Catheter-related blood stream infections: prevalence, risk factors and antimicrobial resistance pattern.

BACKGROUND: Intravascular devices have significant potential for producing iatrogenic diseases resulting in catheter-related blood stream infections (CRBSIs). A study was undertaken to find the prevalence of CRBSI among patients in acute wards and to analyze the associated risk factors, causative pathogens with their antibiotic susceptibility (ABST) patterns. METHODS: Randomly ten days per month were chosen, for a period of two years. All the acute wards patients who were on indwelling blood catheters were identified. Those fulfilling the CRBSI criteria were further worked up for confirmation of diagnosis by differential time to positivity. The catheter tip was cultured by Maki's semiquantitative method. ABST of the isolates obtained was performed by Kirby-Bauer disk diffusion method. RESULTS: The prevalence of CRBSI was found to be 39.25% with the most common organism isolate being Serratia marcescens (23.81%). The immunocompromised status of the patients and catheterisation time were significant risk factors. Methicillin resistance was found to be 33.33% in coagulase-negative staphylococci. The resistance to vancomycin among the Entercoccus faecium isolates was found to be 33.33%. Among the gram negatives, resistance to aminoglycosides, fluoroquinolones and third-generation cephalosporins was high. CONCLUSION: The study highlights the importance of regular surveillance programs, an efficient infection control program, strict adherence to antiseptic measures and use of a rational antibiotic policy for the early diagnosis and better management of CRBSI.

Outbreak of Prototheca wickerhamii algaemia and sepsis in a tertiary care chemotherapy oncology unit.

BACKGROUND: Prototheca is an emerging, opportunistic, pathogenic, zoonotic achlorophyllous green alga, expanding in pathogenicity and host range, causing localized and disseminated infections. This outbreak of Prototheca wickerhamii algaemia and sepsis in a tertiary care 30-bedded chemotherapy oncology unit is the first human outbreak to the best of our knowledge. METHODS: P. wickerhamii algaemia was confirmed on consecutive isolation. Person to person transmission was hypothesized considering all patients in the unit at risk. Clinico-demographic, diagnostic and treatment profile were correlated. Both manual and automated systems were used for blood culture, isolation, identification and susceptibility of Prototheca. Liposomal amphotericin B was given. Outbreak surveillance of faeces, fingertips and environmental reservoirs, retrospective surveillance during past 15 years and prospective surveillance was continued for two years. RESULTS: The outbreak affected 12 neutropenic patients over 50 days. No specific clinical features were noted. The hypothesis could not be substantiated. P. wickerhamii was isolated as yeast-like colonies revealing Gram positive yeast-like cells without budding and pseudohyphae which were confirmed by automated system. Post amphotericin B blood cultures were negative for Prototheca. Surveillance studies were not contributory. CONCLUSION: P. wickerhamii has no documented reservoirs or transmission. Endogenous colonization in the gut followed by translocation during chemotherapy induced immunosuppression is likely to cause algaemia and sepsis. Outbreaks are difficult to detect and control as incubation period is variable and clinical presentation is muted, emphasizing the need to strengthen hospital and laboratory based surveillance systems to ensure adequate preparedness, rapid detection and response to outbreaks.

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for rapid identification of Mycobacterium abscessus.

BACKGROUND: Nontuberculous mycobacteria are increasingly being implicated in infections and have become an important cause of health care associated infections. Mycobacterium abscessus, a rapidly growing mycobacteria, is of particular concern as it tends to be resistant to commonly used therapeutic options. Conventional phenotypic methods for speciation of mycobacteria are time consuming, labor intensive and not always reliable. Molecular methods require expertise and are expensive. The study was used to evaluate the use of matrix associated laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) as a means of rapid identification of M. abscessus. METHODS: 35 isolates of rapidly growing Mycobacterium from an outbreak of surgical site infections at a tertiary care hospital were identified using phenotypic methods. The mycobacterial isolates were inactivated and an extraction protocol was followed. These isolates were then analyzed by MALDI biotyper (Bruker Daltonics) using biotyper software 4.0 and the mycobacterial reference database v 2.0. RESULTS: All 35 isolates were identified as M. abscessus by MALDI biotyper but the scores obtained according to guidelines of the company were lower than previous studies with only 23 out of the 35 isolates having scores of greater 1.8 which was described as the minimum score to be achieved for reliable identification. CONCLUSION: MALDI-TOF MS offers a rapid and inexpensive method for identification of Mycobacteria; however, the scores obtained in our study were lower than reported in other studies.

