Semiquantitative Culture Research Articles

Density Distribution of Pharyngeal Carriage of Meningococcus in Healthy Young Adults: New Approaches to Studying the Epidemiology of Colonization and Vaccine Indirect Effects.

Improved understanding of Neisseria meningitidis (Nm) carriage biology and better methods for detection and quantification would facilitate studies of potential impact of new vaccines on colonization and transmission in adolescents. We performed plate cultures on 107 oropharyngeal swabs stored frozen in skim milk tryptone glucose glycerol (STGG) broth and previously positive for Nm. We compared quantitative polymerase chain reaction (qPCR) detection of Nm in 601 STGG-swabs with culture. Using qPCR (n = 87), a log-phase broth culture standard curve and semiquantitative plate cultures (n = 68), we measured density of carriage. We compared qPCR genogrouping of DNA extracts from STGG-swabs and from plate culture lawns (n = 110) with purified isolates (n = 80). Swab storage resulted in only 10% loss of culture sensitivity. Direct sodC qPCR Nm detection yielded more positives (87/601, 14.5%) than culture (80/601, 13.3%). Most samples (57/110) positive by culture were also positive by qPCR and vice versa, but discrepancies (single positives) were frequent among low-density samples. sodC qPCR was positive in 79/80 isolates but in only 65 by ctrA qPCR. Density both by culture and qPCR varied across 4 orders of magnitude with the majority being low (<50 bacteria-gene copies/mL) and a minority being high (>1000). Genogrouping qPCRs yielded more positive results when performed on DNA extracts from lawn cultures. We provide the first description of the distribution of Nm carriage density. This could be important for understanding transmission dynamics and population-level effectiveness of adolescent vaccine programs. Storage of swabs frozen in STGG for batched laboratory analysis facilitates carriage studies and direct sodC qPCR for Nm combined with qPCR genogrouping of lawn culture extracts provides accurate, detailed description of colonization.

Clinical features, cytology and bacterial culture results in dogs with and without cheilitis and comparison of three sampling techniques.

Cheilitis is a common presentation in dogs associated with a variety of skin diseases and often complicated by microbial infections. To describe and compare clinical and cytological features and bacterial culture results from the lower lips of dogs with cheilitis (as compared to healthy controls), and to evaluate three cytology sampling techniques for their abilities to differentiate between the groups. Fifty six dogs with cheilitis and 54 controls. Anatomy and clinical signs of the lower lip were recorded. Cytology samples taken by tape strip, direct impression and swabs rolled over skin were scored semiquantitatively for microorganisms, inflammatory cells and keratinocytes. Cytology scores were correlated with semiquantitative bacterial culture scores. Pure breeds, frequency of lip folds and all cytology scores except keratinocytes were higher in dogs with cheilitis than in controls, but a substantial overlap was seen in all microorganisms between the groups. Hypersensitivity disorders were diagnosed in 40 of 56 dogs with cheilitis. The tape strip technique yielded the greatest differences between groups. Bacterial growth was reported in 100% of dogs with cheilitis and in 93% of the controls. Pathogens such as Staphylococcus pseudintermedius, Escherichia coli and Pseudomonas spp were found more frequently in dogs with cheilitis. Cytology and bacterial culture were poorly correlated. Cheilitis was associated with primary hypersensitivity disorders and the presence of a lip fold was a predisposing factor. Results of aerobic culture were similar to prior studies on pyoderma of other body sites, except for higher rates of Pseudomonas spp. isolation.

Correlation between biofilm formation and resistance toward different commonly used antibiotics along with extended spectrum beta lactamase production in uropathogenic Escherichia coli isolated from the patients suspected of urinary tract infections visiting Shree Birendra Hospital, Chhauni, Kathmandu, Nepal.

