Presence of metallo-beta-lactamases (MBL), extended-spectrum beta-lactamase (ESBL) & AmpC positive non-fermenting Gram-negative bacilli among Intensive Care Unit patients with special reference to molecular detection of blaCTX-M & blaAmpC genes.

BACKGROUND & OBJECTIVES: Non-fermenting Gram-negative bacilli (NFGNB) including Pseudomonas aeruginosa and Acinetobacter baumannii have been implicated in a variety of infections, particularly in the Intensive Care Units (ICUs). This study was aimed to overview the burden of multidrug-resistant NFGNB causing infections in ICU and also to assess the occurrence of extended-spectrum beta-lactamases (ESBLs), AmpC and metallo-beta-lactamases (MBLs) among these isolates. METHODS: Bacterial culture, identification and antibiotic susceptibility were carried out. ESBLs and AmpC were detected both phenotypically and genotypically. MBL was detected by modified Hodge and imipenem-ethylenediaminetetraacetic acid double-disc synergy test. RESULTS: NFGNB represented 45 (37%) of total 121 Gram negative isolates. Multidrug resistance was observed in 66.9 per cent and 72.5 per cent isolates of P. aeruginosa and A. baumannii, respectively. Detection by phenotypic methods showed presence of ESBL, AmpC and MBL in 21.4, 51.1 and 21.4 per cent isolates, respectively. When detected genotypically by polymerase chain reaction, ESBL and AmpC were detected in 21.4 and 41.4 per cent of NFGNB isolates, respectively. BlaCTX-M (21.4%) was the most prevalent gene responsible for ESBL production. INTERPRETATION & CONCLUSIONS: Most of the NFGNB isolated from ICU patients were multidrug-resistant and producers of ESBL, AmpC and MBL. A regular surveillance is required to detect ESBL, AmpC and MBL producers, especially in ICU patients.

Trends of drug-resistance-associated mutations in the reverse transcriptase gene of HIV type 1 isolates from North India.

A major cause of failure of antiretroviral therapy (ART) is the presence of drug-resistance-associated mutations in the polymerase gene of HIV-1. The paucity of data regarding potential drug resistance to reverse transcriptase inhibitors (RTIs) prompted us to carry out this study. This information will shed light on the extent of drug resistance already present in HIV strains and will give future directions in patient treatment and in drug design. Drug resistance genotyping of a partial reverse transcriptase gene was done in 103 HIV-1-infected patients, including the ART-naive and ART-experienced population. The drug resistance pattern was analyzed using the Stanford HIV-DR database, the IAS-USA mutation list and the REGA algorithm-v8.0. Subtyping was done using the REGA HIV-1 subtyping tool-v2.01. The majority of our sequences (96 %) were found to be subtype C, and four (3.8 %) were subtype A1. Significant prevalence of DR mutations (28 %) was observed in the RT gene. Major amino acid substitutions were seen at positions 41, 90, 98, 103, 106, 108, 138, 181, 184, 190, 215, and 219, which confer high/intermediate levels of resistance to most RTIs, independently or together. Our results show that there is an urgent need to tailor ART drug regimens to the individual to achieve optimum therapeutic outcome in North India.

Occupational exposure to Aspergillus and aflatoxins among food-grain workers in India.

BACKGROUND: Aflatoxins are a metabolite of Aspergillus molds and are widespread in the natural environment. Workers who handle food grains are at increased risk of exposure to aflatoxins and subsequently certain respiratory conditions. In India, more than half of the employed population is engaged in some type of agricultural work, yet little known about the respiratory problems as a result of exposure to aflatoxins among workers who handle food grains in India. OBJECTIVES: The aim of this study was to determine the risk of occupational exposure to aflatoxins in food-grain workers compared to workers who are not occupationally exposed to food grains. METHODS: Bronchoalveolar lavage (BAL) and serum samples from 46 food-grain workers and 44 non-food-grain workers were analyzed for the presence of aflatoxins. Microscopy and culture of BAL samples were performed to detect Aspergillus species. RESULTS: Aflatoxins were detected in 32·6% of the food-grain workers and 9·1% of non food grain workers (P<0·01). A significant difference was also found in BAL culture for Aspergillus (P<0·01) between the two groups. About 47·8% of the food-grain workers and 11·4% of non-food-grain workers had chronic respiratory symptoms. CONCLUSION: Occupational exposure to aflatoxins in food-grain workers was found to be associated with the increased presence of respiratory symptoms.