Point prevalence & risk factor assessment for hospital-acquired infections in a tertiary care hospital in Pune, India.

BACKGROUND & OBJECTIVES: Hospital-acquired infections (HAIs) are a major challenge to patient safety and have serious public health implications by changing the quality of life of patients and sometimes causing disability or even death. The true burden of HAI remains unknown, particularly in developing countries. The objective of this study was to estimate point prevalence of HAI and study the associated risk factors in a tertiary care hospital in Pune, India. METHODS: A series of four cross-sectional point prevalence surveys were carried out between March and August 2014. Data of each patient admitted were collected using a structured data entry form. Centers for Disease Control and Prevention guidelines were used to identify and diagnose patients with HAI. RESULTS: Overall prevalence of HAI was 3.76 per cent. Surgical Intensive Care Unit (ICU) (25%), medical ICU (20%), burns ward (20%) and paediatric ward (12.17%) were identified to have significant association with HAI. Prolonged hospital stay [odds ratio (OR=2.81), mechanical ventilation (OR=18.57), use of urinary catheter (OR=7.89) and exposure to central air-conditioning (OR=8.59) had higher odds of acquiring HAI (P<0.05). INTERPRETATION & CONCLUSIONS: HAI prevalence showed a progressive reduction over successive rounds of survey. Conscious effort needs to be taken by all concerned to reduce the duration of hospital stay. Use of medical devices should be minimized and used judiciously. Healthcare infection control should be a priority of every healthcare provider. Such surveys should be done in different healthcare settings to plan a response to reducing HAI.

Species distribution and antimicrobial resistance pattern of Coagulase-negative Staphylococci at a tertiary care centre.

BACKGROUND: Coagulase-negative Staphylococci (CoNS), previously dismissed at contaminants, have now emerged as an important cause of nosocomial infections especially in patients with implants and prosthetic devices. They are a well-known cause of bloodstream infections, urinary tract infections, wound infections, prosthetic valve endocarditis and eye infections. This study was conducted with an aim to identify CoNS at the species level from various clinical samples and determine the antimicrobial resistance pattern of these isolates. METHODS: This cross sectional study was carried out from September 2011 to February 2014 in which 150 non-repetitive clinical isolates of CoNS were identified at the species level by conventional phenotypic methods. Complete antimicrobial susceptibility profile was also determined by Kirby Bauer disc diffusion method. Susceptibility testing to vancomycin was done by E-test method. RESULTS: Only three species of CoNS were isolated, the most common being Staphylococcusepidermidis (60%) followed by Staphylococcussaprophyticus (27.3%) and Staphylococcushemolyticus (12.7%). Most S. epidermidis were isolated from blood and intravascular catheter tip samples, whereas all S. saprophyticus were isolated from urine samples of female patients. All isolates were found to be resistant to penicillin, but were susceptible to glycopeptides and linezolid and showed variable resistance to fluoroquinolones, aminoglycosides and macrolides. CONCLUSION: CoNS are emerging nosocomial pathogens and should not always be overlooked as contaminants. However, growth of CoNS from blood cultures and intravascular catheter tips should be clinically correlated and carefully interpreted. As many CoNS strains exhibit drug resistance, antimicrobial susceptibility profile should be determined prior to treatment of these infections.

Prevalence and molecular characterization of methicillin resistance among Coagulase-negative Staphylococci at a tertiary care center.

BACKGROUND: Methicillin-resistant Coagulase-negative Staphylococci (MR-CoNS) have emerged as an important cause of nosocomial infections especially in patients with prosthetic devices and implants. This study was conducted with an aim to determine the prevalence of methicillin resistance among CoNS isolates at a tertiary care center by both phenotypic and genotypic methods. METHODS: This cross sectional study was carried out from September 2011 to February 2014 in which 150 non-repetitive clinical isolates of CoNS were identified at the species level by conventional phenotypic methods. Cefoxitin disk (30 µg) diffusion testing was used to determine methicillin resistance and confirmed by detection of mecA gene by polymerase chain reaction (PCR). RESULTS: Out of 150 CoNS isolates, 51 were methicillin resistant by cefoxitin disk diffusion method. Out of these 51 isolates, mecA gene was detected only in 45 isolates. Moreover, mecA gene was also detected in 4 isolates, which were cefoxitin sensitive. Thus, the prevalence of methicillin resistance among CoNS was found to be 32.7% by PCR. CONCLUSION: The prevalence of methicillin resistance among Coagulase-negative Staphylococci (CoNS) was 32.7% by PCR detection of mecA gene. The sensitivity and specificity of cefoxitin disk diffusion method against mecA gene detection by PCR were found to be more than 90%. It can be concluded from this study that cefoxitin disk diffusion test can be used as a useful screening method to detect methicillin resistance among CoNS isolates. However, detection of mecA gene by PCR remains a more accurate method of detecting methicillin resistance among CoNS.

