A pilot study to determine Neisseria gonorrhoeae–Chlamydia trachomatis coinfection rates in symptomatic patients attending STI Clinics, New Delhi, India

Background: Neisseria gonorrhoeae and Chlamydia trachomatis are the two most prevalent bacterial sexually transmitted infections. For over two decades, treatment guidelines have recommended empirical co-treatment for N.gonorrhoeae and C.trachomatis as symptoms overlap and co-infection is common. Studies from India estimating the same are limited and mostly based on conventional techniques. Aim and Objective: The aim of this study was to determine the frequency of N.gonorrhoeae and C.trachomatis coinfection using nucleic acid amplification tests. Further, we assessed the utility of pus cell estimation in Gram stained smears as a screening tool for inclusion of samples for molecular diagnosis. Methods: This was a prospective study conducted at two tertiary care hospitals; 100 patients (55 females and 45 males) with genitourinary discharge attending STI clinics were recruited, and endocervical or urethral swabs were collected. PCRs for N.gonorrhoeae and C.trachomatis were put up. In addition, microscopy and culture for gonococcus was performed followed by antimicrobial susceptibility testing. Statistical analysis was performed using the SPSS 16 software. Results: N.gonorrhoeae infection was more common than C.trachomatis. A total of 14 patients were positive by PCR (9 males and 5 females) for gonococcus. However, culture was positive only in 8 male patients. PCR for C.trachomatis was positive in 9 (4 males and 5 females) and the co-infection rate was 5%. The sensitivity and negative predictive value of pus cell estimation was 100% for males and 64% and 94.6% respectively for females. All isolates were susceptible to extended spectrum cephalosporins and azithromycin. Limitation: The sample size of the study was small. Conclusion: Frequency of N.gonorrhoeae/C.trachomatis coinfection in symptomatic STI patients is low. Coinfection is considerably overestimated and necessary confirmation of etiological diagnosis could reduce widespread empirical administration of broad-spectrum antibiotics.

Corynebacterium striatum: An emerging nosocomial skin and soft-tissue pathogen

The genus Corynebacterium is composed of Gram-positive, aerobic, non-motile, non-spore-forming bacilli that are widely distributed throughout the environment. They are usually found as commensals on the skin and are often considered as mere contaminants when isolated from clinical samples. We describe a patient with skin and soft-tissue infections due to Corynebacterium striatum following exploratory laparotomy identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. The clinical importance and pathogenic potential of Corynebacterium species, especially C. striatum, cannot be underestimated. This report is a reminder to physicians of the possible pathogenicity of non-diphtherial Corynebacteria.

Risk Factors for Central line – associated Bloodstream Infections.

Objective: To carry out surveillance of central line – associated bloodstream infections in a Pediatric intensive care unit (PICU) and determine associated risk factors. Methods: This prospective study was conducted over 1.5 years in the PICU. CDC definitions for these infections were followed and associated risk factors were identified. Results: Of 265 enrolled children with central line, 13 developed blood stream infections (incidence density 5.03/1000 central-line days). Significant risk factors included changing the central-line, especially triple lumen, and frequently accessing the central-line. Conclusion: Central-line associated bloodstream infections are preventable primary bacteremias and intervention strategies for prevention should be based on evidence generated to devise future protocols.

Healthcare associated infections in Paediatric Intensive Care Unit of a tertiary care hospital in India: Hospital stay & extra costs.

Background & objectives: Healthcare associated infections (HAIs) increase the length of stay in the hospital and consequently costs as reported from studies done in developed countries. The current study was undertaken to evaluate the impact of HAIs on length of stay and costs of health care in children admitted to Paediatric Intensive Care Unit (PICU) of a tertiary care hospital in north India. Methods: This prospective study was done in the seven bedded PICU of a large multi-specialty tertiary care hospital in New Delhi, India. A total of 20 children with HAI (cases) and 35 children without HAI (controls), admitted to the PICU during the study period (January 2012 to June 2012), were matched for gender, age, and average severity of illness score. Each patient’s length of stay was obtained prospectively. Costs of healthcare were estimated according to traditional and time driven activity based costing methods approach. Results: The median extra length of PICU stay for children with HAI (cases), compared with children with no HAI (controls), was seven days (IQR 3-16). The mean total costs of patients with and without HAI were ` 2,04,787 (US$ 3,413) and ` 56,587 (US$ 943), respectively and the mean difference in the total cost between cases and controls was ` 1,48,200 (95% CI 55,716 to 2,40,685, P<0.01). Interpretation & conclusions: This study highlights the effect of HAI on costs for PICU patients, especially costs due to prolongation of hospital stay, and suggests the need to develop effective strategies for prevention of HAI to reduce costs of health care.

