Comparison of biofilm formation in clinical isolates of Candida species in a tertiary care center, North India.

Background and Objectives: Biofilms are colonies of microbial cells encased in a self‑produced organic polymeric matrix. The biofilm production is more important for nonalbicans Candida (NAC); as C. albicans possess many other mechanisms to establish infections. Correct identification of Candida species has gained importance due to persistent rise in infections caused by NAC. We sought to isolate, identify Candida species in clinical isolates and study biofilm formation. Materials and Methods: Modified microtiter plate method was performed to study biofilm formation by isolates in Sabouraud’s dextrose broth. It was then quantitatively assessed using a spectrophotometer. Biofilm formation was graded as negative, +1, +2, +3 and + 4 on the basis of percentage absorbance. Results: Biofilm formation was observed in 16 of 40 (40.0%) isolates of C. albicans as compared to 39 of 78 (50.0%) of isolates of NAC. Strong (+4) biofilm production was seen in maximum biofilm producers in C. tropicalis (12 of 27) followed by C. albicans (8 of 16). Total biofilm producers were significantly more among high vaginal swab isolates 63.2% (12 of 19) and urine isolates 59.2% (29 of 49), when compared to blood isolates 34.2% (13 of 38) as well as other isolates 27.5% (11 of 40). Interpretation and Conclusions: NAC species are qualitatively and quantitatively superior biofilm producers than C. albicans. Biofilm production is the most important virulence factor of NAC species and compared to other lesions, it is more significantly associated with luminal infections.

Evaluation of phenotypic tests for detection of Klebsiella pneumoniae carbapenemase and metallo-beta-lactamase in clinical isolates of Escherichia coli and Klebsiella species.

Context: Carbapenemase production is an important mechanism responsible for carbapenem resistance. Aims: Phenotypic detection and differentiation of types of carbapenemase in carbapenem resistant Enterobacteriaceae is important for proper infection control and appropriate patient management. Settings and Design: We planned a study to determine the occurrence of Class A Klebsiella pneumoniae carbapenemase (KPC type) and Class B Metallo-β-lactamase (MBL type) carbapenemase in hospital and community. Materials and Methods: Clinical isolates of Escherichia coli and Klebsiella species and simultaneously evaluate different phenotypic methods for detection of carbapenemases. Results: It was observed that 20.72% clinical isolates of E. coli and Klebsiella spp. were resistant to carbapenem on screening of which, 14.64% were E. coli and 29.69% were Klebsiella spp. Using phenotypic confirmatory tests the occurrence of carbapenemase production was found to be 87.01% in E. coli and 91.51% in Klebsiella spp. using both modified Hodge test (MHT) and combined disk test (CDT) using imipenem-ethylenediaminetetraacetic acid. Conclusions: Both MBL and KPC type carbapenemases were seen among clinical isolates of E. coli and Klebsiella spp. CDT is simple, rapid and technically less demanding procedure, which can be used in all clinical laboratories. Supplementing MHT with CDT is reliable phenotypic tests to identify the class A and class B carbapenemase producers.

Comparison between the conventional method & molecular line probe assay for identification & drug sensitivity of mycobacteria tuberculosis from clinical specimens.

Rapid susceptibility testing of Mycobacterium tuberculosis strains is imperative for therapy selection but traditional drug susceptibility tests take weeks or are expensive. Classical drug susceptibility (DST) may take up to 2 to 4 months. The line probe assay is a commercially available line-probe assay that rapidly detects Mycobacterium tuberculosis (MTB) complex, as well as the most common mutations associated with rifampicin and isoniazid. In this study we assessed the sensitivity and specificity of the rapid molecular method in comparison with the conventional method.

Extended spectrum beta lactamase producing Proteus penneri: A rare missed pathogen.

Indole negative Proteus species are invariably incorrectly identified as Proteus mirabilis, often missing out isolates of Proteus penneri. We report a case of extended spectrum beta lactamase producing and multidrug-resistant P. penneri isolated from pus from pressure sore of a patient of road traffic accident. Correct and rapid isolation and identification of such resistant pathogen are important as they are significant nosocomial threat.