BackgroundEscherichia coli is the most predominant causative agent of urinary tract infection (UTI). Recently, increase in drug resistance among the uropathogenic bacteria has caused great problem in treatment of UTI. The main objective of this research is to determine the correlation between biofilm formation and resistance toward different commonly used antibiotics along with extended spectrum beta lactamase production in uropathogenic Escherichia coli.MethodsThe urine samples collected from the patients suspected of urinary tract infections (visiting Shree Birendra Hospital, Chhauni, Kathmandu, Nepal between July to December 2013) were cultured in cystine lactose electrolyte deficient (CLED) agar by using semi quantitative culture technique. Extended spectrum beta lactamase (ESBL) production was detected by combined disc diffusion technique and biofilm formation was detected by Congo red agar method. Chi-square test was applied and p-value < 0.05 was considered statistically significant.ResultsOut of 1480 urine samples, E. Coli was isolated from 208 (14.1 %) samples. Of total 69 (33.2 %) ESBL producing uropathogenic strains of E. coli, 20 (29 %) were strong biofilm producers, 22 (31.9 %) were moderate biofilm producers, 11 (15.9 %) were weak biofilm producers and 16 (23.2 %) were biofilm non producers. Whereas among 139 ESBL non producing E. coli, 22 (15.8 %) were strong biofilm producers, 20 (14.4 %) were moderate biofilm producers, 13 (9.4 %) were weak biofilm producers and 84 (60.4 %) were biofilm non producers. Among total 108 biofilm producing E. coli, maximum resistance was observed toward cephalexin followed by amoxicillin and highest susceptibility was seen toward amikacin.ConclusionThe ability of biofilm formation was found to be significantly higher in ESBL producing strains of E. coli than that in ESBL non producing strains (p < 0.05). There was higher resistance rate to antimicrobial agents among biofilm producing strains of E. coli than that in biofilm non producing strains. According to our antimicrobial susceptibility pattern for E. coli, to start preliminary treatment for UTI in Nepal, we recommend to use amikacin or nitrofurantoin. Further, for the treatment of the UTI, the antibiotics should be selected on the basis of the urine culture and sensitivity report.

In situ diagnostic methods for catheter related bloodstream infection in burns patients: A pilot study

BackgroundOne of the most common and potentially fatal complications in critically ill burns patients is catheter related bloodstream infection (CR-BSI). Lack of in situ diagnostic techniques requires device removal if CR-BSI is suspected with 75–85% of catheters withdrawn unnecessarily. AimsTo assess the sensitivity, specificity and accuracy of two in situ diagnostic methods for CR-BSI in an adult ICU burns population: Differential Time to Positivity (DTP) and Semi-Quantitative Superficial Cultures (SQSC). MethodsBoth arterial (AC) and central venous (CVC) catheters were studied. On clinicians’ suspicion of CR-BSI, the CVC and AC were removed. Superficial semi-quantitative cultures were taken by removing the dressings and swabbing within a 3cm radius of the CVC and AC insertion sites, as well as inside each hub of the CVC and AC. Peripheral blood was taken for qualitative culture and the catheter tip sent for semi-quantitative culture. DTP was considered positive if culture of lumen blood became positive at least 120min before peripheral blood with an identical pathogen. Superficial and tip cultures were identified as positive if ≥15 CFUs were grown. CR-BSI was confirmed when both catheter tip culture and peripheral blood culture were positive with the same micro-organism. ResultsSixteen patients (88% male) with an APACHE II score of 22.0 (7.3) were enrolled. The mean age was 45.7 (16.9) years with mean total burn surface area 32.9 (19.4)%. Fifty percent had airway burns. ICU stay was 19.9 (11.1) days. All 16 survived ICU discharge with a hospital survival of 93%. There were 20 episodes of CR-BSI in these 16 patients. For these 20 episodes the exposure time (line days) was 113.15. The CR-BSI rate was 15.6 per 1000 catheter days (95% CI 1.9–56.4). For diagnosis of CR-BSI in either AC and CVC, SQSC had a sensitivity of 50% [95% CI 3–97], specificity 83.3% [95% CI 67–93], PPV 14.3 [95% CI 1–58], NPV 96.8 [95% CI 81–100], accuracy of 81.6% [95%CI 65–92] and diagnostic odds ratio 5.0 [95% CI 0.3–91.5]. To diagnose tip colonisation (>15CFU), sensitivity of SQSC was 75% [95% CI 22–99], specificity 88.2% [95%CI 72–96], PPV 42.7 [95% CI 12–80], NPV96.8% [95% CI 81–100], accuracy 86.8% [95% CI 71–95] and diagnostic odds ratio 22.5 [95% CI 1.9–271.9]. For combined DTP blood cultures, sensitivity for CR-BSI was 50% [95% CI 3–97], with specificity 97% [95% CI 82–100], PPV 50% [5% CI 3–97%], NPV 97% [95% CI 82–100], accuracy 94.3% 95% CI 79–99] and diagnostic odds ratio 32 [95% CI 1.1–970.8]. ConclusionBoth DTP and SQSC displayed high specificity, NPV and accuracy in a population of adult burns patients. These features may make these tests useful for ruling out CR-BSI in this patient group. This study was limited by a low number of events and further research is required.

