Review of a 7-year record of the bacteriological profile of airway secretions of children with cystic fibrosis in North India

Background: Cystic fibrosis (CF) is now a recognised entity in India, with prevalence rates between 1/10,000 and 1/50,000. However, no data were available with regard to the profile of respiratory pathogens in the Indian setting. Materials and Methods: The records of respiratory secretion bacterial cultures of children with CF in a tertiary care hospital in North India from January 2010 to December 2016 were reviewed. Culture data were evaluated; the organisms were noted and their antimicrobial susceptibilities were analysed. The microbiological profile and antimicrobial susceptibility pattern of CF patients were evaluated. Results: A total of 445 samples from 146 children were processed, of which 246 (55%) samples showed bacterial growth. Mixed infections 48 (19.5%) were common in older children. Children aged 3–6 months (62.5%) showed the highest culture positivity. The most commonly isolated organisms were Pseudomonas aeruginosa (52.6%) and Staphylococcus aureus. Children with initial cultures positive for P. aeruginosa had 55% of their subsequent cultures showing polymicrobial infections. P. aeruginosa was most susceptible to ciprofloxacin (89%) and piperacillin-tazobactum (88%). Among the staphylococcal isolates, 38% were methicillin-resistant S. aureus (MRSA). The percentage of MRSA increased from 66% in 2010 to 75% in 2012, followed by a decline to 24% in 2016. Conclusions: The pattern of airway colonisation in the Indian setting is different from the Caucasian population, and P. aeruginosa and Burkholderia cepacia complex appear early. Colonisation with P. aeruginosa benefits from therapy. In case of infection, care must be taken while initiating empiric therapy. It should be based on local antibiograms to prevent the emergence of resistant microbes.

Antibiotic-resistant Enterobacteriaceae in healthy gut flora: A report from north Indian semiurban community

Background & objectives: Rampant use of ?-lactam antibiotics in both community and hospitals has transformed the human healthy intestinal gut flora into a reservoir of antibiotic-resistant organisms. This study was conducted to find the faecal presence of antibiotic-resistant Enterobacteriaceae in faecal samples in the community in north India. Methods: In this prospective study, 207 stool samples were collected from apparently healthy individuals residing in a semiurban community in Chandigarh, India, from August to October, 2015. Isolates belonging to family Enterobacteriaceae were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and antibiotic susceptibility was determined using Clinical Laboratory Standard Institute disc diffusion method. Detection of extended spectrum ?-lactamases (TEM, SHV, OXA-1, CTXM 1, CTXM 2, CTXM 9 and CTXM 8/25), carbapenemases (IMP, VIM and KPC) and New Delhi metallo-?-lactamase was done by multiplex PCR. Results: Of the population studied, 55.5 per cent were females and 60 per cent were illiterate or had only primary education; 43.4 per cent individuals were aged <20 yr. Overall, 70.5 per cent of stool samples had antibiotic-resistant isolates. Maximum resistance was seen for cephalosporins (60.4%) followed by fluoroquinolones (41.5%). The multidrug-resistant (MDR) isolates were 2.4 per cent. The most commonly detected genes were TEM, SHV, OXA-1, CTXM-1, CTXM-2, CTXM-9 and CTXM-8/25 ?-lactamases. Escherichia coli was the most common resistant isolate, and TEM was the most common gene detected. Interpretation & conclusions: Overall, 70.5 per cent members of Enterobacteriaceae had antibiotic resistance in the community and 2.4 per cent were MDR. Higher resistance rates were observed for most commonly used drugs such as cephalosporins and fluoroquinolones. High rate of antibiotic-resistant Enterobacteriaceae in gut of healthy individuals points towards the need for active screening and prevention of dissemination.

Molecular characterization & epidemiology of carbapenem-resistant Acinetobacter baumannii collected across India

