Nidhi Bhardwaj

Salmonella enterica Enteritidis Arthritis Following Trauma in a Child with Thalassemia Major

Osteoarticular infections caused by Non-typhi Salmonella are exceptionally encountered. We report a case of a bacteriologically documented knee joint infection due to Salmonella enterica serotype enteritidis, following trauma in a child with thalassemia major. Emergency arthrotomy combined with antimicrobial therapy was helpful in eradication of infection. Physicians should be aware of this rare manifestation of Non-typhi Salmonella infections in thalassemic patients.

Outbreak of Streptococcus pyogenes emm type 58 in a high dependency unit of a level-1 trauma center of India

Background and Aims: Group A Streptococcus (GAS) can cause illnesses ranging from self-limited to severe, life-threatening, invasive infections. The objective of the following study was to investigate a suspected Streptococcus pyogenes outbreak in a high dependency unit (HDU) of our trauma center. Materials and Methods: All the isolates of beta hemolytic Streptococci were identified by standard microbiological methods, Vitek 2 system and latex agglutination tests. Antimicrobial susceptibility testing was performed as recommended by Clinical Laboratory Standards Institute. Exotoxin genes, including speA, speB, speC, speF, smeZ, ssa, speG, speH, speJ, speL, speM and speI were detected by polymerase chain reaction (PCR). The emm types of isolates of S. pyogenes were determined by sequencing the variable 5’ end of emm gene after amplification by PCR. Results: In a 28 bedded poly-trauma ward with a four bedded HDU three out of four patients developed S. pyogenes emm type 58 infection. The strain was macrolide and tetracycline resistant and produced the Streptococcal pyrogenic exotoxins speB, speC, speG, speF and smeZ. Surveillance sampling was done for investigation from patients, health-care workers and environmental samples. Conclusion: An outbreak of GAS infections was established caused by the uncommonly reported emm type 58. The outbreak was controlled by prompt treatment, intensive surveillance, feedback and training.

Depressed monocytic activity may be a predictor for sepsis

Introduction: Trauma is one of the leading causes of mortality worldwide with infections as important causes of death in such patients. Bacterial infections cause activation of monocytes with excessive synthesis of pro-inflammatory cytokines. Hence, this prospective study was conducted to assess the activity of monocytes in traumatized sepsis patients using flow cytometry and to assess if they have any prognostic potential. Materials and Methods: A total of 16 consecutive trauma patients with sepsis and having positive blood culture were enrolled, along with four healthy controls during the period of March 2013 to July 2013. Blood from septic patients were collected on the same day when blood culture was positive and on days 2 and 5 thereafter. Surface staining for monocytes with CD14 and intracellular staining for interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) was done and results were analyzed by flow cytometer. Procalcitonin (PCT) assay was done using MiniVidas. Complete clinical follow-up was done for the patients. Results: Of the 16 patients, four died due to infections by various microorganisms. Isolated abdominal trauma (25%) was the most common injury among the enrolled patients of sepsis. Levels of TNF-α were significantly decreased when stimulated with lipopolysaccharide in the fatal patients as compared to the healthy controls. Patients having sepsis who survived had an increased level of TNF-α during the follow-up periods. Conclusion: This study showed that activity of monocytes to produce TNF-α and IL-6 were reduced in severe sepsis. Early identification of such immune-paralysis can help in earlier intervention to salvage this vulnerable trauma population.

Bronchoalveolar lavage fluid cytokine bead array profile for prognostication of ventilated trauma patients.

Aim of Study: Ventilator-associated pneumonia (VAP) is a common cause of mortality in trauma patients admitted to Intensive Care Units. The outcome of such patients may be dependent on local host immune response, which may be best reflected in studies using bronchoalveolar lavage (BAL) fluid. The present study was conducted to ascertain the cytokine profile of BAL using the cytometric bead array (CBA) in a flow cytometer and to correlate the levels of Th-1/Th-2 cytokines in BAL with the clinical outcome of ventilated trauma patients. Patients and Methods: BAL was collected from the patients with suspected VAP. CBA was performed to assess the levels of interleukin-4 (IL-4), IL-6, IL-8, IL-1 β, interferon gamma (IFN-γ), and tumor necrosis factor-alpha in the BAL samples. After acquiring the BAL samples on the flow cytometer, the results were generated using FCAP Array™ software. The cytokine profile was correlated to clinical outcomes. Results: A total of forty patients were enrolled during the study period. Of these, 12 patients (30%) had confirmed VAP and 8 (20%) patients had a fatal outcome. The levels of IL-8 and IFN-γ correlated significantly with the development of VAP and elevated IL-6 in BAL was associated with a poor outcome. Conclusion: A proinflammatory response in the form of elevated IL-6 and IL-8 correlated poorly with the clinical outcome. Th-1 response was significantly reduced in patients with VAP. A proinflammatory response in the form of elevated IL-6 and IL-8 correlated poorly with the clinical outcome.