Community Acquired Enterococcal Urinary Tract Infections and Antibiotic Resistance Profile in North India.

Background:Urinary tract infections (UTIs) remain a major problem both in hospitalized and outdoor patients. Multidrug-resistant enterococci are emerging as a major nosocomial pathogen with increasing frequency. However, the incidence of community-acquired enterococcal infections and species prevalent in India is not thoroughly investigated.Objectives:This study aims to estimate the burden of community-acquired UTIs seen at a tertiary care hospital and to identify the Enterococcus species isolated from these patients. The study also aims to determine the antibiotic susceptibility pattern with reference to high-level aminoglycosides and vancomycin.Materials and Methods:Semi-quantitative cultures from a total of 22,810 urine samples obtained from patients seen at various Outpatient Departments were analyzed. From them 115 nonduplicate isolates of enterococci were obtained as significant pure growth (>105 cfu/ml) and speciated. Antibiotic susceptibility was performed by Kirby–Bauer disc diffusion method. Vancomycin resistance screening was performed by the vancomycin screen agar method recommended by Clinical and Laboratory Standards Institute and confirmed by determination of minimum inhibitory concentration by agar dilution method.Results:Of 115 enterococcal isolates, 61 were identified as Enterococcus faecalis, 42 as Enterococcus faecium, 3 each as Enterococcus dispar, and Enterococcus pseudoavium. High-level gentamicin resistance (HLGR) was higher in E. faecium (47.6%) than E. faecalis (32.7%) and HLSR also showed the same pattern with 47.6% and 27.9% resistance, respectively. Vancomycin resistant enterococci accounted for 11.3% of the isolates, and out of them 53.8% were E. faecium by agar dilution method.Conclusion:High rate of resistance to antibiotics of penicillin group and aminoglycosides was observed in our tertiary care hospital even in community acquired UTIs. Hence, there is an urgent need for more rational and restricted use of antimicrobials.

Asymptomatic bacteriuria and associated host factors in Diabetic patients with special reference to UTI Chromagar

Introduction: To study the prevalence of asymptomatic bacteriuria (ASB) in diabetics compared to non-diabetics and to determine the associated host factors responsible for ASB in diabetics. Materials and Methods: 250 diabetics and 100 controls were enrolled in the study and were screened for ASB using semi-quantitative culture methods and UTIchrom agar. The samples were screened for glucosuria, ketonuria and pyuria. Results: ASB was more common in diabetics compared to non-diabetics(12.8% v/s 6% ) and the increase was more in female diabetics when compared to female non-diabetics(16% v/s 6.15%) whereas male counterparts did not show much difference from the non-diabetics (6.09% v/s 5.71%). There was significant influence of age, duration of diabetes, glucosuria, ketonuria, proteinuria and pyuria on the incidence of ASB in diabetics thus proving them as possible risk factors for development of ASB. E.coli was the most common organism found in both diabetic as well as non diabetic cases of ASB (40.6% and 57.14% respectively). The next frequent organisms were Klebsiella and Staphylococcus. The sensitivity pattern was similar in both the population with ASB. Culture on UTI CHROMagar yielded quicker results when compared to standard culture methods. Conclusion: ASB is almost 3 times more common in female diabetics compared to female non-diabetics whereas there is not much difference among the male counterparts. The risk factors for ASB in diabetics included age, longer duration of diabetes, poor glycaemic control and renal dysfunction indicated by proteinuria. Culture on UTI CHROMagar is an easy and faster means of identification of organisms.