Background & objectives: Acinetobacter baumannii is an opportunistic pathogen responsible for causing nosocomial infections. A. baumannii develops resistance to various antimicrobial agents including carbapenems, thereby complicating the treatment. This study was performed to characterize the isolates for the presence of various ?-lactamases encoding genes and to type the isolates to compare our clones with the existing international clones across five centres in India. Methods: A total 75 non-repetitive clinical isolates of A. baumannii from five different centres were included in this study. All the isolates were confirmed as A. baumannii by bl aOXA-51-likePCR. Multiplex PCR was performed to identify the presence of extended spectrum ?-lactamases (ESBL) and carbapenemases. Multilocus sequence typing was performed to find the sequence type (ST) of the isolates. e-BURST analysis was done to assign each ST into respective clonal complex. Results: blaOXA-51-likewas present in all the 75 isolates. The predominant Class D carbapenemase was blaOXA-23-likefollowed by Class B carbapenemase, blaNDM-like. Class A carbapenemase was not observed. blaPER-likewas the predominant extended spectrum ?-lactamase. ST-848, ST-451 and ST-195 were the most common STs. Eight-novel STs were identified. e-BURST analysis showed that the 75 A. baumannii isolates were clustered into seven clonal complexes and four singletons, of which, clonal complex 208 was the largest. Interpretation & conclusions: Most of the isolates were grouped under clonal complex 208 which belongs to the international clonal lineage 2. High occurrence of ST-848 carrying blaOXA-23-likegene suggested that ST-848 could be an emerging lineage spreading carbapenem resistance in India.

Molecular characterization of extended-spectrum ?-lactamases among clinical isolates of Escherichia coli & Klebsiella pneumoniae: A multi-centric study from tertiary care hospitals in India

Background & objectives: The increasing prevalence of extended-spectrum ?-lactamases (ESBLs) has abated therapeutic options worldwide. This study was undertaken to investigate the molecular profile and resistance patterns of ESBLs among clinical isolates of Escherichia coli and Klebsiella pneumoniae at four tertiary care centres in India. Methods: Clinical isolates of E. coli and K. pneumoniae were collected from the All India Institute of Medical Sciences (AIIMS), New Delhi; the Jawaharlal Institute of Postgraduate Medical Education & Research (JIPMER), Puducherry; Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh and Christian Medical College (CMC), Vellore, over one and a half year period. Antimicrobial susceptibility was determined by Kirby-Bauer disc diffusion method. ESBLs were confirmed phenotypically, and multiplex PCR was performed to identify genes for ?-lactamases (blaTEM, blaSHV, blaOXA-1, blaCTXM-1, blaCTXM-2, blaCTXM-9 and blaCTXM-15). Results: Among 341 E. coli isolates collected during the study period, 171 (50%) harboured blaTEM, 145 (43%) blaOXA-1,70 (21%) blaCTXM-1, 19 (6%) blaSHV and four (1%) harboured blaCTXM-2. Phenotypically, combined disc test detected ESBL production in 98/298 (33%) E. coli. Among 304 K. pneumoniae isolates, 115 (38%), 89 (29%), 83 (27%), 64 (21%) and two (0.6%) harboured blaTEM, blaOXA-1, blaCTXM-1, blaSHV and blaCTXM-2, respectively. Combined disc test (CDT) detected ESBL production in 42 per cent K. pneumoniae. Most of the blaCTXM-1positive isolates were also blaCTXM-15 positive. The carbapenem susceptibility ranged from 56 to 88 per cent for E. coli and from 20 to 61 per cent for K. pneumoniae. Antibiotic sensitivity patterns showed that colistin (CST) was the most sensitive drug for both E. coli (271/274, 99%) and K. pneumoniae (229/234, 98%). Interpretation & conclusions: The prevalence of ESBL among four study centres varied, and blaTEM, blaOXA-1 and blaCTXM-15 were the most common genotypes in E. coli and K. pneumoniae isolates in India. The growing carbapenem resistance and emerging colistin resistance warrant the judicious use of these antimicrobials.

Pharmacokinetics of colistin in patients with multidrug-resistant Gram-negative infections: A pilot study

Background & objectives: There is little information concerning intravenously (i.v.) administered colistin in patients with multidrug-resistant (MDR) Gram-negative infections. Thus, this pilot prospective study was undertaken to characterize efficacy and pharmacokinetics of colistin in patients with MDR Gram-negative infections. Methods: Nine patients with age >12 yr and MDR Gram-negative infections were included, of whom six were given colistin at the doses of 2 MU, while three patients were given 1 MU i.v. dose every 8 h. Blood samples were collected at different time intervals. Determination of colistin concentration was done by a ultra-high-performance liquid chromatography/mass spectrometry/selected reaction monitoring assay. Results: The area under the plasma concentration-versus-time curve over eight hours (AUC0-8) for colistin after the 1st dose ranged from 3.3 to 16.4 mg議/l (median, 4.59). After the 5th dose, AUC0-8for colistin ranged from 4.4 to 15.8 mg議/l (median, 6.0). With minimal inhibitory concentration (MIC) value of 0.125 mg/l, AUC0-8/MIC ranged from 26.7 to 131.4 (median, 36.7) and 35.5 to 126.0 (median, 48.0) after the 1st and the 5th doses of 2 MU every 8 h, respectively. Interpretation & conclusions: As there is a paucity of information on AUC/MIC for colistin, it may not be possible to conclude whether AUC/MIC values in our patients were adequate. There is a microbiological clearance of organism, which goes in favour of the dosing schedule being adequate. Further studies need to be done to understand the pharmacokinetics of colistin in patients with infections.