A synthetic approach towards drug modification: 2-hydroxy-1-naphthaldehyde based imine-zwitterion preparation, single-crystal study, Hirshfeld surface analysis, and computational investigation.

The current work is about the modification of primary amine functionalized drugs, pyrimethamine and 4-amino-N-(2,3-dihydrothiazol-2-yl)benzenesulfonamide, via condensation reaction with 2-hydroxy-1-naphthaldehyde to produce new organic zwitterionic compounds (E)-1-(((4-(N-(2,3-dihydrothiazol-2-yl)sulfamoyl)phenyl)iminio)methyl)naphthalen-2-olate (DSPIN) and (E)-1-(((4-amino-5-(4-chlorophenyl)-6-ethylpyrimidin-2-yl)iminio)methyl)naphthalen-2-olate (ACPIN) in methanol as a solvent. The crystal structures of both compounds were confirmed to be imine-based zwitterionic products via single-crystal X-ray diffraction (SC-XRD) analysis which indicated that the stabilization of both crystalline compounds is achieved via various noncovalent interactions. The supramolecular assembly in terms of noncovalent interactions was explored by the Hirshfeld surface analysis. Void analysis was carried out to predict the crystal mechanical response. Compound geometries calculated in the DFT (Density Functional Theory) study showed reasonably good agreement with the experimentally determined structural parameters. Frontier molecular orbital (FMO) analysis showed that the DSPIN HOMO/LUMO gap is by 0.15 eV smaller than the ACPIN HOMO/LUMO gap due to some destabilization of the DSPIN HOMO and some stabilization of its LUMO. The results of the charge analysis implied formation of intramolecular hydrogen bonds and suggested formation of intermolecular hydrogen bonding and dipole-dipole and dispersion interactions.

Emergence of drug resistance-associated mutations in HIV-1 subtype C protease gene in north India.

A major cause of anti-retroviral therapy (ART) failure is the drug resistance-associated mutations in polymerase gene of HIV-1. Paucity of data regarding potential drug resistance to protease inhibitors (PIs) prompted us to carry out this study. Drug resistance (DR) genotyping of the entire protease gene was performed in 104 HIV-1 ART-naive and first-line ART-experienced patients. The DR pattern was analyzed using the Stanford HIV-DR database, International AIDS Society-USA mutation list and REGA algorithm version 8.0. Subtyping was done using Mega 4 and REGA HIV-1 subtyping tool-v2.01. Majority of our sequences 98 (96%) were subtype C and remaining four (3.92%) were subtype A1. In three (2.9%) DE patients, major DR-associated mutation at D30 N and M46I positions were detected. Approximately 70% polymorphisms as minor mutations were observed in protease gene, of which 14 distinct amino acids changes were linked to partial DR such as G16E, K20R, M36I, D60E, I62V, L63P, I64M, H69K, T74A/S, V77I, V82I, I85V, L89M, and I93L. The two major and several minor mutations detected in this study confer low/intermediate levels of resistance to most PIs independently or together. Our results conclude that resistance testing in HIV-1-infected patients should be performed before the initiation of PI therapy for better therapeutic outcome in this region. This information not only will shed light on the extent of current DR in HIV strains but also will aid in patient treatment and drug designing.

Development, characterization and efficacy of niosomal diallyl disulfide in treatment of disseminated murine candidiasis.