Antimicrobial use and antimicrobial resistance in nosocomial pathogens at a tertiary care hospital in Pune.

BACKGROUND: Resistance to antimicrobial agents is emerging in wide variety of nosocomial and community acquired pathogens. Widespread and often inappropriate use of broad spectrum antimicrobial agents is recognized as a significant contributing factor to the development and spread of bacterial resistance. This study was conducted to gain insight into the prevalent antimicrobial prescribing practices, and antimicrobial resistance pattern in nosocomial pathogens at a tertiary care hospital in Pune, India. METHODS: Series of one day cross sectional point prevalence surveys were carried out on four days between March and August 2014. All eligible in patients were included in the study. A structured data entry form was used to collect the data for each patient. Relevant samples were collected for microbiological examination from all the clinically identified hospital acquired infection cases. RESULTS: 41.73% of the eligible patients (95% CI: 39.52-43.97) had been prescribed at least one antimicrobial during their stay in the hospital. Beta-lactams (38%) were the most prescribed antimicrobials, followed by Protein synthesis inhibitors (24%). Majority of the organisms isolated from Hospital acquired infection (HAI cases) were found to be resistant to the commonly used antimicrobials viz: Cefotaxime, Ceftriaxone, Amikacin, Gentamicin and Monobactams. CONCLUSION: There is need to have regular antimicrobial susceptibility surveillance and dissemination of this information to the clinicians. In addition, emphasis on the rational use of antimicrobials, antimicrobial rotation and strict adherence to the standard treatment guidelines is very essential.

Emergence of multidrug resistant enterococci at a tertiary care centre.

BACKGROUND: Enterococci have assumed great clinical importance because of their increasing resistance to various antimicrobial agents. Thus, knowledge about the antibiogram of these multidrug resistant isolates is of utmost importance in formulating an effective antibiotic policy to treat these infections and reducing the morbidity and mortality. Aim of this study was to assess the antimicrobial resistance pattern of enterococci and determine the prevalence of multidrug resistance among them. METHODS: This cross sectional study was carried out from August 2011 to February 2014, in which 200 non-repetitive clinical isolates of enterococci were included. Antimicrobial susceptibility testing was done by disc diffusion method. Minimum inhibitory concentration (MIC) of gentamicin, streptomycin, vancomycin, teicoplanin and linezolid was determined by E-test method. RESULTS: The prevalence of multidrug resistance among enterococcal isolates was found to be 63%. Varying levels of resistance was seen to various antibiotics. Most of the isolates were resistant to penicillin (95%), ampicillin (95%) and cotrimoxazole (90%). High level aminoglycoside resistance (HLAR) and glycopeptide resistance was seen in 39% and 14% isolates respectively. Only 4 isolates (2%) were found to be resistant to linezolid. CONCLUSION: The prevalence of multidrug resistance among enterococci was found to be 63%, the resistance being more common in Enterococcus faecium as compared to Enterococcus faecalis. The study highlights the emergence and increased prevalence of multidrug resistant enterococci which pose a serious therapeutic challenge.

Heterogeneous vancomycin-intermediate among methicillin resistant Staphylococcus aureus.