Volume, conductivity, and scatter parameters as diagnostic aid to bacterial sepsis: A tertiary care experience.

Introduction and Materials and Methods: Early diagnosis of sepsis is extremely important to reduce high mortality and morbidity. In this study, clinical usefulness of the volume, conductivity and scatter parameters (mean channels of cell volume, conductivity, and light scatter) in neutrophils was analyzed for predicting acute bacterial infection, which are obtained by the Coulter LH 750 Hematology Analyzer (Beckman Coulter, Fullerton, CA, USA) during automated differential counts. Results: Peripheral blood samples from 162 patients with positive blood cultures for bacteria and 40 healthy controls were studied. We observed a significant increase in the mean channel of neutrophil volume (MNV) from septic patients compared with control subjects (156 ± 13.5 vs. 143 ± 4.8; P < 001). Discussion and Conclusion: An elevation of the MNV was associated with a higher white blood cell count and percentage of neutrophils and was present even in patients who did not have leukocytosis or neutrophilia. With a cut-off of 149 for the MNV, a specificity of 91.4% and sensitivity of 88.7% were achieved. As a quantitative, objective, and more sensitive parameter, we propose that the MNV has a potential to be an additional indicator for acute bacterial infection.

Hand Hygiene Compliance of Healthcare Workers in a Pediatric Intensive Care Unit.

We conducted an observational study over 11 months to assess the hand-hygiene compliance of health-care workers in a Pediatric intensive care unit. The overall compliance was 80.9%, which decreased with increase in workload (79.2% vs. 82.9%). Assessment of hand hygiene compliance helps understand the gaps in practices followed by healthcare workers, and plan effective protocols.

Induction of resistant mutants of Salmonella enterica serotype Typhi under ciprofloxacin selective pressure.

Background & objectives: Infection with Salmonella enterica serovar Typhi (hereafter S. Typhi) is an important public health problem in India. There has been an increase in the number of reported clinical failures to ciprofloxacin treatment but the data on possible mechanism of failure are limited. One mechanism that has been widely reported and found associated with ciprofloxacin resistance, is the mutations in target genes in QRDR (quinolone resistance determining region). It is hypothesized that mutations in DNA gyrase or topoisomerase IV result in therapeutic failure under selective pressure of antibiotic while the patient is on treatment. We undertook in vitro sequential selection studies to expose the clinical isolates of S. Typhi to different concentration of ciprofloxacin to study the role of antibiotic selective pressure in the development of mutations in QRDR. Methods: Total 26 clinical isolates were divided in to two parts: part I included six isolates obtained from three patients with relapse of enteric fever and part II included 20 isolates with different ciprofloxacin MIC levels. For in vitro induction of mutation experiment, five S. Typhi isolates were selected which included three NAS (nalidixic acid sensitive) and 2 NAR (nalidixic acid resistant) S. Typhi. These isolates were grown under increasing concentrations of ciprofloxacin and mutations acquired in QRDR of DNA gyrase (gyrA and gyrB) and topoisomerase IV (parC and parE) were investigated by sequencing. Results: For the isolates included in the part I of the study, it was found that the MIC to ciprofloxacin increased in the isolates obtained during the relapse of enteric fever as compare to the first isolate. All isolates had single mutation in gyrA gene at S83 without additional mutation in the second isolate. In the second part of the study, the nine isolates with varying MICs to ciprofloxacin also had single mutation in gyrA gene at S83 and another six had triple mutations, two mutations in gyrA gene (at S83 and D87) and one mutation in parC gene (at S80). In in vitro induction of mutation experiment, all mutated isolates showed triple mutation (two mutation in gyrA and one in parC gene) while no mutations were found in wild isolates. Interpretation & conclusions: Upon exposure to the step-wise increased concentration of ciprofloxacin, isolates become more tolerant to the ciprofloxacin and showed 2-4 fold higher MICs without new mutation after 8 μg/ml. So the accumulation of mutations under continuous ciprofloxacin pressure and tolerance of the mutant isolates led to the clinical failure. These results also suggested that there could be another mechanism responsible for resistance.