In the current study, a novel niosome based formulation of diallyl disulfide (DADS) was evaluated for its potential to treat disseminated candidiasis in mouse model. Among various non-ionic surfactants tested, niosome formulation prepared using Span 80 was found to be most efficient in the entrapment of DADS. The DADS loaded niosomes had size dimensions in the range of 140 ± 30 nm with zeta potential of -30.67 ± 4.5. Liver/kidney function tests as well as histopathologic studies suggested that noisome-based DADS formulations are safe at the dose investigated. When administered to Candida albicans infected animals, the DADS bearing niosomal formulation cleared the fungal burden and increased their survival much efficiently than its free form. FROM THE CLINICAL EDITOR: In this study, a novel niosomal formulation of the antifungal DADS was utilized in a murine candidiasis model, resulting in more efficient fungal clearance compared to the free formulation.

Pulmonary aspergillosis and aflatoxins in chronic lung diseases.

Fungal infections of lung have become increasingly common during the last few decades. Aspergillosis and the role of aflatoxins in various chronic lung diseases have not been extensively studied. Bronchoalveolar lavage (BAL) samples and sera from 40 patients of chronic lung diseases were analyzed for galactomannan antigen (GM) and aflatoxin by enzyme-linked immunosorbent assay. Direct microscopy and culture of BAL samples were also done to detect the Aspergillus species. Results revealed that 15 (37.5 %) of the 40 patients had growth of Aspergillus on BAL culture. Out of these culture-positive cases, 13 (86.7 %) patients were positive for galactomannan antigen also. About 62.5 % cases did not show growth of Aspergillus in BAL culture. However, galactomannan antigen could be detected in 20 % of these patients. Overall, 20 % patients were diagnosed as proven invasive fungal disease (IFD), 32.5 % were of probable IFD, 17.5 % of possible IFD. Aspergillus growth was observed in 100 % of proven and 53.8 % of probable IFD cases. Galactomannan antigen was found in 100 % cases of proven and 76.9 % of probable IFD. Ten (25 %) patients were found to be positive for aflatoxins. It was detected in 6 (40 %) of culture-positive cases. About 62.5 % of the cases with proven IFD and 46.1 % of probable IFD had aflatoxin in their samples. Aflatoxin positivity was found to be more in patients with proven IFD than in probable IFD, and higher level of aflatoxins was detected in cases with proven IFD. Significant difference was observed in aflatoxin positivity among food grain workers when compared to other occupations.

Prevalence and assessment of role of SEN virus in acute and chronic hepatitis in India.

BACKGROUND AND AIM: SEN virus (SENV), is a recently discovered single-stranded DNA virus of Annelloviridae family and is believed may play a role in non A-E hepatitis. We conducted this study to identify the prevalence and clinical association of SENV with acute and chronic hepatitis. METHODS: 135 liver disease patients were studied. Extent of liver damage was assessed using the Model for End Stage Liver Disease (MELD) score. A-E viruses and HIV were detected by enzyme immunoassay. Nested PCR was performed for detection of SENV and its genotypes D and H. RESULTS: 34 cases (25.18%) were positive for SEN virus DNA, a statistically significant finding (p < 0.01) of which 22 (64%) had acute viral hepatitis, 4 (11.76%) had chronic viral hepatitis, 3 (8.82%) fulminant hepatic failure and 5 (14.70%) cirrhosis. Mean AST was 47.85 IU/L, ALT 51.2 IU/L and INR 1.73, mean MELD score was 18.38 (11 to 24). 17.64% had severely deranged MELD score. SENV-D genotype was detected in 13 (38%) and SENV-H in 19 (58%) cases. SENV-H occurred in both acute (53%) and chronic hepatitis (47%). SENV-D was strongly associated with acute hepatitis (85%). Cirrhotic and FHF cases were SENV-H positive. 12 (44.11%) were co-infected with HBV, 5 (14.7%) with TTV, 4(11.76%) with HEV, 2 (5.88%) with HCV and 5 (14.4%) with HIV. CONCLUSION: Significant prevalence of SENV in hepatitis patients was observed. On the basis of clinical findings and abnormal liver function tests, we conclude that SENV appears to be not only hepatotropic but also capable of liver damage. Higher prevalence of SENV-H in cirrhotics may point to its possible role in the development of cirrhosis.