BACKGROUND: Hetero-resistance vancomycin intermediate Staphylococcus aureus (hVISA) is phenotype, which on in-vitro susceptibility test is vancomycin susceptible (VSSA) but has a minority population of vancomycin intermediate (VISA). hVISA is responsible for vancomycin treatment failure. Population Analysis Profile- Area under Curve (PAP-AUC) is a test for detection of hVISA; however, this test is unsuitable for clinical microbiology laboratory. Tests, such as Brain Heart Infusion Agar with 6 µg/ml vancomycin (BHIA6V), E test and Macromethod E Test (MET) are available; however reported to have variable results. METHODS: 58 clinical isolates of Methicillin resistant S aureus (MRSA) having MIC of vancomycin more than 1 µg/ml by E test and agar dilution were analyzed by PAP-AUC, BHIA6V and MET. RESULT: The prevalence of hVISA was 6.9%. hVISA isolates were having vancomycin E test MIC >2 µg/ml. Sensitivity of BHIA6V, MET and E test with MIC >2 µg/ml were 0.75, 0.67 and 1.0 respectively; however, positive predictive values (PPV) were 0.43, 0.4 and 0.27 respectively with PAP-AUC. PAP-AUC ratio correlated with MIC by E test and MET. CONCLUSIONS: There is need for screening MRSA isolates showing in-vitro vancomycin susceptibility ≤2 µg/ml by agar dilution method for detection of hVISA. PAP-AUC test is unsuitable for routine laboratory testing. BHIA6V, MET and E test can be used for screening, however have low PPV.

Detection of glycopeptide resistance genes in enterococci by multiplex PCR.

BACKGROUND: Vancomycin Resistant Enterococci (VRE) are a major cause of nosocomial infections. There are various phenotypic and genotypic methods of detection of glycopeptide resistance in enterococci. This study utilizes multiplex PCR for reliable detection of various glycopeptides resistance genes in VRE. METHOD: This study was conducted to detect and to assess the prevalence of vancomycin resistance among enterococci isolates. From October 2011 to June 2013, a total of 96 non-repetitive isolates of enterococci from various clinical samples were analyzed. VRE were identified by Kirby Bauer disc diffusion method with Clinical and Laboratory Standards Institute (CLSI) guidelines. Minimum inhibitory concentration (MIC) of all isolates for vancomycin and teicoplanin was determined by E-test. Multiplex PCR was carried out for all enterococci isolates using six sets of primers. RESULTS: Out of 96 isolates, 14 (14.6%) were found to be resistant to vancomycin by vancomycin E-test method (MIC ≥32 µg/ml). Out of these 14 isolates, 13 were also resistant to teicoplanin (MIC ≥16 µg/ml). VanA gene was detected in all the 14 isolates by Multiplex PCR. One of the PCR amplicons was sent for sequencing and the sequence received was submitted in the GenBank (GenBank accession no. KF181100). CONCLUSION: Prevalence of VRE in this study was 14.6%. Multiplex PCR is a robust, sensitive and specific technique, which can be used for rapid detection of various glycopeptide resistance genes. Rapid identification of patients infected or colonized with VRE is essential for implementation of appropriate control measures to prevent their spread.

Usefulness of enzyme immunoassay (EIA) for screening of anti HIV antibodies in urinary specimens: A comparative analysis.

BACKGROUND: Standard HIV testing is done using serum or plasma. FDA approved ELISA to screen urine for IgG antibodies to HIV-1 in 1996. It is a simple, noninvasive test and is appropriate for developing countries where health care personnel may not be professionally trained or where clean needles for drawing blood may not always be available. METHODS: 436 individuals with high-risk behavior and strong clinical suspicion of HIV infection were screened for IgG antibodies to HIV-1 in urine by ELISA. Urine HIV testing was performed by enzyme immunoassay, at the ongoing Voluntary Confidential Counseling and Testing Center (VCCTC) at a large tertiary care microbiology lab. The individuals enrolled for the study had high-risk exposure to the virus and majorities were from a state with a high incidence of HIV infection. In all individuals, both serum and urine were tested for IgG antibodies to HIV-1. RESULTS: Overall, 135 individuals (30.96%) were HIV-positive, of whom 96 (71%) had never previously tested positive; 87% of those who tested positive received their results, and most were referred for medical care. Sensitivity, specificity and predictive values of HIV-1 urine ELISA test kit were determined. Sensitivity was found to be 89.6%; 95% CI [82.9-94.0], specificity 97.3%; 95% CI [94.6-98.8], positive predictive value 93.8%; 95% CI [87.8-97.1] and negative predictive value 95.4%; 95% CI [92.3-97.4]. CONCLUSION: Efficiency, sensitivity, and specificity of the urine-based screening for HIV-1 test kits were excellent as compared to the reference test.

In vitro vancomycin susceptibility amongst methicillin resistant Staphylococcus aureus.