Antibiotic susceptibilities, streptococcal pyrogenic exotoxin gene profiles among clinical isolates of group C or G Streptococcus dysgalactiae subsp. equisimilis & of group G S. anginosus group at a tertiary care centre.

Background & objectives: Group C and group G streptococci (together GCGS) are often regarded as commensal bacteria and their role in streptococcal disease burden is under-recognized. While reports of recovery of GCGS from normally sterile body sites are increasing, their resistance to macrolides, fluoroquinolone further warrants all invasive β haemolytic streptococci to be identified to the species level and accurately tested for antimicrobial susceptibility. This study was aimed to determine the prevalence, clinical profile, antimicrobial susceptibility and streptococcal pyrogenic exotoxin gene profile (speA, speB, speC, speF, smeZ, speI, speM, speG, speH and ssa) of GCGS obtained over a period of two years at a tertiary care centre from north India. Methods: The clinical samples were processed as per standard microbiological techniques. β-haemolytic streptococci (BHS) were characterized and grouped. Antimicrobial susceptibility of GCGS was performed using disk diffusion method. All GCGS were characterized for the presence of streptococcal pyrogenic exotoxins (spe) and spe genes were amplified by PCR method. Results: GCGS (23 GGS, 2GCS) comprised 16 per cent of β haemolytic streptococci (25/142 βHS, 16%) isolated over the study period. Of the 25 GCGS, 22 (88%) were recovered from pus, two (8%) from respiratory tract, whereas one isolate was recovered from blood of a fatal case of septicaemia. Of the total 23 GGS isolates, 18 (78%) were identified as Streptococcus dysgalactiae subsp equisimilis (SDSE, large-colony phenotype), five (21%) were Streptococcus anginosus group (SAG, small-colony phenotype). The two GCS were identified as SDSE. All GCGS isolates were susceptible to penicillin, vancomycin, and linezolid. Tetracycline resistance was noted in 50 per cent of SDSE isolates. The rates of macrolide and fluoroquinolone resistance in SDSE were low. Twelve of the 20 SDSE isolates were positive for one or more spe genes, with five of the SDSE isolates simultaneously carrying speA+ speB+ smeZ+ speF or speB+ smeZ+speF, speI+speM+speG+speH or, speI+spe M+speH or speA+ speB+ speC+ smeZ+ speF. One notable finding was the presence of spe B in four of the five isolates of the Streptococcus anginosus group. No isolate was positive for ssa. Interpretation & conclusions: Our study showed no association between GCGS isolates harbouring streptococcal pyrogenic exotoxins and disease severity. This might be attributed to the small sample size of spe-positive isolates.

Prospective study estimating healthcare associated infections in a paediatric hemato-oncology unit of a tertiary care hospital in north India.

Background & objectives: Healthcare associated infections (HAIs) are responsible for morbidity and mortality among immunocompromised and critically ill patients. We undertook this study to estimate the burden of HAIs in the paediatric cancer patients in a tertiary care hospital in north India. Methods: This prospective, observational study, based on active surveillance for a period of 11 months was undertaken in a 4-bedded isolated, cubicle for paediatric cancer patients. Patients who stayed in the cubicle for ≥48 h, were followed prospectively for the development of HAIs. Results: Of the 138 patients, 13 developed 14 episodes of HAIs during the study period. Patient-days calculated were 1273 days. Crude infection rate (CIR) and incidence density (ID) of all HAIs were 9.4/100 patients and 11/1000 patient-days, respectively. Of the 14 episodes of HAIs, seven (50%) were of blood stream infections (HA-BSI), five (36%) of pneumonia (HAP) and two (14%) urinary tract infections (HA-UTI). The CIRs of HA-BSI, HAP and HA-UTI were 5.1, 3.6 and 1.4/100 patients, respectively. The corresponding IDs were 5.5, 3.9 and 1.6/1000 patient-days, respectively. Mean length of stay was significantly higher in patients who developed an HAI [13.8 (range 7-30), median (Interquartile range) 12 (11-14)] vs 7.5 days [range 2-28, median (interquartile range) 7 (5-9); P<0.0001]. Also mortality was significantly higher in patients who developed an HAI [23% (3/13) vs 3% (4/125), P<0.05]. Interpretation & conclusions: The incidence of HAIs in the paediatric cancer patients in the study was 11/1000 patient days, of which HA-BSIs were the commonest. HAIs were associated with an increase in morbidity and mortality amongst this high risk patient population.