Molecular characterisation of antimicrobial resistance in Pseudomonas aeruginosa and Acinetobacter baumannii during 2014 and 2015 collected across India.

Background: Surveillance of antimicrobial resistance (AMR) is of great importance. Pseudomonas aeruginosa and Acinetobacter baumannii are important pathogens and emergence of resistance in these have increased the morbidity and mortality rates. This surveillance study was initiated by the Government of India ‑ Indian Council of Medical Research. The aim of this study is to determine the antimicrobial susceptibility profile and to characterise the enzyme mediated antimicrobial resistance such as extended spectrum beta‑lactamases (ESBLs) and carbapenemases among multidrug‑resistant (MDR) P. aeruginosa and A. baumannii. Materials and Methods: A multi‑centric study was conducted from January 2014 to December 2015 with a total number of 240 MDR P. aeruginosa and 312 MDR A. baumannii isolated from blood, cerebrospinal fluid, respiratory, pus, urine and intra‑abdominal infections. Kirby–Bauer disc diffusion was done to determine the antimicrobial susceptibility profile. Further, MDR isolates were characterised by multiplex polymerase chain reaction to determine the resistance genes for ESBLs and carbapenemases. Results: Among the ESBLs, blaVEB (23%), blaTEM (5%) and blaSHV (0.4%) in P. aeruginosa and blaPER (54%), blaTEM (16%) and blaSHV (1%) in A. baumannii were the most prevalent. Likewise, blaVIM (37%), blaNDM (14%), blaGES (8%) and blaIMP (2%) in P. aeruginosa and blaOXA‑23like (98%), blaOXA‑58like (2%), blaNDM (22%) and blaVIM (3%) in A. baumannii were found to be the most prevalent carbapenemases. blaOXA‑51like gene, intrinsic to A. baumannii was present in all the isolates tested. Conclusion: The data shown highlight the wide difference in the molecular mechanisms of AMR profile between P. aeruginosa and A. baumannii. In P. aeruginosa, plasmid‑mediated mechanisms are much lesser than the chromosomal mediated mechanisms. In A. baumannii, class D oxacillinases are more common than other mechanisms. Continuous surveillance to monitor the trends in AMR among MDR pathogens is important for implementation of infection control and to guide appropriate empirical antimicrobial therapy.

Post‑traumatic endophthalmitis caused by Streptococcus parauberis: First human case report.

A 12‑year‑old boy presented with trauma to left eye with a wooden stick. On examination, there was full thickness corneal laceration with cataractous lens behind the laceration. The laceration was sutured, and intravitreal injections of vancomycin, ceftazidime and clindamycin were administered. Vitreous tap grew Streptococcus parauberis. The isolate was sensitive to amoxicillin, erythromycin and vancomycin, and topical vancomycin was used to treat the infection. We present the first case of human post‑traumatic infective endophthalmitis caused by the rare agent S. parauberis.

Fixed‑dose combinations of antimicrobials: A need for special attention.

Objective: To highlight the issue of freely available fixed‑dose combinations (FDCs) of antimicrobials. Methods: A critique of two such antimicrobial FDCs was undertaken wherein the following aspects were assessed ‑ rational and regulatory issues and justification for clinical use. Available in vitro, in vivo (animals and humans) evidence from published literature was analysed. Conclusions: There are several inadequately addressed aspects of the considered FDCs which are available in Indian market. In view of the growing problem of antimicrobial resistance, this issue must get the required attention.

A comparative study of clinical, biochemical and hematological profiles in smear positive malaria patients: at a tertiary care center located in rural part of Gujarat, India.