BACKGROUND: Vancomycin is drug of choice for treatment of Methicillin Resistant Staphylococcus aureus (MRSA) infections. S. aureus with reduced vancomycin susceptibility (SA-RVS) is on rise. Current guidelines of detection of SA-RVS are based on MIC (Minimum Inhibitory Concentration) by broth or agar dilution methods. Vancomycin MIC by E test (Epsilometer Test) is an alternative. A study was undertaken to know the prevalence of SA-RVS and compare vancomycin MIC by agar dilution and E test. METHODS: A prospective study was undertaken at tertiary care hospital; 232 clinical MRSA isolates were included. Vancomycin MIC was undertaken by agar dilution method and E test. RESULTS: All isolates were sensitive to Linezolid. Two MRSA isolates had vancomycin MIC ≥4 µg/ml; vancomycin MIC50 and MIC90 of MRSA isolates was 0.5 and 0.2 µg/ml respectively by agar dilution method. There was agreement over 93.5% isolates in vancomycin susceptibility by agar dilution and E test. E test had sensitivity and positive predictive value of 1.0 (CI - 0.34-1.0) and 0.5 (CI - 0.17-0.83) respectively compare to agar dilution method. CONCLUSIONS: MRSA isolates continues to be susceptible to vancomycin and Linezolid. E test was found equally suitable in initial screening for vancomycin susceptibility. Due to geographic variation in prevalence, there is need of ongoing surveillance of SA-RVC.

Prevalence of inducible clindamycin resistance in Staphylococcus aureus isolated from clinical samples.

BACKGROUND: Therapy for Staphylococcal infections may be complicated by the possibility of inducible macrolide-lincosamide-streptogramin B resistance (MLSBi). We studied the prevalence of MLSBi in community associated (CA) and hospital associated (HA) Staphylococcus aureus isolates from clinical samples. METHODS: A total of 305 strains of S. aureus comprising 140 (45.9%) [95% CI 40.36-51.52] methicillin resistant S. aureus (MRSA) and 165 (54%) [95% CI 48.48-59.64] methicillin-sensitive S. aureus (MSSA) were identified by conventional methods. The double disc test (D test) was applied by placing erythromycin and clindamycin discs to investigate inducible and constitutive MLSBi resistant phenotypes. RESULTS: 16.6% of MRSA showed constitutive resistance and 37.5% inducible MLSBi resistance. Community associated MRSA (CA-MRSA) represented 10% of all isolates and had lower prevalence of MLSBi than hospital associated MRSA (HA-MRSA). CONCLUSION: Routine screening for inducible MLSBi resistance by double disc test can screen for potential treatment failures such that clindamycin can be used effectively and judiciously when indicated for staphylococcal infections especially for treating skin and soft tissue infections (SSTIs) in CA-MRSA due to low prevalence of MLSBi among CA-MRSA.

Possession syndrome at high altitude ( 4575 m/15000 ft ).

In a first of its kind, a 20 year old Hindu, highlander, working girl presented with abnormal behavior, unrelenting symptoms, had limited benefit by usual treatment and was diagnosed as possession syndrome. Exorcism offered symptomatic relief. The girl resumed normal activities with no recurrence in a 12 month follow up. Possession syndrome is explained in both medical and theological perspectives. Modern medicine associates it with a mental illness though True Possession syndrome without associated mental illness has been reported. Theological perspective can be amalgamated with current scientific theory and practice, thereby complimenting existing concepts.

A Rare Case of Hemoglobin E Hemoglobinopathy with Gaucher's Disease.

Hemoglobin (Hb) E mutation is common in north-east part of our country. The natural history of Hb E thalassemia is highly variable. The phenotype, for patients with similar mutations, can range from asymptomatic to transfusion dependent. Our patient presented at 2 years of age with failure to thrive and hepatosplenomegaly. Routine work up revealed microcytic, hypochromic red blood cells. Hb E homozygous was indicated on electrophoresis and hemoglobin HPLC. Evaluation of parents revealed Haemoglobin E trait in both. Therapeutic splenectomy revealed Gaucher-like cells. ß-Glucocerebrosidase levels were low. Presence of Gaucher-like cells with normal ß-glucocerebrosidase (pseudo-Gaucher cells) are known in leukemia, multiple myeloma, thalassemia and mycobacterial infections. Co-existence of Gaucher's disease with Hb E mutation is not reported to the best of our knowledge.