Preparation, Crystal Structure, Supramolecular Assembly, and DFT Studies of Two Organic Salts Bearing Pyridine and Pyrimidine.

The effective preparation of two new pyrimidine- and pyridine-based organic crystalline salts with substituted acidic moieties (i.e., (Z)-4-(naphthalen-2-ylamino)-4-oxobut-2-enoic acid (DCNO) and 2-hydroxy-3,5-dinitrobenzoic acid (PCNP)) using methanol as a solvent has been reported. These molecular salts have ionic interactions that are responsible for their structural stabilization in their solid-state assemblies. The crystal structures of DCNO and PCNP were determined by the single-crystal X-ray diffraction (SCXRD) technique. The SCXRD study inferred that cations and anions are strongly packed due to N-H···O, N-H···N, and C-H···O noncovalent interactions in DCNO, whereas in PCNP, N-H···N noncovalent interactions are absent. The noncovalent interactions in both organic crystalline salts were comprehensively investigated by Hirshfeld surface analysis. Further, a detailed density functional theory (DFT) study of both compounds was performed. The optimized structures of both compounds supported the existence of the H-bonding and weak dispersion interactions in the synthesized organic crystalline salt structures. Both compounds were shown to have large and noticeably different HOMO/LUMO energy gaps. The atomic charge analysis results supported the SCXRD and HSA results, showing the formation of intermolecular noncovalent interactions in both organic crystalline salts. The results of the natural bond orbital (NBO) analysis confirmed the existence of (relatively weak) noncovalent interactions between the cation and anion moieties of their organic crystalline salts. The global reactivity parameters (GRPs) analysis showed that both organic crystalline salts' compounds should be quite thermodynamically stable and that DCNO should be less reactive than PCNP. For both compounds, the molecular electrostatic potential (MEP) analysis results support the existence of intermolecular electrostatic interactions in their organic crystalline salts.

Anti-candidal activity of essential oils alone and in combination with amphotericin B or fluconazole against multi-drug resistant isolates of Candida albicans.

Therapy for candidiasis is becoming problematic due to the toxicities of currently available antifungal agents and the increasing prevalence of resistance among the etiologic agents. Therefore, new antifungals and alternative approaches are needed. In this study, 20 fluconazole-resistant strains of Candida albicans were found to have varying levels of resistance to other azoles, i.e., itraconazole (MIC of 4-128 µg/ml) and ketoconazole (2-256 µg/ml). In addition, 13 of these isolates appeared resistant to amphotericin B (32-128 µg/ml). A total of 21 plant essential oils were screened for their antifungal activity against these multi-drug resistant isolates. The oils of Cymbopogon martini, i.e., citral and cinnamaldehyde, exhibited strong inhibitory activity with minimum inhibitory concentrations (MIC(50)) ranging from 90-100 µg/ml. The test oils were more effective than fluconazole and amphotericin B in inhibiting azole- and amphotericin B-resistant, as well as amphotericin B-susceptible isolates. The test oils and especially eugenol, exhibited significant synergy with fluconazole or amphotericin B against the test isolates. These findings suggest the possible effective use of certain oils alone or in combination with fluconazole or amphotericin B, against multi-drug resistant isolates of C. albicans.

Acute lower respiratory tract infections in children.

Acute lower respiratory tract infection (ALRTI) is a common illness, but there have been relatively few studies of the bacterial etiology in developing countries. Nasopharyngeal aspirates of 70 children under 10 years of age with ALRTI were cultured for aerobic bacterial pathogens. Klebsiella pneumoniae was the commonest organism (32.2%) isolated followed by S. pneumoniae (10%), E. coli (10%), P. aeruginosa (5.7%), S. aureus (2.8%) and H. influenzae (1.4%). There were significantly more bacterial pathogens isolated in children <1 year of age (73.7%) than in those > 1 year of age (56.2%) (P=0.03). A shift in spectrum from Gram-positive cocci to Gram negative bacilli in ALRTI was observed in our study.