Multiple locus sequence typing of Salmonella Typhi, isolated in north India - a preliminary study.

Background & objectives: In India enteric fever is a major public health problem and Salmonella Typhi is the most common aetiologic agent. Any control strategy for such infections depends to a large extent on the understanding of the disease and relatedness of strains across the world. Multi locus sequence typing (MLST) is one such method of genotyping of bacteria based upon housekeeping genes of known function and chromosome position. MLST data of pathogens are important to determine the molecular evolution by a stable and reproducible method. This study was undertaken to determine the sequence types of representatives S. Typhi isolates obtained from enteric fever patients in a tertiary care centre in north India, over a period of 20 years (1990-2010). Methods: A total of 30 representative isolates of S. Typhi identified by biochemical and serological tests were subjected to multi locus sequence typing (MLST). Seven housekeeping genes of known function and chromosome position were used for the typing by MLST. Sequencing was carried out by using an automated DNA sequencer and results were analyzed to generate phylogenetic tree. Results: MLST pattern grouped S. Typhi into two sequence types- ST1 and ST2. ST1 was predominantly present followed by ST2. Interpretation & conclusions: By MLST the presence of both sequence types, ST1 and ST2, was found in S. Typhi isolates in our region. Predominately ST1 was present followed by ST2. These preliminary results corroborate the global distribution of both sequence types of S. Typhi and also emphasize for the continuous screening of S. Typhi.

Prospective multi-centre sentinel surveillance for Haemophilus influenzae type b & other bacterial meningitis in Indian children.

Background & objectives: Haemophilus influenzae type b (Hib) is one of the leading bacterial causes of invasive disease in populations without access to Hib conjugate vaccines (Hib-CV). India has recently decided to introduce Hib-CV into the routine immunization programme in selected States. Longitudinal data quantifying the burden of bacterial meningitis and the proportion of disease caused by various bacteria are needed to track the impact of Hib-CV once introduced. A hospital-based sentinel surveillance network was established at four places in the country and this study reports the results of this ongoing surveillance. Methods: Children aged 1 to 23 months with suspected bacterial meningitis were enrolled in Chennai, Lucknow, New Delhi, and Vellore between July 2008 and June 2010. All cerebrospinal fluid (CSF) samples were tested using cytological, biochemical, and culture methods. Samples with abnormal CSF (≥10 WBC per μl) were tested by latex agglutination test for common paediatric bacterial meningitis pathogens. Results: A total of 708 patients with abnormal CSF were identified, 89 of whom had a bacterial pathogen confirmed. Hib accounted for the majority of bacteriologically confirmed cases, 62 (70%), while Streptococcus pneumoniae and group B Streptococcus were identified in 12 (13%) and seven (8%) cases, respectively. The other eight cases were a mix of other bacteria. The proportion of abnormal CSF and probable bacterial meningitis that was caused by Hib was 74 and 58 per cent lower at Christian Medical College (CMC), Vellore, which had a 41 per cent coverage of Hib-CV among all suspected meningitis cases, compared to the combined average proportion at the other three centres where a coverage between 1 and 8 per cent was seen (P<0.001 and P= 0.05, respectively). Interpretation & conclusions: Hib was found to be the predominant cause of bacterial meningitis in young children in diverse geographic locations in India. Possible indications of herd immunity was seen at CMC compared to sites with low immunization coverage with Hib-CV. As Hib is the most common pathogen in bacterial meningitis, Hib-CV would have a large impact on bacterial meningitis in Indian children.

Methicillin resistant Staphylococcus aureus (MRSA) in India Prevalence & susceptibility pattern.

Background & objectives: Methicillin resistant Staphylococcus aureus (MRSA) is endemic in India and is a dangerous pathogen for hospital acquired infections. This study was conducted in 15 Indian tertiary care centres during a two year period from January 2008 to December 2009 to determine the prevalence of MRSA and susceptibility pattern of S. aureus isolates in India. Methods: All S. aureus isolates obtained during the study period in the participating centres were included in the study. Each centre compiled their data in a predefined template which included data of the antimicrobial susceptibility pattern, location of the patient and specimen type. The data in the submitted templates were collated and analysed. Results: A total of 26310 isolates were included in the study. The overall prevalence of methicillin resistance during the study period was 41 per cent. Isolation rates for MRSA from outpatients, ward inpatients and ICU were 28, 42 and 43 per cent, respectively in 2008 and 27, 49 and 47 per cent, respectively in 2009. The majority of S. aureus isolates was obtained from patients with skin and soft tissue infections followed by those suffering from blood stream infections and respiratory infections. Susceptibility to ciprofloxacin was low in both MSSA (53%) and MRSA (21%). MSSA isolates showed a higher susceptibility to gentamicin, co-trimoxazole, erythromycin and clindamycin as compared to MRSA isolates. No isolate was found resistant to vancomycin or linezolid. Interpretation & conclusions: The study showed a high level of MRSA in our country. There is a need to study epidemiology of such infections. Robust antimicrobial stewardship and strengthened infection control measures are required to prevent spread and reduce emergence of resistance.