Ventilator-associated pneumonia in intensive care units of a tertiary care hospital in Punjab

IntroductionHealth care associated infections from invasive medical devices in intensive care pose the highest risk prolonging the hospital stay and cost for the patients. Ventilator-associated pneumonia (VAP) is an important infection in mechanically ventilated patients. Due to increasing incidence of multidrug-resistant organisms in intensive care units (ICUs), early and correct diagnosis of VAP is an urgent challenge for an optimal antibiotic treatment. ObjectivesThe aim of this study was to assess the incidence, commonest pathogens, and resistance pattern of isolates of VAP in ICUs of a tertiary care hospital. Material and methodsA prospective study was performed over a period of six months, enrolling patients undergoing mechanical ventilation for >48h. Endotracheal aspirates and bronchoalveolar lavage samples were collected from patients suspected of VAP and semi-quantitative cultures were performed on all samples. VAP was diagnosed by m-CPIS score (≥6). ResultsA total of 2369 patients were admitted in ICUs, of which 979 patients were on ventilator assistance (4165 ventilator days). Out of these, 47 (4.8%) patients developed VAP and early onset VAP was seen in 66% cases. The VAP rate was 11.03/1000 ventilator days. The commonest pathogen was Acinetobacter spp. followed by Pseudomonas spp. and Klebsiella spp. Most of the Acinetobacter spp. were resistant to cephalosporins, ciprofloxacin, and showed maximum susceptibility to tigecycline and polymyxin B. ConclusionsThe early onset VAP was more and incidence was high in males. This study highlights the predominance of resistant Gram-negative pathogens in VAP cases.

The Gene Polymorphism of IL-17 G-152A is Associated with Increased Colonization of Streptococcus pneumoniae in Young Finnish Children.

Streptococcus pneumoniae is a common respiratory pathogen, and up to 50% of children acquire S. pneumoniae in their nasopharynx during the first 12 months of life. The cytokine interleukin-17A (IL-17A) plays an important role in host defense against extracellular bacterial pathogens. We investigated the effect of IL-17 G-152A polymorphism on pneumococcal colonization in children. Nasopharyngeal swabs and blood samples were collected from healthy Finnish children at 2.6 (N = 405), 13 (N = 198) and 24 (N = 176) months of age. Of them, 160 had both nasopharyngeal swabs and blood samples at each time point. The semiquantitative culture method was used for bacterial culture, Sequenom iPlex Gold System for IL-17A genotyping and Luminex 200 for serum IL-17A determination. The frequency of IL-17 G-152A genotypes G/G, G/A and A/A was 36%, 45% and 19% in 405 studied subjects, respectively. The colonization rates of S. pneumoniae increased from 10% at 2.6 months to 33% at 24 months of age. Significantly higher pneumococcal colonization was found in subjects with A/A genotype at 13 and 24 months of age compared with those of G/G (RR, 2.30; P = 0.02; RR, 1.91, P = 0.03). This genotype was associated with lower levels of serum IL-17A, and only 6% of subjects with A/A had detectable serum IL-17A compared with 75% and 33% of subjects with G/G and G/A (P < 0.001 and P < 0.01), respectively. Our results indicate that IL-17 G-152A is associated with increased colonization rate of S. pneumoniae in young children, suggesting that IL-17A plays an important role in protection against pneumococcal colonization.

