decline from 73.3% to 25% from 2002 to 2003, but gradually has reached 48%. Nalidixic acid resistance was more than 70%. All isolates were sensitive to Ciprofloxacin during the period 2002 to 2004, but over the years the resistance pattern gradually increased up to 48%. Ceftriaxone had shown no resistance. The results of the study revealed the endemicity of Shigellosis with S. flexneri as the predominant serogroup. Children were at a higher risk of severe shigellosis. The results also suggest that Ampicillin, Co-trimoxazole, Chloramphenicol, Nalidixic acid and Ciprofloxacin should not be used empirically as the first line drugs in the treatment of Shigellosis. Periodic analysis and reporting of antibiotic susceptibility is an important measure to guide antibiotic treatment.

Direct drug susceptibility testing of Mycobacterium tuberculosis to primary anti-tubercular drugs by nitrate reductase assay.

Objectives: Traditional drug susceptibility testing for Mycobacterium tuberculosis takes weeks and/or expensive. In this study, we evaluated nitrate reductase assay for drug susceptibility testing which is faster than the visual detection of colonies. Materials and Methods: 32 clinical specimens (direct microscopy positive for AFB with 1+, 2+ or 3+ grading) were decontaminated and the sediment was inoculated onto the L-J medium with INH or Rifampicin incorporated with Potassium nitrate and the same medium without antibiotics at 1;10 dilution as control. After 2 weeks, the control was first tested for color change with addition of nitrate reductase reagents. If found positive, the media with antibiotics were tested and compared. Futher incubation was done if the control was found to be negative. The results obtained was compared with standard direct proportion method for drug susceptibility testing. Results: Resistance of isolates as shown by both methods for INH and Rifampicin was 37.5% and 31.3% respectively. The results showed that NRA and proportion method do not differ significantly ( P < 0.05 for both drugs). Thus an excellent agreement between the results of NRA and proportion method was found for two primary anti-tubercular drugs, 87.5% for INH and 97% for Rifampicin. Conclusion: Nitrate reductase assay is a rapid and inexpensive method for susceptibility testing of M. tuberculosis for primary anti-tubercular drugs and could be an alternative to existing methods, particularly in resource poor settings.

Antibiotic resistance profile & extended spectrum beta-lactamase (ESBL) production in Acinetobacter species.

BACKGROUND & OBJECTIVES: Members of the genus Acinetobacter are an important cause of nosocomial infections and with widespread resistance to various antibiotics. Extended spectrum beta lactamase (ESBL) associated resistance among Acinetobacter species is now known. The aim of this study was to speciate clinical isolates of Acinetobacter, analyze their resistance patterns, identify the production ESBLs and compare the role of different cephalosporins in detecting ESBL production in the isolates. METHODS: One hundred and fifty clinical isolates of Acinetobacter were speciated by various phenotypic tests. Antibiotic susceptibility was determined by the standard disc diffusion method. ESBL production was detected by the double disk approximation test using clavulanate containing disk and four different cephalosporin disks. Results of the above test were confirmed using the NCCLS phenotypic confirmatory test for ESBLs on a limited number of isolates. RESULTS: Most of the isolates were of respiratory origin. A. calcoaceticus A. baumannii (Acb) complex was the predominant species isolated (75%). Most isolates were resistant to the antibiotics tested including the third generation cephalosporins. Most isolates were sensitive to carbapenems and cefoperazone-sulbactam. ESBL production was detected in 28 per cent of the isolates. In the double disc approximation test, cefepime and cefotaxime could detect most of the ESBLs in Acinetobacter isolates. INTERPRETATION & CONCLUSION: A high level of antibiotic resistance was found in Acinetobacter in our study. Acb complex was the predominant and the more resistant species. Relatively high levels (28%) of ESBL have been detected in Acinetobacter and may reflect the scenario in India. ESBL production in Acinetobacter should be promptly detected and reported as it helps in treating individual cases and also in controlling the spread of these resistant phenotypes to other individuals.

Mechanisms of resistance to carbapenems in meropenem- resistant Acinetobacter isolates from clinical samples.