Characterization of nasopharyngeal isolates of type b Haemophilus influenzae from Delhi.

Background & objectives: Haemophilus influenzae is an important cause of mortality and morbidity among young children in developing countries. Increasing incidence of antibiotic resistance especially production of extended spectrum beta lactamase (ESBL) has made treatment and management of H. influenzae infection more difficult. Nasopharyngeal H. influenzae isolates are excellent surrogate for determination of antibiotic resistance prevalent among invasive H. influenzae isolates. In this study, we characterized nasopharyngeal H. influenzae isolates obtained from healthy school going children in Delhi. Methods: Nasopharyngeal H. influenzae isolates were collected from healthy school going children and subjected to serotyping, fimbrial typing and antibiogram profiling. ESBL production was recorded using phenotypic as well as molecular methods. Multi locus sequence typing (MLST) of 13 representative nasopharyngeal H. influenzae isolates was performed as per guidelines. Results: A significant proportion (26 of 80, 32.5%) of nasopharyngeal isolates of H. influenzae were identified as serotype b. Fimbrial gene (hifA) was detected in 23 (28.75%) isolates. Resistance against commonly prescribed antibiotics (Amp, Tet, Chloro, Septran, Cephalexin) were observed to be high among the nasopharyngeal commensal H. influenzae. Extended spectrum beta lactamase (ESBL) production was observed in a five (6.25%) isolates by both double disk diffusion and molecular typing. MLST identified several novel alleles as well as novel sequence types. Interpretation & conclusions: Our findings showed high resistance against common antibiotics and detection of ESBL in nasopharyngeal H. influenzae isolates collected from normal healthy school going children in Delhi. Detection of H. influenzae type b capsular gene and the presence of fimbrial gene (hif A) suggest virulence potential of these isolates. Discovery of novel alleles and presence of new sequence types (STs) among nasopharyngeal H. influenzae isolates may suggest wider genetic diversity.

A pilot study for diagnosis of genital Chlamydia trachomatis infections by polymerase chain reaction among symptomatic Indian women.

Background: Chlamydia trachomatis is the most common bacterial etiology of sexually transmitted infection. Aim : A pilot study was designed using PCR for amplification and detection of a specific 517 bp sequence of the common endogenous plasmid of C. trachomatis from clinical swab specimens obtained from symptomatic female patients attending STD clinics of AIIMS and Regional STD Teaching, Training & Research Center, Safdarjang Hospital, New Delhi. Methods: 97 patients were recruited in the study, and endocervical swabs were collected following standard procedures. The samples were analyzed by PCR and direct fluorescence antibody (DFA) for detection of C. trachomatis, and the sensitivity, specificity, PPV and NPV of PCR were calculated taking DFA as gold standard. Results: Out of 97 samples tested, 9 were positive for C. trachomatis by PCR. 1 PCR positive patient was negative by DFA although a total of 11 patients were positive by DFA. The sensitivity, specificity, PPV and NPV of PCR with reference to DFA was 72.73%, 98.84%, 88.89% and 96.59%, respectively. This PCR had high specificity and NPV for detection of C.trachomatis. Conclusions : In light of the introduction of enhanced syndromic approach, which involves the use of laboratory techniques (wherever possible) to confirm clinical diagnosis, a diagnostic PCR with high specificity and NPV is particularly valuable for determination of etiological diagnosis and hence contribute to judicious use of antimicrobials in the community.

Primary meningococcal polyarthritis in a young man.

We report a rare occurrence of primary meningococcal polyarthritis in a 19-year-old man. The fluid in the elbow joint showed Gram-negative diplococci but the culture was sterile. The diagnosis was confirmed by polymerase chain reaction targeting crgA gene of Neisseria meningitidis.