Biofilm formation by clinically isolated Staphylococcus Aureus from India.

INTRODUCTION: Staphylococcal biofilms are prominent cause for acute and chronic infection both in hospital and community settings across the world. Current study explores biofilm formation by Staphylococcus aureus isolates from clinical samples by different methods. METHODOLOGY: Standard techniques used for the characterization of S.aureus. Qualitative and quantitative biofilm formation was assessed by Congo red Agar, Tube and Microtiter plate methods. RESULTS: A total of 188 clinical isolates of S.aureus were screened for biofilm formation and 72 (38.29%) of them were found to be biofilm producers, 34 (18.08%) strong, 38 (20.21%) moderate. The remaining 116 (61.7%) were weak/ non biofilm producers. Maximum biofilm formers were recorded in pus samples (39.06%), followed by isolates from blood (38.23%) and urine (34.61%). Statistical analysis for the formation of biofilm indicated that Microtiter plate method is the most sensitive and specific method for screening biofilm production. CONCLUSIONS: Biofilm formation is one of the influential virulence factor in staphylococcal pathogenesis and persistence. Microtiter plate and Congo red agar remain as reliable methods for the qualitative and quantitative estimation of biofilm formation. Monitoring of biofilm formation in various etiological agents will help in determining the severity of infection.

Antibiotic resistance patterns of Staphylococcus aureus: A multi center study from India.

Chemotherapy and emergence of drug resistance strains of Staphylococcus aureus is receiving serious threats, due to the origin and spread of hospital and community acquired MDR strains. The present study reports the prevalence of antibiotic resistance among Staphylococcus aureus isolated from clinical samples from different cities of India. Antibiotic sensitivity was performed by Kirby-Bauer disk diffusion method and minimum inhibitory concentrations were determined for vancomycin and methicillin according to CLSI (2014) guidelines. A total of 212 S. aureus were obtained from different samples such as pus, blood, urine. The antibiogram of these isolates indicated widespread resistance to various groups of antibiotics ranging from a minimum of 10.13% against Phenicols (Chloramphenicol) to a maximum of 97% against Penicillin and 44.8% isolates were MRSA and alarmingly 10.84% were VRSA. Most of the MRSA isolates showed inducible Clindamycin resistance. Widespread prevalence of MDR patterns, increasing incidence of MRSA and VRSA calls for exploration of alternative medicines and new approaches to combat Staphylococcal infections.

Antibiotic Susceptibility Pattern of ESßL Producing Klebsiella pneumoniae Isolated from Urine Samples of Pregnant Women in Karnataka.

BACKGROUND: Klebsiella pneumoniae possess a new problem to health care professionals worldwide, which complicates and limits therapeutic options. It is one of the leading nosocomial bacterial pathogens, and the present study aims to determine the prevalence of ESßL producing K. pneumoniae isolates with their antibiotic susceptibility pattern in urine samples of the pregnant women with UTI. MATERIALS AND METHODS: Using standard isolation and identification procedures a total of 41 isolates were obtained from 417 midstream urine samples of pregnant women with suspected UTI in Karnataka. The antibiotic resistance profile of each isolate was performed by Kirby-Bauer disc diffusion method and ESßL production by standard phenotypic method. RESULTS: Isolation rate of K. pneumoniae in pregnant women was 19.9% and overall incidence rate was 9.8%. Among the 41 K. pneumoniae isolates, 26 (63.4%) were ESßL producers and all were found to be Multi Drug Resistance (MDR). The antibiotic susceptibility test (AST) for the isolates revealed that the highest number of K. pneumoniae were resistant to ampicillin (75.6%) followed by, nitrofurontoin and cefuroxime (73.1%) and least to chloramphenicol (12.1%). ESßL producers were highly resistance to nitrofurontoin (69.2%) and cotrimonazole (65.2%) and lower resistance was (7.6%) to amaikacin, observed. A higher resistance pattern to these two antibiotics was observed against ESßL non producing K. pneumonia but lowest to polymyxin B (13.3%) instead of amikacin (26.6%). All the isolates were found to be susceptible to imipenem. CONCLUSION: Present investigation revealed high prevalence of MDR- ESßL producing Klebsiella pneumoniae, which indicates dire need for effective ESßL surveillance in the community by using cost effective antimicrobials agents.

Isolation and characterization of Paracoccus sp. GSM2 capable of degrading textile azo dye Reactive Violet 5.

A potential bacterial strain GSM2, capable of degrading an azo dye Reactive Violet 5 as a sole source of carbon, was isolated from textile mill effluent from Solapur, India. The 16S rDNA sequence and phenotypic characteristics indicated an isolated organism as Paracoccus sp. GSM2. This strain exhibited complete decolorization of Reactive Violet 5 (100 mg/L) within 16 h, while maximally it could decolorize 800 mg/L of dye within 38 h with 73% decolorization under static condition. For color removal, the most suitable pH and temperature were pH 6.0-9.0 and 25-40 °C, respectively. The isolate was able to decolorize more than 70% of five structurally different azo dyes within 38 h. The isolate is salt tolerant as it can bring out more than 90% decolorization up to a salt concentration of 2% (w/v). UV-Visible absorption spectra before and after decolorization suggested that decolorization was due to biodegradation and was further confirmed by FT-IR spectroscopy. Overall results indicate the effectiveness of the strain GSM2 explored for the treatment of textile industry effluents containing various azo dyes. To our knowledge, this could be the first report on biodegradation of Reactive Violet 5 by Paracoccus sp. GSM2.