Resistance pattern of mupirocin in methicillin-resistant Staphylococcus aureus in trauma patients and comparison between disc diffusion and E-test for better detection of resistance in low resource countries

Introduction: Mupirocin is an effective antibiotic for elimination of methicillin-resistant Staphylococcus aureus (MRSA) from nasal colonization and has been used to control outbreaks. Current reports show an increasing trend of resistance to this antibiotic. Objective: This study was conducted to analyze the resistance pattern of MRSA to mupirocin among the patients admitted following trauma to an apex trauma care center of India and to compare the efficacy between two methods of antimicrobial sensitivity testing. Materials and Methods: A total of 150 isolates of MRSA from various clinical samples of trauma patients over a period of 2 years were included in this study. These strains were confirmed for MRSA using VITEK® 2 Compact and the Clinical Laboratory Standard Institute disc diffusion methods. The mupirocin susceptibility of the strains was tested by using E-test and 5 μg mupirocin disc in parallel each time, and the results were compared. Results: Clear zones of inhibition were observed in both tests. Though, good correlation was observed between the disc diffusion and E-tests in >98%, E-test showed a tendency to show lower minimum inhibitory concentration (MIC) in the remaining. These finding did not affect the final interpretation or outcomes. Of the total 150 strains, 138 (92%) showed sensitivity with the zone size in the range of 30-45 mm by 5 μg disc; rest (8%) showed sensitivity with the zone in the range of 18-30 mm by 5 μg disc, but 143 (95%) showed MIC ≤ 0.094 μg/ml and 8 (5%) gave MIC ≤ 0.75 μg/ml but ≥0.094 μg/ml by E-test. However, when both tests were compared, 5 (3.3%) showed zone size between 14 and 25 mm with ≤0.75 but >0.25 μg/ml MIC; 7 (5%) falling between 25 and 30 mm zone with MIC of ≤0.25 but >0.094 μg/ml and 138 (92%) showed zone >30 mm with MIC ≤0.094 but >0.064 μg/ml. Conclusions: All the MRSA isolates in our study were sensitive to mupirocin which is an encouraging finding. Though good screening for sensitivity can be done with 5 μg mupirocin disc, E-test provides a much clear and accurate results in clinical set-up. Hence, disc test can be used in resource poor countries and supplemented with E-test when needed.

Clinical and molecular epidemiology of beta-hemolytic streptococcal infections in India.

INTRODUCTION Beta-hemolytic streptococci (βHS) cause a diverse array of human infections. Despite the high number of cases of streptococcal carriers and diseases, studies discerning the molecular epidemiology of βHS in India are limited. This study reports the molecular and clinical epidemiology of beta-hemolytic streptococcal infections from two geographically distinct regions of India. METHODOLOGY A total of 186 isolates of βHS from north and south India were included. The isolates were identified to species level and subjected to antimicrobial susceptibility testing. Polymerase chain reaction (PCR) was done to detect exotoxin genes, and emm types of group A streptococci (GAS) strains were ascertained by sequencing. RESULTS GAS was the most common isolate (71.5%), followed by group G streptococci (GGS) (21%). A large proportion of GAS produced speB (97%), smeZ (89%), speF (91%), and speG (84%). SmeZ was produced by 21% and 50% of GGS and GGS, respectively. A total of 45 different emm types/subtypes were seen in GAS, with emm 11 being the most common. Resistance to tetracycline (73%) and erythromycin (34.5%) was commonly seen in GAS. CONCLUSIONS A high diversity of emm types was seen in Indian GAS isolates with high macrolide and tetracycline resistance. SpeA was less commonly seen in Indian GAS isolates. There was no association between disease severity and exotoxin gene production.