Frequency of HIV infection amongst children with disseminated tuberculosis and tuberculous meningitis in Aligarh (North India) - a low HIV prevalence area.

OBJECTIVE: To determine frequency of HIV in children with disseminated tuberculosis and tuberculous meningitis in a low HIV prevalence area, and to study clinical profile of those found HIV positive. STUDY DESIGN: Cross-sectional, descriptive study. PLACE AND DURATION OF STUDY: Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, India from February 2005 to January 2008. METHODOLOGY: The study was conducted on 215 children under 14 years of age with either disseminated tuberculosis or tuberculous meningitis. HIV infection was diagnosed in accordance with WHO strategy II. In children younger than 18 months, the strategy (to cut down costs) was to screen first by HIV antibody testing and subject only positive cases to virological tests. Parents of HIV positive children were also tested for HIV and counselled. The clinical profile of HIV positive patients was noted. RESULTS: The frequency of HIV was 5.12%, while that in cases of disseminated tuberculosis was much higher (22%). No case with isolated tuberculous meningitis was HIV positive. The majority (45.45%) of patients with HIV were between 1-5 years of age. The mode of infection in 7 (63.63%) cases was parent to child transmission. Loss of weight, prolonged fever, pallor, hepato-splenomegaly and oral candidiasis were the commonest clinical manifestations among HIV positive patients. CONCLUSION: Clinically directed selective HIV screening in cases of disseminated tuberculosis can pickup undiagnosed cases of the same in areas with low prevalence of HIV infection.

Correlation of HbA1c and S. creatinine along with microbiological profiling of infected ulcers; cases of diabetic patients.

STATEMENT OF THE PROBLEM: The rate of diabetes mellitus is increasing globally as a result of increased levels of blood glucose. The elevated blood glucose level results due to impairment in the production and action of insulin. An increase in glycated hemoglobin is associated with higher blood glucose levels that further results in nephropathy, neuropathy, retinopathy, and cardiovascular disease. Therefore, the study has investigated the correlation between HbA1c and creatinine levels among diabetic patients, suffering from foot ulcerations. METHODS: A prospective cohort hospital based-study has retrieved hospital records of patients during January 2009 and February 2015. A total of 192 patients, admitted in the Rajiv Gandhi Centre for Diabetes and Endocrinology, of Jawaharlal Nehru Medical College Hospital, Aligarh Muslim University, Aligarh, India were recruited. RESULTS: It has been examined that there is a positive correlation between ulcer duration and BMI, amputation rate and BMI, gender and BMI, hospital stay and BMI, HbA1c and BMI, Hb and BMI and triglyceride and BMI at 5% level of significance. CONCLUSION: Findings have shown positive association with gender, diabetes duration, ulcer size, grade of ulcer, amputation rate, hospital stay, Hb, SGOT/AST and triglyceride.

'I decided not to go into surgery due to dress code': a cross-sectional study within the UK investigating experiences of female Muslim medical health professionals on bare below the elbows (BBE) policy and wearing headscarves (hijabs) in theatre.