Hydrogen Peroxide-Producing Lactobacilli Are Associated With Lower Levels of Vaginal Interleukin-1β, Independent of Bacterial Vaginosis.

The presence of hydrogen peroxide (H2O2)-producing lactobacilli in the vagina is associated with decreased rates of preterm birth and HIV acquisition. We hypothesize that this is due to immunomodulatory effects of these species. Concentrations of interleukin (IL)-1β, IL-6, IL-8, secretory leukocyte protease inhibitor, and human β-defensin 2 were quantified from vaginal swabs from 4 groups of women: women with and without bacterial vaginosis (BV) by Nugent score, further stratified by detection of H2O2-producing lactobacilli by semiquantitative culture. Ten quantitative polymerase chain reaction assays characterized the presence and quantity of select Lactobacillus and BV-associated species in each group. Levels of immune markers and bacteria were compared between the 4 groups using analysis of variance, Kruskal-Wallis, Mann-Whitney U, or χ tests. Swabs from 110 women from 4 groups were included: 26 had a normal Nugent score (BV-), and no H2O2-producing lactobacilli detected (H2O2-); 47 were BV-, H2O2+; 27 BV+, H2O2-; and 10 BV+, H2O2+. The groups were similar in age, marital status, and reproductive history, but not ethnicity: the BV-, H2O2- group had more white participants (P = 0.02). In women with and without BV, IL-1β was lower in the H2O2+ groups. Human β-defensin 2 was lowest in BV+ H2O2- women and highest in BV-, H2O2-. Secretory leukocyte protease inhibitor was lower in women with BV and did not differ by the presence of H2O2-producing lactobacilli. In regression analysis, higher quantities of Lactobacillus crispatus were associated with lower quantities of IL-1β. Detection and quantity of BV-associated species by quantitative polymerase chain reaction was significantly different between women with and without BV, but not between women with and without H2O2-producing lactobacilli within those groups. The presence of H2O2-producing lactobacilli is associated with lower levels of some vaginal proinflammatory cytokines, even in women with BV.

Direct detection of methicillin-resistant Staphylococcus aureus in sputum specimens from patients with hospital-associated pneumonia using a novel multilocus PCR assay.

Methicillin-resistant Staphylococcus aureus (MRSA) is a significant cause of hospital-associated pneumonia (HAP). The rapid identification of MRSA would be beneficial for early diagnosis. The study aimed to evaluate a multilocus, fluorescence-based PCR assay based on the detection of mecA and nuc genes for identification of S. aureusin lower respiratory tract (LRT) specimens. Sensitivity and specificity of the PCR assay were analyzed. Clinical evaluation for the assay was performed using LRT specimens from patients with HAP, and the sensitivity, specificity, positive and negative predictive values (PPV and NPV) were evaluated in comparison with semi-quantitative culture methods. The result showed the assay provided positive identification of all MRSA reference strains with a limit of detection for MRSA of 4 × 103 CFU/mL. Compared with semi-quantitative culture, the sensitivity, specificity, PPV and NPV were 100%, 89.6%, 75.0%, and 100%, respectively. A positive correlation between MRSA bacterial colonies and PCR copy number was found. The specificity and PPV reached 96.6% and 89.7% respectively, if the PCR copy number reached a definite positive threshold of 5.96 × 105. It suggested that this novel multilocus, fluorescence-based PCR assay proved to be a fast, sensitive and specific tool for direct detection of MRSA from LRT specimens.

Surveillance for lower airway pathogens in mechanically ventilated patients by metabolomic analysis of exhaled breath: a case-control study

BackgroundHealthcare associated infections, including ventilator associated pneumonia, are difficult to diagnose and treat, and are associated with significant morbidity, mortality and cost. We aimed to demonstrate proof of concept that...