Background: Aims and objectives of current study were to study the clinical, biochemical and hematological profiles in smear positive malaria patients and its correlation to immediate outcome of patient. To analyze the biochemical and hematological imbalances and its correlation with clinical presentation and type of malarial parasites. To elucidate the correlation of hematological and biochemical changes in children infected with malaria and their impact on immediate outcome of patients. Methods: All patients admitted with a diagnosis of malaria in department of Pediatrics at Dhiraj Hospital, Piparia, Vadodara, during the study period of January 2013 to June 2014. Sample size was 106 cases. Inclusion criteria for the study was all children under 18 years of age with smear positive malaria cases diagnosed. The study was done after obtaining a detailed history, complete general physical examination and systemic examination. The patients were subjected to relevant investigations. The data regarding patient particulars, diagnosis and investigations is collected in a specially designed case recording form and transferred to a master chart subjected to statistical methods like mean, standard deviation, proportion, percentage calculation and wherever necessary chi square test for proportion are used. Results: Total 106 patients were enrolled in study. Complications of PF (N=31): Jaundice 16%, severe anemia 23%, thrombocytopenia 29%, leukopenia in 23%, hyponatremia in 29.1%, cerebral malaria in 16% and hyperkalemia in 17%. Complications of PV (N=65): Jaundice 20%, severe anemia 20%, thrombocytopenia 18%, leukopenia in 11%, hyponatremia in 44.6%, hyperkalemia in 9%, cerebral malaria in 12.3% and hypoglycemia in 3.77%. Conclusions: The incidence of malaria is higher in males than females. Thrombocytopenia is very common in malaria, but spontaneous bleeding is not so common finding in malaria. Mixed infections behave like falciparum malaria. P. vivax malaria though traditionally considered to be a benign entity can also have a severe and complicated course, which is usually associated with P. falciparum malaria.

Utility of whole‑cell repetitive extragenic palindromic sequence‑based PCR (REP‑PCR) for the rapid detection of nosocomial outbreaks of multidrug resistant organisms: Experience at a tertiary care center in North India.

Background: There is a huge need to develop molecular typing methods which are simple to perform, rapid and cost effective to confirm clonality of nosocomial isolates in outbreak situations. Objectives: The aim of the study was to investigate a hospital outbreak of multi-drug resistant (MDR) Klebsiellapneumoniae septicemia in a paediatric surgery intensive care unit (PSICU) using a repetitive extragenic palindromic polymerase chain reaction (REP‑PCR). Materials and Methods: MDR Klebsiella pneumoniae isolates from an outbreak of nosocomial sepsis were typed byREP‑PCR using consensus primers. Isolates from different intensive care units (ICUs) but with similar antibiogram were also genotyped for comparison. Results and Conclusion: A cluster of twelve MDR K Pneumoniae septicemia cases was identified at the PSICU by genotyping using REP‑PCR. Surveillance cultures failed to pick up any source of infection. REP‑PCR was found to be a rapid and simple tool for investigation outbreaks in hospitals. Due to early detection we could initiate infection control practices with focus on hand washing and prevent the further transmission of the organism.

Invasive bacterial infections in a pediatric oncology unit in a tertiary care center.

BACKGROUND: Multidrug resistant (MDR) pathogens are becoming a major problem worldwide, more so in the immunocompromised hosts resulting in the urgent need of antibiotic stewardship. PURPOSE: To analyze the organisms isolated and the drug resistance pattern in a pediatric oncology unit. RESULTS: Data pertaining to infections with 128 positive cultures in patients with febrile neutropenia over a period of 1-year are presented. The unit antibiotic policy is decided depending on the sensitivity of the prevailing common organisms. We isolated Gram-negative organisms in 56% cases. Escherichia coli and Klebseilla were the most frequent lactose fermenting Gram-negative Bacilli and Pseudomonas and Acinetobacter the nonfermenting Gram-negative Bacilli. Only 20–30% of the Gram-negative organisms cultured were sensitive to a 3rd/4th generation cephalosporin. The combination of a beta-lactam/inhibitor covered 2/3rd of Gram-negative organisms. About 80% of the organisms were sensitive to carbapenems. There was no colistin resistance. About 44% of our cultures grew a Gram-positive bacterial organism and included coagulase negative Staphylococcus. We had an incidence of methicillin resistant Staphylococcus aureus to be 30%. About 30% of the enterococci isolated in our unit were vancomycin-resistant enterococci. About 23% of patients with a positive bacterial culture died. CONCLUSIONS: Infections in pediatric cancer patient’s account for about 15–20% of the deaths in developing countries as these patients are at a high risk for developing MDR infections. Resistance rates among Gram-positive and Gram-negative organisms have increased worldwide. Every unit needs a rational antibiotic policy. Antibiotic de-escalation and judicious decrease in the duration of antibiotics needs to be practiced.