Antimicrobial resistance in beta-haemolytic streptococci in India: A four-year study

Background & objectives: The incidence and severity of invasive and non-invasive infections demonstrate variability over time. The emerging resistance of Group A streptococci (GAS) to commonly used antibiotics is of grave concern. This study was conducted to assess the antimicrobial resistance of beta-haemolytic streptococci (βHS) in India and to ascertain the molecular mechanisms of resistance. Methods: All isolates of βHS from the Trauma Centre of All India Institute of Medical Sciences (AIIMS) (north India), and heavily populated area of old Delhi from 2010 to 2014 and Yashoda Hospital, Secunderabad (in south India, 2010-2012) and preserved isolates of βHS at AIIMS (2005-2009) were included. Phenotypic confirmation was done using conventional methods and the Vitek 2. Antibiotic sensitivity testing was done by disc diffusion and E-test. Detection of resistance genes, erm(A), erm(B), mef(A), tet(M) and tet(O), was done by polymerase chain reaction (PCR). Results: A total of 296 isolates of βHS (240 from north and 21 from south India) were included in the study. Of the 296 βHS, 220 (74%) were GAS, 52 (17.5%) were Group G streptococci and 11 (3.7%), 10 (3.3%) and three (1%) were Group B streptococci, Group C streptococci and Group F streptococci, respectively. A total of 102 (46%) and 174 (79%) isolates were resistant to tetracycline and erythromycin, respectively; a lower resistance to ciprofloxacin (21, 9.5%) was observed. A total of 42 (14%) and 30 (10%) isolates, respectively, were positive for tet(M) and erm(B) genes. Only 13 (5%) isolates were positive for mef(A). None of the isolates were positive for erm(A) and tet(O). There was discordance between the results of E-test and PCR for erythromycin and tetracycline. Interpretation & conclusions: A high level of resistance to erythromycin and tetracycline was seen in βHS in India. Discordance between genotypic and phenotypic results was reported. Absence of erm(A) and tet(O) with high prevalence of tet(M) and erm(B) was observed.

Multiple mutations in lipid-A modification pathway & novel fosA variants in colistin-resistant Klebsiella pneumoniae

Aim: To investigate antimicrobial resistance mechanisms in a cluster of colistin-resistant Klebsiella pneumoniae. Methods: Antimicrobial susceptibility was tested by disk diffusion and broth microdilution. Whole-genome sequencing and genome analysis were performed. Results: The eight colistin-resistant K. pneumoniae isolates belonged to three different clones (ST11, 14 and 231). The eptA and arnT genes from lipid modification pathway had novel (R157S in arnT and Q319R in eptA) and rare mutations (V39L, R152H, S260L and A279G in eptA). Several substitutions were also identified in mgrB, pmrB, phoP and phoQ genes. The mcr genes were absent in all isolates. Isolates had variants from existing classes of fosA gene. Conclusion: Complex combination of mutations might have led to colistin resistance, which suggests that continuous surveillance of molecular mechanisms is required.

Incidence of ventilator-associated pneumonia and impact of multidrug-resistant infections on patient's outcome: Experience at an Apex Trauma Centre in North India

Introduction: Ventilator-associated pneumonia (VAP) remains one of the most common nosocomial infections in the Intensive Care Unit. In the face of extremely high rates of antimicrobial resistance, it is essential to gauge the clinical significance of isolation of multidrug-resistant (MDR) pathogens from clinical samples. This study details the trend of VAP and the clinical significance of isolation of MDR pathogens from respiratory samples at an Indian tertiary care hospital. Methods: The study was conducted over a 5-year period. VAP was diagnosed on the basis of centres for disease control and prevention criteria. The trend in the rates was compared with preventive measures. Phenotypic and genotypic resistance to beta-lactamases was determined using standard methods. The correlation of isolation of a multi-resistant pathogen with the clinical outcome, length of stay and cost of antimicrobial was ascertained. A clone of Acinetobacter baumannii identified through multilocus sequence typing was used to answer the question of whether resistant bugs always have a fatal outcome. Results: The total ventilator days (VDs) for these patients amounted to 36,278. A total of 433 episodes of VAP occurred during the study, amounting to an overall VAP rate of 11.9/1000 VDs. There was a decline in the rates of VAP over the 5-year period, due to intensive surveillance and preventive activities. A. baumannii (54%) was the most common pathogen, followed by Pseudomonas aeruginosa (21%). A high rate of MDR was seen, with the presence of extended-spectrum beta-lactamases, AmpC and carbapenemase genes. The presence of MDR was not always associated with a fatal outcome. Conclusions: Isolation of MDR pathogens from bronchoalveolar lavage does not always adversely affect the outcome of patients. It requires an interdisciplinary team of clinical microbiologists, physicians and hospital infection control nurses, to collectively manage these patients.

First Report on a Cluster of Colistin-Resistant Klebsiella pneumoniae Strains Isolated from a Tertiary Care Center in India: Whole-Genome Shotgun Sequencing

ABSTRACT Klebsiella pneumoniae is a nosocomial pathogen with clinical importance due to its increasing resistance to carbapenems and colistin. Here, we report the genome sequences of eight colistin-resistant K. pneumoniae strains which might help in understanding the molecular mechanism of the species. The sequence data indicate genomes of ~5.2 to 5.4 Mb, along with several plasmids.