OBJECTIVES: The objective of this study is to explore the impact of workplace dress code policies and guidance that may influence inclusivity and opportunities in the workplace. DESIGN: Quantitative, self-completion cross-sectional survey. SETTING: British Islamic Medical Association conference. PARTICIPANTS: Eighty-four female medical healthcare professionals with a range of ethnicities and wide geographical coverage. PRIMARY AND SECONDARY OUTCOME MEASURES: The study reports on the experiences of female Muslim healthcare professions wearing the headscarf in theatre and their views of the bare below the elbows (BBE) policy. Percentage of positive answers and their respective 95% CIs are calculated. RESULTS: The majority of participants agreed that wearing the headscarf was important for themselves and their religious beliefs (94.1%), yet over half (51.5%) experienced problems trying to wear a headscarf in theatre; some women felt embarrassed (23.4%), anxious (37.1%) and bullied (36.5%). A variety of different methods in head covering in operating theatres were identified. The majority of respondents (56.3%) felt their religious requirement to cover their arms was not respected by their trust, with nearly three-quarters (74.1%) of respondents not happy with their trust's BBE uniform policy alternative. Dissatisfaction with the current practice of headscarves in theatre and BBE policy was highlighted, with some respondents preferring to specialise as GPs rather than in hospital medicine because of dress code matters. The hijab prototype proposed by the research team also received a positive response (98.7%). CONCLUSIONS: Our study suggests that female Muslims working in the National Health Service (NHS) reported experiencing challenges when wearing the headscarf in theatre and with BBE policy. The NHS needs to make its position clear to avoid variations in individual trust interpretation of dress code policies. This illustrates a wider issue of how policies can be at odds with personal beliefs which may contribute to a reduction in workforce diversity.

Epidemiology of multidrug-resistant Gram-negative pathogens isolated from ventilator-associated pneumonia in ICU patients.

OBJECTIVES: Antibiotic resistance among Gram-negative pathogens isolated from ventilator-associated pneumonia (VAP) poses a grave threat in intensive care unit (ICU) patients. The aim of this study was to assess the prevalence of pathogens in ICU patients and their drug resistance profile. The prevalence of extended-spectrum ß-lactamases (ESBLs), AmpC ß-lactamases and metallo-ß-lactamases (MBLs) was also assessed. METHODS: Tracheal aspirates were collected aseptically from 87 ICU patients between May 2012 and January 2014. Cultured isolates were identified by standard microbiological techniques. Antimicrobial susceptibility testing was performed according to Clinical and Laboratory Standards Institute (CLSI) guidelines. ESBLs and AmpC ß-lactamases were detected both phenotypically and genotypically; MBLs were detected phenotypically. RESULTS: A total of 77 isolate were cultured. Gram-negative bacteria comprised 68 (88.3%) of the total isolates, among which 49 (72.1%) were multidrug-resistant (MDR). Gram-positive organisms comprised four (5.2%) of the total isolates and all four (100%) were MDR. Aspergillus fumigatus (6.4%) was the only fungal pathogen identified. CONCLUSIONS: Pseudomonas aeruginosa was the predominant pathogen associated with VAP. The rising trend of antibiotic resistance in Gram-negative organisms is alarming. Regular monitoring of the pattern of resistance in ICUs is critical in effective management of VAP patients.

Chlamydia trachomatis infection & female infertility.

BACKGROUND & OBJECTIVES: Chlamydia trachomatis is a well recognized sexually transmitted pathogen. Besides its potential to produce genital tract infection, C. trachomatis is increasingly being associated with long-term complications like infertility. The present study was undertaken to assess the role of C. trachomatis in female infertility as such data are lacking. METHODS: Women of primary and secondary infertility (n=110) and 30 healthy term pregnant women as control group were enrolled in the study. Detailed clinical history of each patient was recorded. Hysterosalpingography was performed in all patients. Endocervical swabs were collected for culture on cycloheximide treated McCoy cell line and for antigen detection by ELISA. RESULTS: C. trachomatis was detected in 31 (28.1%) of the 110 infertile women while one (3.3%) in control group was positive for C. trachomatis (P<0.01). Cell culture alone identified 25 (22.72%) patients suffering from chlamydial infection while C. trachomatis antigen was detected by ELISA in 18 (16.37%) patients. The one control case was positive for Chlamydia antigen by ELISA and not by cell culture. Chlamydial positivity was seen in 20 of the 74 (27%) women with primary infertility and in 11 of the 36 (30.6%) with secondary infertility. Of the 58 asymptomatic women, 21(36.2%) had chlamydia infection while among the 52 symptomatic cases 10 (19.2%) were infected; 38 per cent women with chlamydial infection also had tubal occlusion. INTERPRETATION & CONCLUSION: A significantly high rate of C. trachomatis infection was found in infertile women and more so in asymptomatic females and in secondary infertility cases. Lack of symptoms make clinical diagnosis of chlamydial infection difficult. Screening of infertile women for C. trachomatis is therefore recommended so far early therapeutic interventions.

