Selvaraj Stephen

The Isolation and the Biofilm Formation of Uropathogens in the Patients with Catheter Associated Urinary Tract Infections (UTIs)

BACKGROUND Urinary tract infections are the most commonly acquired bacterial infections and they account for an estimated 25-40% of the nosocomial infections. The microbial biofilms pose a public health problem for the persons who require indwelling medical devices, as the microorganisms in the biofilms are difficult to treat with antimicrobial agents. AIMS The present study included the isolation and the biofilm formation of the uropathogens in patients with catheter associated urinary tract infections. METHODS AND MATERIALS This prospective analysis which was carried out over a period of two months, included 50 urine samples from catheterized patients with symptoms of UTI. Following their isolation and identification, all the isolates were subjected to the biofilm detection by the tube adherence method and the Congo Red agar method. RESULTS E.coli was found to be the most frequently isolated uropathogen 35(70%), followed by Klebsiella pneumoniae 8(16%), Pseudomona aeruginosa 2(4%), Acinetobacter spp 1(2%), coagulase negative Staphylococci 3(6%) and Enterococci spp 1(2%). In the current study, 30 (60%) strains were positive in vitro for the biofilm production. CONCLUSION To conclude, there was significant bacteriuria in all the symptomatic catheterized patients and E.coli was the most frequent isolate. Diabetes (44%) was the most common factor which was associated with the UTIs in the catheterized patients.

Changing Trends in Resistance Pattern of Methicillin Resistant Staphylococcus aureus

BACKGROUND Methicillin resistance in Staphylococcus aureus is associated with multidrug resistance, an aggressive course, increased mortality and morbidity in both community and health care facilities. Monitoring of newly emerging and prevalent Methicillin Resistant Staphylococcus aureus (MRSA) strains for their resistance patterns to conventional as well as novel drugs, are essential for infection control. AIMS To study the changing trends in resistance patterns of MRSA at our hospital. SETTINGS AND DESIGN This cross sectional study was carried out in a 750 bed tertiary care hospital in south India. MATERIAL AND METHODS One hundred and two clinical isolates of MRSA which were obtained in 2004-2011 were identified by using oxacillin, cefoxitin disc diffusion test and oxacillin screening agar test. Antibiotic susceptibility test was done for commonly used non beta lactam anti-Staphylococcal drugs, as well as for anti-MRSA drugs like vancomycin, linezolid, mupirocin and rifampicin. Minimum inhibitory concentration (MIC) of vancomycin was determined by using Vancomycin HiComb strip (Himedia, Mumbai, India). Statistical Analysis which was done: Chi-square test and proportions were used to compare the two groups. RESULTS MRSA isolates showed high resistance to co-trimoxazole (82.3%), ciprofloxacin (76.4%), gentamicin (64.7%) and tetracycline (49%) as compared to other drugs. High prevalence of ciprofloxacin resistance was detected, particularly among outpatients. Multi resistant MRSA with a ≥ 3 non-beta lactam agent resistance was 79%. All MRSA isolates were sensitive to vancomycin, linezolid, mupirocin and rifampicin. MRSA had displayed increase in resistance to most antibiotics except tetracycline in recent years. CONCLUSIONS Taking into consideration the prevalence of multidrug resistance in MRSA, resistance patterns should be evaluated periodically and antibiotic therapy should be guided by susceptibility testing.

Detection of extended spectrum beta lactamases, ampc beta lactamases and metallobetalactamases in clinical isolates of ceftazidime resistant Pseudomonas Aeruginosa

We studied the prevalence of ceftazidime resistance in Pseudomonas aeruginosa and the rates of extended-spectrum β-lactamase (ESBL), AmpC β-lactamase (AmpC) and metallo-β-lactamase (MBL) production among the ceftazidime resistant Pseudomonas aeruginosa. A very high rate of MBL production was observed, which suggested it to be an important contributing factor for ceftazidime resistance among Pseudomonas aeruginosa.

Bacteriophage types of methicillin-resistant Staphylococcus aureus in a tertiary care hospital.