PURPOSE: To analyze the resistance mechanisms in Acinetobacter species by phenotypic methods. METHODS: Antibiotic susceptibility profile for 150 clinical isolates of Acinetobacte r was determined by the standard disk diffusion method. Isolates detected to be meropenem resistant were tested further by broth microdilution minimum inhibitory concentration (MIC) for meropenem. The resistant isolates were also tested for metallo beta -lactamase (MBL) production by the double-disk approximation test, for AmpC beta-lactamase production and efflux pump detection by agar microdilution MIC with and without reserpine. RESULTS: Twenty-one isolates were found resistant to meropenem by the standard disk diffusion method. Nine samples were from patients admitted in intensive care units (ICUs). Broth microdilution MICs of the isolates revealed low-level resistance to meropenem. MBL was not produced by any of these isolates. AmpC beta -lactamases were produced by nine (43%) isolates. 'Efflux pump'-mediated resistance to meropenem was detected in two out of nine random isolates tested for the same. CONCLUSIONS: Carbapenem resistance is not uncommon in Acinetobacter isolates. AmpC production may cause carbapenem resistance. MBL and efflux pump may not be important causes of carbapenem resistance.

Occurrence and characterisation of uropathogenic Escherichia coli in urinary tract infections.

PURPOSE: To study the occurrence of Uropathogenic Escherichia coli (UPEC) in cases with urinary tract infections. METHODS: A total of 220 cases from urinary tract infections and 50 stool samples from apparently healthy individuals were included. The colonies identified as Escherichia coli were screened for virulence factors namely haemolysin, Mannose Resistant and Mannose Sensitive Haemagglutination (MRHA, MSHA), Cell surface hydrophobicity and Serum resistance by recommended methods. RESULTS: Among 220 cases 91(41.36%) were haemolytic, 68(30.9%) showed MRHA, 58(26.36%) were cell surface hydrophobicity positive and 72(32.72%) were serum resistant. In 50 controls 3(6%) were haemolytic, 6(12%) showed MRHA, 9(18%) showed cell surface hydrophobicity and 12(24%) were serum resistant. The difference between cases and controls for haemolysis and MRHA were significant (p< 0.001 and p< 0.01 respectively). A total of 14 atypical Escherichia coli were isolated from urine and all showed the presence of one or the other virulence markers.Out of 18 mucoid Escherichia coli isolated 10 were serum resistant. Interestingly among the 15 Escherichia coli isolated from patients with pyelonephritis 8 were UPEC. CONCLUSIONS: Out of 220 urinary isolates, 151 could be labelled as UPEC.

A hospital based study of hepatitis E by serology.

Hepatitis E virus is recently recognised as an important cause of non-A, non-B hepatitis. A total of 569 serum samples were screened for HEV between April 1997 and March 2000, by a commercially available HEV IgM capture ELISA. The diagnosis was invariably acute viral hepatitis for differential diagnosis of jaundice. The percentage of seropositivity was found to be 18.8% in confirmed Hepatitis E cases.

Human ocular dirofilariasis in Kerala Southern India.

A twenty-six year old female presented to the Ophthalmology OPD with swelling of the upper eyelid. On excision, two long, thin, dead worms were removed. Microscopic and HPE showed the worms to belong to the Dirofilaria species.

A high incidence of ciprofloxacin resistance in urinary isolates in eastern Nepal.

A study was conducted to examine the incidence of ciprofloxacin resistance in the strains of bacteria isolated from patients with suspected urinary tract infection (UTI) and to analyse the level of resistance. A total of 63 bacterial isolates were grown from quantitative urine culture and were in significant count. Antibiotic susceptibility tests were done by using disc diffusion method of Kirby-Bauer and the level of resistance was analyzed by break point minimum inhibitory concentration (MIC). Majority of bacteria isolated and tested were Gram negative with Escherichia coli as the commonest isolate. Antibiotic susceptibility testing revealed a high prevalence of resistance to nalidixic acid, ampicillin and norfloxacin.

Urinary IgG antibody capture particles adherence test for detecting HIV antibodies: a preliminary report.

It is known that antibodies to HIV are secreted in urine and saliva. IgG antibody capture particle adherence test (GACPAT) has been shown to provide accurate results for antibodies in urine. The aim of the study was to study the sensitivity and specificity of this test in our settings. 114 urine samples were collected from both HIV positive and HIV negative patients and were analysed using GACPAT. The test has a sensitivity of 92.3% and specificity of 100%. We feel that this test has a definite role in our country especially for surveillance purposes.