Comparison of different diagnostic techniques in Plasmodium falciparum cerebral malaria.

BACKGROUND & OBJECTIVES: Plasmodium falciparum cerebral malaria remains a major health problem in India. The efficacy of treatment of cerebral malaria lies in its early diagnosis through rapid diagnostic methods. ParaSights-F test detects HRP-2 antigen secreted by parasitised red blood cells and quantitative buffy coat assay (QBC) is examination of buffy coat for the presence of malarial parasite stained with acridine orange. This study was performed to evaluate the effectiveness of ParaSight-F test and QBC assay as diagnostic methods in the patients of cerebral malaria. METHODS: Fifty clinically diagnosed patients of cerebral malaria were included in the study. ParaSight-F test, QBC and conventional blood smear examination was done. Patients who were in coma and there were no obvious features of bacterial or viral etiology were investigated for cerebral malaria by these diagnostic methods. RESULTS: ParaSight-F test, QBC and peripheral blood smears were examined. Patients were followed-up for signs of clinical recovery. ParaSight-F test was positive in 47 patients, QBC in 46 while blood smear examination was positive in 28 cases. INTERPRETATION & CONCLUSION: Sensitivity and specificity of ParaSight-F test were found to be 96.6 and 94% while QBC showed 97.8 and 100% respectively. ParaSight-F test and QBC were found to be novel methods for diagnosis of cerebral malaria especially in the cases where diagnosis can not be made by conventional blood smear examination due to low parasitaemia. These rapid diagnostic methods help in early therapeutic intervention.

Incidence of Multidrug-Resistant Pseudomonas Spp. in ICU Patients with Special Reference to ESBL, AMPC, MBL and Biofilm Production.

BACKGROUND: Multidrug-resistant (MDR) Pseudomonas spp. have been reported to be the important cause of ICU infections. The appearance of ESBL, AmpC and MBL genes and their spread among bacterial pathogens is a matter of great concern. Biofilm production also attributes to antimicrobial resistance due to close cell to cell contact that permits bacteria to more effectively transfer plasmids to one another. This study aimed at determining the incidence of ESBL, AmpC, MBL and biofilm producing Pseudomonas spp. in ICU patients. MATERIAL AND METHODS: The clinical specimens were collected aseptically from 150 ICU patients from February 2012 to October 2013. Identification and antimicrobial susceptibility was performed according to Clinical and Laboratory Standards Institute (CLSI) guidelines. ESBLs and AmpC were detected phenotypically and genotypically. MBL was detected by modified Hodge and imipenem-EDTA double-disk synergy test. RESULTS: Pseudomonas spp. 35(28%) were the most prevalent pathogen in ICU infections. Multidrug resistance and biofilm production was observed in 80.1% and 60.4% isolates, respectively. Prevalence of ESBL, AmpC and MBL was 22.9%, 42.8% and 14.4%, respectively. The average hospital stay was 25 days and was associated with 20% mortality. CONCLUSIONS: A regular surveillance is required to detect ESBL, AmpC and MBL producers especially in ICU patients. Carbapenems should be judiciously used to prevent their spread. The effective antibiotics, such as fluoroquinolones and piperacillin-tazobactum should be used after sensitivity testing.

Resistance due to aminoglycoside modifying enzymes in Pseudomonas aeruginosa isolates from burns patients.