BACKGROUND Phage typing had been utilised extensively to characterise methicillin-resistant Staphylococcus aureus (MRSA) outbreak strains in the past. It is an invaluable tool even today to monitor emergence and dissemination of MRSA strains. AIMS The aim of this study was to determine the prevalent phage types of MRSA in south India and the association between phage types, antibiotic resistance pattern and risk factors. METHOD A total of 48 non-duplicate MRSA strains recovered from various clinical samples during January to December, 2010 were tested against a panel of anti-staphylococcal antibiotics. Phage typing was carried out at the National Staphylococcal Phage Typing Centre, New Delhi. Out of 48, 32 hospitalised patients were followed up for risk factors and response to empirical and post sensitivity antibiotic therapy. The risk factors were compared with a control group of 30 patients with methicillin sensitive Staphylococcus aureus (MSSA) infection. RESULTS Amongst the five prevalent phage types, 42E was most common (52%), followed by a non-typable variant (22.9%), 42E/47/54/75 (16.6%), 42E/47 (6.2%) and 47 (2%). Phage type 42E was the predominant strain in all wards and OPDs except in the ICU where 42E/47/54/75 was most common. Although not statistically significant, strain 42E/47/54/75 (n=8) showed higher resistance to all drugs, except ciprofloxacin and amikacin, and were mostly D-test positive (87.5%) compared to the 42E strain (32%). Duration of hospital stay, intravenous catheterisation and breach in skin were the most significant risk factors for MRSA infection. CONCLUSION We found MRSA strain diversity in hospital wards with differences in their antibiotic susceptibility pattern. The findings may impact infection control and antibiotic policy significantly.

Neonatal sepsis and multiple skin abscess in a newborn with Down's syndrome: A case report

Neonatal sepsis is a leading cause of neonatal mortality. Congenital heart disease accounts for additional risk of sepsis in neonates. Here we report a case of Downs syndrome with late onset neonatal sepsis associated with multiple superficial skin abscesses simulating staphylococcal infection. The baby was empirically treated with vancomycin. Subsequently, multidrug resistant Klebsiella pneumoniae was detected from both pus and blood culture. Change to appropriate antibiotic resulted in clinical recovery. Although sepsis is one of the major ailments in neonates, atypical presentations of neonatal sepsis in Downs syndrome patients are underreported. Here we highlight the atypical presentation of Klebsiella sepsis and the importance of early antibiogram in such cases.

Chromobacterium violaceum: a potential nosocomial pathogen.

Chromobacterium violaceum is a motile gram-negative bacillus found as a saprophyte in soil and water.1,2 It is characterized by production of a purple pigment named violacein.2 It was first reported as a human pathogen in 1927 in Malaysia.1 Currently, it is recognized as a highly virulent opportunistic pathogen to humans, and several cases have been reported mostly from tropical and subtropical areas.1,2 Usual portal of entry of C violaceum is skin. The most common presentation in patients infected with C violaceum is sepsis, which is frequently life threatening.3 The other common manifestations include cutaneous involvement, followed by abscesses in liver, lungs, spleen, lymph nodes.1,3 Disseminated C violaceum infection has been reported to be associated with 60% to 80% mortality.1 C violaceum is frequently disregarded as a contaminant or misidentified. The awareness regarding this infection needs to be raised to a high degree because it is associated with high fatality rate.4 C violaceum has been commonly reported to be resistant to penicillins and cephalosporins. Therefore, in most cases of C violaceum infection, the initial empirical therapy based on penicillins and cephalosporins will not be effective and can result in increased mortality because of delay in initiation of appropriate therapy.1 However, it is usually susceptible to cotrimoxazole, fluoroquinolones, aminoglycosides, chloramphenicol, and carbapenems.1 C violaceum is able to survive under diverse environmental conditions because it produces several proteins contributing for its tolerance to antimicrobial compounds, heavy metals temperature, and acid.5 In our study, C violaceum was isolated 4 times from water samples collected under sterile precautions from operation theater taps of our hospital.Becausecontaminatedwater is thesourceof infectionandskin is the usual portal of entry of this organism, these isolates from the hospital environment can be a source of nosocomial infection.1,4 This can lead to fatal infection such as septicemia or deep abscess during preand postsurgical periods. Once infection is established, it should be diagnosed early, and prolonged antibiotic treatment is required.6 Regular surveillance of operation theater and critical care units for C violaceum in water samples is necessary to prevent mortality. Proper water treatment and safe water supply are also essential.