Prevalence of Mycobacterium tuberculosis with multiple copies of IS6110 elements in Gulbarga, South India.

This study was carried out to ascertain the prevalence of Mycobacterium tuberculosis by insertion sequence 6110 (IS6110) based DNA fingerprinting method in Gulbarga district belonging to the southern part of India. Results showed that among the 52 M. tuberculosis isolates studied, 57.7% exhibited more than 5 copies of IS6110 showing the prevalence of M. tuberculosis with multiple copies of IS6110 elements.

Vancomycin resistance among methicillin resistant Staphylococcus aureus isolates from intensive care units of tertiary care hospitals in Hyderabad.

BACKGROUND & OBJECTIVES: Multidrug resistant methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of nosocomial and community acquired infections and is on the rise. The glycopeptide vancomycin has been proposed as the drug of choice for treating such infections. The present study aimed at identifying the vancomycin resistance both phenotypically and genotypically among the MRSA isolates from two tertiary care hospitals in Hyderabad, south India. METHODS: MRSA were isolated and identified from different clinical samples collected from ICUs of tertiary care hospitals in Hyderabad using conventional methods. Antibiogram of the isolates and vancomycin MIC were determined following CLSI guidelines. vanA was amplified by PCR using standard primers. RESULTS: All vancomycin resistant S. aureus (VRSA) isolates were MRSA. The VRSA isolates were positive for vanA gene, except one which was negative. All VRSA had a vancomycin MIC in the range of 16-64 mg/l. INTERPRETATION & CONCLUSIONS: The increase in vancomycin resistance among MRSA and excessive use of antimicrobial agents have worsened the sensitivity. Larger studies need to be done in various geographical regions of the country to better define the epidemiology, mechanism of vancomycin resistance in S. aureus and its clinical implications.

Comparison of Capsular Typing of Staphylococcus aureus with Bacteriophage Typing: A Study in Gulbarga, India.

Staphylococcus aureus (S. aureus) is important both as a nosocomial and community acquired pathogen causing various degrees of infections. Typing S. aureus has been a question that is still being addressed. Bacteriophage typing is still used as a golden standard for typing though molecular methods are investigated. In developing countries where neither molecular typing nor the bacteriophage typing methods can be routinely used, the recently developed capsular typing method can be considered as screening method. We compared capsular typing with bacteriophage typing of the strains isolated in Gulbarga, India. We observed that the typeability of capsular typing was significantly higher (96%) among the phage typed strains, and the predominant capsular type in the region was type-8. The data so generated can be used to group S. aureus based on capsules both as a screening prior to bacteriophage typing, and to identify capsular candidate for developing prophylactic and therapeutic alternatives.

Bioleaching of copper from chalcopyrite ore by fungi.

Microorganisms have been geologically active in mineral formation, mineral diagenesis and sedimentation via direct action of their enzymes or indirectly through chemical action of their metabolic products. This property of microorganisms is being harnessed during the recent years for extraction of metals from their ores, especially from low-grade ores. In the present study bioleaching of copper from its low-grade chalcopyrite ore using 26 isolates of acidophilic fungi is reported. Most of these fungal strains belonged to the genera Aspergillus, Penicillium and Rhizopus. The leaching experiments were conducted in Czepek Dox minimal medium containing 1% (100 mesh) ore with shaking at room temperature for 20 days. Out of these, 4 isolates exhibited significant bioleaching activities. Maximum leaching of copper (78 mg/L) was observed with Aspergillus flavus (DSF-8) and Aspergillus niger (DOF-1). Nutritional and environmental conditions for optimum bioleaching were standardized. Present study indicates the usefulness of acidophilic fungi in bioleaching of copper from its low-grade ores.

Results of a modified WHO regimen in highly bacilliferous BL/LL patients

regimen consisting of 600 mg of rifampin once a month, 100 mg of clofazimine on alternate days, and 100 mg of dapsone daily was used in 56 untreated, highly bacillated borderline lepromatous/lepromatous (BL/LL) patients with an average bacterial index (BI) of 4.45. Treatment was continued until skin-smear negativity. After 2 years of therapy, none of the patients had become smear negative and the average BI was 2.56. There was no growth on inoculation of skin-tissue biopsies in the normal mouse foot pad after 6 months of therapy. Bacillemia was still detectable in 11/50 patients, and significant ATP levels were detected in Mycobacterium leprae from skin-tissue biopsies in 16% of the cases. After 3 years of therapy, three patients had become smear negative. The average BI was 1.30. None of the patients had detectable bacillemia, and 5% of the cases showed detectable ATP levels in M. leprae from tissue biopsies. After 4 years of therapy, 41.7% of the patients had become smear negative. The average BI was 0.66, and no ATP was detected in any of the purified bacillary suspensions. The fall in BI was accelerated, and more patients on continued treatment became negative earlier compared to those having treatment for a limited duration, as reported by others