Detection of Pyuria versus Bacteriuria in Suspected Patients of Urinary Tract Infection

Urinary tract infection (UTI) is one of the most important causes of mortality and morbidity in the world affecting all age groups across the life span. The aim of this study is to determine incidence of bacteriuria and its relation with pyuria in suspected urinary tract infection. This crosssectional-descriptive-analytical study was conducted in microbiology section of Kathmandu Hospital, Tripureshwor from May to August 2011. During this period, 412 midstream urine samples collected were investigated by microscopic examination of centrifuged urine sediment and conventional semi-quantitative culture technique. Out of 412 MSU samples, 120 (29.13%) were culture positive. The remaining 22 (18.33%) samples showed low count significant bacteriuria (i.e 104-105 CFU/ml) and 98(81.67%) showed significant bacteriuria (i.e. ≥ 105 CFU/ml). Among 88 urine samples with significant pyuria, only 74 (84.09%) showed culture positive. Out of 324 urine samples without significant pyuria, 46 (14.19%) urine samples showed culture positive result. Significant pyuria was found to have sensitivity of 61.67%, specificity of 95.21% and the test has 84.09% positive predictive value in detecting bacteriuria. Pyuria and bacteriuria may not always correlate in the suspected case of UTI.DOI: http://dx.doi.org/10.3126/njst.v15i1.12029Nepal Journal of Science and TechnologyVol. 15, No.1 (2014) 129-132

Usefulness of Sonication of Cardiovascular Implantable Electronic Devices to Enhance Microbial Detection

The cardiovascular implantable electronic device (CIED) infection rate is rising disproportionately to the rate of device implantation. Identification of microorganisms that cause CIED infections is not always achieved using present laboratory techniques. We conducted a prospective study to determine whether device vortexing-sonication followed by culture of the resulting sonicate fluid would enhance microbial detection compared with traditional swab or pocket tissue cultures. Forty-two subjects with noninfected and 35 with infected CIEDs were prospectively enrolled over 12 months. One swab each from the device pocket and device surface, pocket tissue, and the CIED were collected from each patient. Swabs and tissues were cultured using routine methods. The CIED was processed in Ringer's solution using vortexing-sonication and the resultant fluid semiquantitatively cultured. Tissue and swab growth was considered significant when colonies grew on ≥2 quadrants of the culture plate and device was considered significant when ≥20 colonies were isolated from 10 ml of sonicate fluid. In noninfected group, 5% of sonicate fluids yielded significant bacterial growth, compared with 5% of tissue cultures (p = 1.00) and 2% of both pocket and device swab cultures (p = 0.317 each). In infected group, significant bacterial growth was observed in 54% of sonicate fluids, significantly greater than the sensitivities of pocket swab (20%, p = 0.001), device swab (9%, p <0.001), or tissue (9%, p <0.001) culture. In conclusion, vortexing-sonication of CIEDs with semiquantitative culture of the resultant sonicate fluid results in a significant increase in the sensitivity of culture results, compared with swab or tissue cultures.

Community acquired urinary tract infection in pediatric age-group with changing trends of antibiotic resistance pattern over 3 years: a clinico-epidemiological study

Background: Assessment of the antimicrobial sensitivity pattern in urinary isolates of the children suffering from urinary tract infection (UTI) and evaluation of the recent trends of multi-drug resistance in the isolates. The aim was to find out the antibiotics sensitivity of the organisms isolated from the urine samples of pediatric age-group with emphasis on their resistance pattern. Methods: A clinico-epidemiological study comprising of 304 specimens of urine were collected among all the children with UTI below 12 years of age, attending pediatric outpatient department of a tertiary care teaching hospital in eastern India wet mount microscopy and semi quantitative culture were done to diagnose UTI. Organisms isolated were identified by standard biochemical tests, and antibiogram studies were done by standard Kirby-Bauer disc diffusion test statistical analysis, Microsoft excel and SPSS were used for analysis of data. Results: Aminoglycosides had wider sensitivity pattern toward most of the uropathogens whereas tetracyclines and co-amoxyclav in particular were resistant for most of the organisms. Among all the organisms, Pseudomonas and Enterococcus species showed higher resistance pattern toward the conventional antimicrobials. Conclusions: The changing trends in the anti-biograms of several Gram-positive and Gram-negative microorganisms in UTI demands reconsideration with respect to rational drug use in the pediatric age group.