Genotype MTBDR plus assay for molecular detection of rifampicin and isoniazid resistance in Mycobacterium tuberculosis.

Aim: This study was performed for the rapid identification of Mycobacterium tuberculosis complex and its resistance to rifampicin and isoniazid, directly from the sputum samples of pulmonary tuberculosis patients. Materials and Methods: A commercially available genotype MTBDR plus assay was used for the identification and detection of mutations in Mycobacterial isolates. A total of 100 sputum samples of pulmonary tuberculosis patients were analyzed by using the genotype MTBDR plus assay. The MTBDR plus assay is designed to detect the mutations in the hotspot region of rpoB gene, katG and regulatory region of inhA gene. Results: The genotype MTBDR plus assay detected 22% multidrug resistant (MDR), 2% rifampicin (RMP) monoresistant and 1% isoniazid (INH) monoresistant isolates. In 22 MDR isolates, the codons most frequently involved in RMP-associated mutations were codon 531 (54.55%), 516 (31.82%) and 526 (13.63%), and 90.90% of MDR isolates showed KatG S315T mutations and 9.1% showed inhA C-15T mutations associated with INH resistance. Conclusion: The new genotype MTBDR plus assay represents a rapid, reliable tool for the detection of MDR-TB, wherein results are obtained in 5 h allowing early and appropriate treatment, which is essential to cut the transmission path and reduce the spread of MDR-TB. The genotype MTBDR plus assay can readily be included in a routine laboratory work for the early diagnosis and control of MDR-TB.

Prevalence of HIV, Hepatitis B and Hepatitis C infection in Thalassemia major patients in tertiary care hospital, Gujarat.

Background: Children suffering from beta thalassemia major, due to various genetic defects, have deficient synthesis of ß globin chain of Hemoglobin. This leads to severe anemia, general fatigue and debility asking for repeated or frequent blood transfusion. On the other hand repeated blood transfusions such expose them to dangerous infections such as HIV, HBV and HCV. Aim: The aim of this study was to determine the prevalence of HIV, HBV and HCV infection among thalassemia major patients in an apex tertiary care hospital of Gujarat in west India. Materials and methods: Data were obtained from 100 ß thalassemia major patients attending thalassemia clinic for blood transfusion at regular interval in an apex tertiary care hospital of Gujarat between April 2008 and September 2008. Their laboratory results were subsequently analyzed. Results: Out of 100 patients 65 and 35 were male and female respectively. 18 (18%) patients were found Anti HCV Ab positive, 6 (6%) were found HBsAg positive and 9(9%) patients were Anti HIV 1 and or 2 Ab positive. Older age, more number of transfusions were associated with increased chances of the test to come positive suggestive of infection with respective virus. Completion of vaccination against HBV, completely or partially, was associated with less chances getting infection with HBV Conclusion: The prevalence of HCV infection is much higher compared to HBV and HIV infection due to possibly infected blood transfusion among thalassemia major patients. Screening of Anti HCV Ab detection with highly sensitive and specific test for donated blood is mandatory. Techniques like P24 Antigen detection or RT-PCR should be introduced to shorten the window period for detection of HIV infected donated blood.

Physician accessories: Doctor, what you carry is every patient's worry.

Background: Nosocomial infections are on the rise worldwide and many a times they are carried by the health care personnel. Accessories used by physicians and healthcare personnel can be a potential source of nosocomial infection. Materials and Methods: We designed a survey with the aim to investigate the prevalence of microbial flora of accessories such as pens, stethoscopes, cell phones and white coat used by the physicians working in a tertiary care hospital. Observations: It was observed that 66% of the pens, 55% of the stethoscopes, 47.61% of the cell phones and 28.46% of the white coats used by the doctors were colonized with various microorganisms. Staphylococcus spp. was the predominant isolate followed by Escherichia coli. Methicillin resistance in Staphylococcus aureus was also found, which was a matter of concern. Conclusions: Awareness of appropriate hand hygiene is important in order to prevent potential transmission to patients.