BACKGROUND & OBJECTIVE: Enzymatic modifications of aminoglycosides result in high-level resistance in numerous bacterial species. However, the data on this aspect are elementary in our country. The present study was therefore designed to determine resistance rates and patterns, and to find out the prevalent aminoglycoside modifying enzymes (AMEs) in clinical isolates of Pseudomonas aeruginosa from hospitalized burn patients. METHODS: Forty two, non-repeat, clinical isolates of P. aeruginosa obtained during a period from February to July 2003, were analysed for the presence of antibiotics resistance. On the basis of aminoglycoside susceptibility patterns, resistance phenotypes and possible AMEs were inferred according to interpretative reading. Seven isolates collected during the same period and previously characterized to harbour a 48.5 kb plasmid, encoding multiple drug resistance, were also analysed for aminoglycoside susceptibility patterns, and AMEs encoded by the plasmid were inferred. RESULTS: Ninety six per cent of the isolates were multi drug-resistant and majority (71.4%) were resistant to 5 or more antibiotics. Markedly high resistance to tobramycin (83.6%) and amikacin (55.1%) was noted, whereas gentamicin resistance was present in 32.6 per cent isolates. The enzyme N-acetyl transferases (AAC) viz. AAC(6')-I was the most common isolated AME followed by AAC(3)-II in 42.8 and 20.4 per cent of isolates respectively. The plasmid harbouring isolates belonged to AAC(6') phenotype and the enzyme encoded was inferred to be AAC(6')-I. INTERPRETATION & CONCLUSION: Markedly high resistance to tobramycin and amikacin was noted in the present study. AAC(6')-I was the most common AME and was inferred to be plasmid encoded in R-plasmid harbouring isolates. This is among the premier reports regarding the aminoglycoside resistance due to AMEs especially plasmid encoded, in P. aeruginosa from India. Further studies are required from different parts of the country to findout the prevalence of aminoglycoside resistance due to AMEs in P. aeroginosa isolates.

Synergy of drug combinations in treating multidrug-resistant Pseudomonas aeruginosa.

BACKGROUND: With the emergence of metallo-betalactamases (MBL) in Pseudomonas aeruginosa (P. aeruginosa), the value of carbapenem, the drug of last resort, is being severely compromised. Curtailing the use of carbapenems becomes paramount if resistance is to be reined in. AIMS: To study the role of synergy between combinations of drugs as an alternative treatment choice for P. aeruginosa. Synergy was studied between combinations of levofloxacin with piperacillin-tazobactam and levofloxacin with cefoperazone-sulbactam by time-kill and chequerboard techniques. METHODS: P. aeruginosa were tested for antibiotic susceptibility by the disc diffusion assay (260 isolates) and E-test (60 isolates). Synergy testing by chequerboard and time-kill assays was performed with combinations of piperacillin-tazobactam with levofloxacin (11 isolates) and cefoperazone-sulbactam with levofloxacin (10 isolates). RESULTS: Nearly all isolates were susceptible to piperacillin-tazobactam (96.1 per cent), followed by piperacillin (78.5 per cent). Seventy-one isolates (27.3 per cent) were found to be multidrug resistant and 19.6 per cent were ESBL producers. MIC50 of amikacin was 32µg/ml and MIC90 was 64µg/ml. MIC50 and MIC90 of cefoperazone-sulbactam was 32µg/ml and 64µg/ml, and for levofloxacin it was 10µg/ml and 240µg/ml, respectively. Piperacillin-tazobactam had MIC50 and MIC90 of 5µg/ml and 10µg/ml, respectively. Synergy was noted in 72.7 per cent isolates for levofloxacin and piperacillin-tazobactam combination, the remaining 27.3 per cent isolates showed addition by both chequerboard and time-kill assay. For levofloxacin and cefoperazone-sulbactam, only 30 per cent isolates had synergy, 40 per cent showed addition, 20 per cent indifference, and 10 per cent were antagonistic by the chequerboard method. CONCLUSION: The combination of levofloxacin and piperacillin-tazobactam is a good choice for treatment of such strains.