Concordance between a new molecular real-time approach and traditional culture in suspected VAP patients

Early microbiological documentation may reduce attributable mortality and excessive use of broad-spectrum antibiotics in ventilator-associated pneumonia (VAP). Using bronchoalveolar lavage (BAL) and endotracheal aspirates (ETA), we studied a new molecular biology-based approach to detect and quantify bacteria in less than 3 hours. This prospective multicenter trial aimed at comparing the microbiological results obtained using this molecular protocol (easyMAG® system) and semiquantitative culture in suspected VAP.

Risk factors, pathogen profile and outcome of ventilator associated pneumonia in a Neonatal intensive care unit

Background: Objective of current study was to know the risk factors, pathological profile and outcome of ventilator associated pneumonia in the neonatal intensive care unit. Methods: Design: Prospective observational study. Settings: A teaching, referral, neonatal intensive care unit at Srinagar, Kashmir. Participants: All ventilated neonates who required mechanical ventilation for more than 48 hours between August 2011 to July 2012. Procedure : The diagnosis of VAP was made on the basis of criteria given by National Nosocomial Infection Surveillance System (1996), paediatric modification of the original guidelines given by Centre of Disease Control & prevention (CDC). Risk factors for VAP were assessed by bivariate and multivariate analysis. Semi-quantitative culture was done using blood agar, chocolate agar and McConkey’s agar as plating media. Results: VAP developed in 32 of 96 ventilated neonates (33.34% VAP rate). Prematurity, very low birth weight, use of nasogastric tube, mean duration of mechanical ventilation, NICU stay in days and number of endotracheal tube changes were statistically significant risk factors associated with VAP. Multiple logistic regression analysis revealed that duration of mechanical ventilation (P = 0.006) and VLBW (<15000 grams) (P = 0.032) were only two single independent and statistically significant risk factors. Most common bacteria isolated from ETA was Klebsiella (37.5%). There were 9 (28.1%) mortalities in VAP group and 14 (21.8%) in non-VAP group, which was statistically insignificant. Conclusions: A number of measures is required to decrease the incidence of VAP based on the prevalent modifiable risk factors and etiological organisms in NICU. Daily assessments of readiness to wean and use of weaning protocols must be adhered to in NICUs.

Prevalence of Urinary Tract Infections and Susceptibily Pattern of Uropathogens in Women of Reproductive age Group from North India

Urinary tract infections (UTI) are one of the most common infections causing morbidity in community and health care setup. Women in reproductive age group (15–49 yrs) are more prone to UTI. This study was undertaken to determine the prevalence of UTI, the microbial etiology and the antibiotic susceptibility profile of the isolates from women with symptomatic UTI in a tertiary care centre in north India. Clean catch midstream urine were processed by semi-quantitative culture and isolates identified by standard biochemical tests. Antibiotic sensitivity was performed by Kirby-Bauer disc diffusion test and data analyzed from January 2013 to September 2015. A total of 3141 cases were studied. Prevalence of UTI varied from 16.69% in 2013, 9.77% in 2014 to 8.45% in 2015. Majority of UTI occurred in the age group 21–30 yrs. E.coli was the commonest isolate causing UTI followed by E.faecalis. E.coli showed considerable resistance to ampicillin and fluoroquinolones but performed better against nitrofurantoin with greater than 90% susceptibility. Constant survey of uropathogens and their susceptibility profile is essential for deciding on the empirical treatment of UTI.

Utility of Urine Dipstick Test for the Screening of Urinary Tract Infection in Catheterized Women Following Gynecological Surgeries.