Trends in antimicrobial susceptibility of Salmonella Typhi from North India (2001-2012).

Purpose: Enteric fever is endemic in India with Salmonella Typhi being the major causative agent. Antibiotic therapy constitutes the mainstay of management. The present study was undertaken to find the susceptibility profile of Salmonella enterica var Typhi (S. Typhi) blood isolates in a tertiary care hospital between January 2001 and December 2012. Materials and Methods: A retrospective analysis of laboratory records was carried out. Conventional blood culture method was used until 2009; from January 2010 onwards BACTEC 9240 system has been in use. Salmonella were confirmed by serotyping using group and type specific antisera. Antibiotic susceptibility was performed using the disk diffusion method. In addition 116 isolates were subjected to minimum inhibitory concentration testing for chloramphenicol, ciprofloxacin, amoxicillin and nalidixic acid (NA) using agar dilution and for ceftriaxone and azithromycin using E‑strips (Biomerieux). Result: A total of 1016 typhoidal salmonellae were obtained. The predominant serotype obtained was S. Typhi (852, 83.8%) followed by Salmonella enterica var Paratyphi A (164, 16.2%). We observed a re‑emergence of susceptibility to first line antibiotics and a notable decline in multidrug resistant (MDR) strains. We also found all recent isolates resistant to NA and susceptible to third generation cephalosporins and 84.5% of isolates having decreasing ciprofloxacin susceptibility using revised criteria as per Clinical and Laboratory Standards Institute 2012 guidelines. Conclusion: There has been re‑emergence of susceptibility to first line antibiotics and a notable decline in MDR strains of S. Typhi. We have a very high resistance to NA and decreasing susceptibility to ciprofloxacin. Third generation cephalosporins and azithromycin seem to be effective therapeutic options. Judicious use of these antibiotics is mandatory to prevent emergence of resistant strains.

Doripenem vs meropenem against Pseudomonas and Acinetobacter.

Recently, doripenem has been approved for the treatment of nosocomial pneumonia (NP), including ventilator-associated pneumonia (VAP). The E-test was performed to determine the MICs of doripenem and meropenem in 203 endotracheal aspirate isolates that consisted of 140 Acinetobacter calcoaceticus-Acinetobacter baumannii complexes and 63 Pseudomonas aeruginosa. Doripenem showed minimum concentration necessary for inhibition of 50% (MIC 50 ) of P. aeruginosa isolates at 0.38 mg/L which is several times (84.2 times) lower than the corresponding MIC 50 value of >32 mg/L for meropenem. The MIC 50 and MIC 90 were similar for both the drugs against A. baumannii. Thus, P. aeruginosa was consistently more susceptible than the A. baumannii.

Burkholderia cepacia complex: Beyond pseudomonas and acinetobacter.

Burkholderia cepacia complex (BCC) is an important nosocomial pathogen in hospitalised patients, particularly those with prior broad-spectrum antibacterial therapy. BCC causes infections that include bacteraemia, urinary tract infection, septic arthritis, peritonitis and respiratory tract infection. Due to high intrinsic resistance and being one of the most antimicrobial-resistant organisms encountered in the clinical laboratory, these infections can prove very difficult to treat and, in some cases, result in death. Patients with cystic fibrosis (CF) and those with chronic granulomatous disease are predisposed to infection by BCC bacteria. BCC survives and multiplies in aqueous hospital environments, including disinfectant agents and intravenous fluids, where it may persist for long periods. Outbreaks and pseudo-outbreaks of BCC septicaemia have been documented in intensive care units, oncology units and renal failure patients. BCC is phenotypically unremarkable, and the complex exhibits an extensive diversity of genotypes. BCC is of increasing importance for agriculture and bioremediation because of their antinematodal and antifungal properties as well as their capability to degrade a wide range of toxic compounds. It has always been a tedious task for a routine microbiological laboratory to identify the nonfermenting gram-negative bacilli, and poor laboratory proficiency in identification of this nonfermenter worldwide still prevails. In India, there are no precise reports of the prevalence of BCC infection, and in most cases, these bacteria have been ambiguously reported as nonfermenting gram-negative bacilli or simply Pseudomonas spp. The International Burkholderia cepacia Working Group is open to clinicians and scientists interested in advancing knowledge of BCC infection/colonisation in persons with CF through the collegial exchange of information and promotion of coordinated approaches to research.