Our objective was to determine the utility of urine dipstick test for the screening of urinary tract infection in catheterized women following gynecological surgeries. This was a descriptive study carried out in a tertiary care centre. Five hundred post-operative women were enrolled in the study whose urine samples were collected under sterile precautions from their catheters and simultaneously subjected to the dipstick test at the bed side of the patient and submitted to the laboratory for semi-quantitative culture and microscopy. Data were expressed as proportion. The results of the culture, microscopic examination, and the dipstick test were analyzed using Chi-square test. When culture results were compared with the leukocyte esterase (LE) test and the nitrite reduction (NR) test, the P value obtained was <0.0001, respectively. Sensitivity was 88.24, 85.29, and 87.88%, respectively, for the LE test, NR test, and when both these tests were combined. The specificity for the LE test and the combination were, respectively, 98.46% while for the NR test was 96.71%. The positive predictive value decreased from 81.08 to 80.56% on combining the tests while the negative value remained unchanged at 99.11%. These bedside tests could considerably reduce the laboratory workload and allow important clinical decisions to be made early.

Comparison of screening tests with urine culture in urinary tract infection

Introduction: Urinary tract infection (UTI) is an important health care problem affecting millions every year. Evaluation of suspected UTI includes history, physical examination and laboratory investigations. Urine analysis for presence of pus cells, bacteria and culture are important in the adequate management of UTIs. Aim of the study was to analyze the screening tests with culture method in the diagnosis of UTI. Materials and methods: 100 turbid midstream urine specimens collected in a sterile wide mouthed container were included in the study. Mid-stream urine specimens collected from both inpatients and outpatients attending a tertiary care hospital were included in the study. Urine specimen was subjected to Gram’s staining and catalase tests and inoculated into culture medium. Semi-quantitative culture technique was followed. Organisms were identified for significant bacteriuria. Results: Samples collected from 40 years of age and from patients more than 40 years of age were 64% and 51% were male patients. Gram’s stain showed 59% of samples with organisms. Pus cells were seen in 54% of the smears and all the samples had significant growth in the medium Catalase positive was 53%, all the 53 strains had growth on culture plate. E. coli was the commonest organism isolated on the culture plate. Thus screening tests like Gram’s stain, pus cells detection and catalase test can be used as a rapid method to detect urinary tract infection and to start the antibiotic therapy though culture remains the gold standard method for detection of urinary tract infection. Keywords: Gram’s Staining, Pus Cells, Catalase Test, Culture Medium, Significant Bacteriuria.

PS-323 The Gene Polymorphism Of Il-17 G-152a Is Associated With Increased Colonisation Of Streptococcus Pneumoniae In Children

Background and aims Streptococcus pneumoniae is a common respiratory pathogen and up to 50% of children acquire S. pneumoniae in their nasopharynx during the first 12 months of life. The cytokine interleukin-17A (IL-17A) plays an important role in host defense against extracellular bacterial pathogens. We investigated the effect of IL-17 G-152A polymorphism on pneumococcal colonisation and the serum level of IL-17A in children. Methods Nasopharyngeal swabs (NP) and blood samples were collected from 412 Finnish children at 2.6 months. Of them, 160 had both NP and blood sample available at 12 and 24 months of age. The semi-quantitative culture method was used for bacterial culture, Sequenom iPlex Gold System for IL-17A genotyping and Luminex 200 for serum IL-17A determination. Results Of 160 subjects, 34% were G/G wild type, 45% G/A heterozygotes and 21% A/A homozygotes. The prevalence of S. pneumoniae in the same cohort of 160 subjects increased from 8% to 30% during the 2-year follow-up. Significantly higher pneumococcal colonisation was found in subjects with A/A genotype at both 12 and 24 months of age compared to those with G/G (p < 0.05 for both). Of 96 sera randomly selected from 160 subjects at 12 months, only 6% with A/A and 33% with G/A genotypes had detectable IL-17A compared to 75% with G/G (p < 0.001, p < 0.01). Conclusions Our data suggest that gene polymorphism of IL-17 G-152A is associated with increased colonisation of S. pneumoniae and that lower serum levels of IL-17A were observed in subjects with A/A and G/A genotypes of IL-17A.