Isolation of Enterococcus spp. in various clinical sample and their antimicrobial resistant pattern with MIC of vancomycin in patient attending tertiary care centre, RIMS, Ranchi, Jharkhand

Introduction- Enterococci are part of normal intestinal flora of humans and animals but have also emerged as important pathogens responsible for serious infections in hospital and community acquired infections.it is second most common cause of nosocomial infections in gastrointestinal tract, wound and genitourinary tract. To process all the clinicalAim- samples from various department in our hospital, for isolation of Enterococci spp. To speciate the isolates & to have resistance pattern of the isolates of vancomycin total 926 sample were collected from both outMaterial & Methods- patients and in patient in all clinical departments and transported to microbiology laboratory. specimens were processed by inoculating on to blood agar, MacConkey Agar, nutrient agar, potassium tellurite agar and incubated at 37°C for24-48 hr. Enterococci were identified by their typical arrangement in and salt tolerance test Gram stain, bile esculin test and biochemical tests. Antimicrobial susceptibility patterns were determined by performing Kirby-Bauer disc diffusion method and Minimum inhibitory concentration (MIC) values were identified by tube dilution methods. Result- a total of 926 sample, 645 (69.72%) were culture positive and 281 (30.28%) were culture negative. Among 645 culture positive cases, 81(12.55%) were Enterococcus faecalis. Antimicrobial susceptibility & MIC done as per standard protocols. The E. Faecalis showed 99% sensitive to Vancomycin. the resistance to vancomycin was 1% & further confirmed by MIC via tube dilution methods. In which MIC was ?32 ?g/ml in one isolate. About 8 of Enterococcal strains showed MIC of 0.0125?g/ml. species level identification of Enterococcus is important forConclusions- epidemiological study and also for analysis of drug resistant pattern. Effective detection of vancomycin resistance helps in reducing the morbidity and mortality of VRE in hospitalized patients

Microbial colonisation of orthopaedic tourniquets: A potential risk for surgical site infection.

Pneumatic tourniquets have been used in orthopaedic surgery to get avascular fi elds. Sixteen such tourniquets were analysed for microbial colonisation. Samples were taken from two inner and two outer areas of each tourniquet and cultured on sheep blood agar. Eight of these were wiped with Savlon and the rest with Sterillium solution. Post-treatment samples from the same sites were again cultured. After incubation, colonies from each site were identifi ed and counted. It was observed that the tourniquets were colonised with coagulase-negative staphylococci, Staphylococcus aureus, Bacillus, diphtheroids, Pseudomonas, Acinetobacter, enterococci, enterobacteria, and Candida. On treating with Savlon and Sterillium, there was 92.18% and 95.70% reduction in the colony count, respectively.

Evaluation of the Usefulness of MacConkey Agar and Colistin-Nalidixic Acid Blood Agar for Body Fluids, Peritoneal Fluid, and Wound/Abscess Specimens / 대한임상미생물학회지

BACKGROUND: Most clinical microbiology laboratories in Korea have difficulty in following the recommendations of the clinical procedure handbook for culture of body fluid and wound/abscess specimens. We evaluated the usefulness of MacConkey (MAC) and colistin-nalidixic acid blood agar (CNA) for the isolation of pathogens from these specimens. METHODS: A total of 1,508 clinical specimens [144 peritoneal fluid, 241 body fluids (19 bile, 70 joint fluid, 6 pericardial fluid, 104 pleural fluid, and other fluids in 42 cases) and 1,123 wound/abscess] were inoculated onto basic media [Blood agar plate (BAP), chocolate agar or BAP with streaking of Staphylococcus aureus] and simultaneously inoculated onto MAC and CNA. The pathogens isolated by basic media and by additional use of MAC and/or CNA were compared. RESULTS: With basic media, 885 isolates from 588 specimens were detected, and by additional use of MAC and CNA, an additional 27 isolates from 24 specimens and an additional 128 isolates from 112 specimens were isolated, respectively. Compared to the basic media, by adding MAC, an additional 233.3%, 38.5% and 4.5% of gram-negative bacteria were isolated from peritoneal fluids, body fluid and wound/abscess, respectively, and by adding CNA, an additional 106.7%, 45.0%, and 20.7% of gram-positive bacteria/ yeast were isolated, respectively. The isolates detected by additional use of MAC were mainly Enterobacteriaceae (77.0%), and those detected by CNA were S. aureus (21.1%), Coagulase-negative Staphylococcus spp. (20.3%), Enterococcus spp. (16.4%), Streptococcus spp. (10.2%) and yeasts (16.4%). CONCLUSION: For peritoneal fluid and body fluid specimens, additional use of MAC plus CNA seems necessary for detection of pathogens. For wound/abscess, additional use of CNA will be cost effective.

Isolation of Campylobacter from human stool samples.

Context: Campylobacter is an undetected cause of diarrhoea especially under 5 years of age in most of the countries. Isolation of this organism is diffi cult, expensive and cumbersome. Aims: Our objective of this study was to isolate this pathogen from the stool specimens on routinely available blood containing laboratory media using the candle jar for creating the microaerophilic atmosphere in our setup. Settings and Designs: A descriptive study. Materials and Methods: A total of 50 stool samples were inoculated onto selective and non-selective media with and without fi ltration using a 0.45 μm membrane. The inoculated media were simultaneously incubated in microaerophilic conditions using the Anoxomat as well as in candle jars at temperatures 37°C and 42°C. The culture isolates were confi rmed by standard phenotypic tests. A simplex polymerase chain reaction (PCR) targeting the 16S ribosomal deoxyribonucleic acid of Campylobacter was performed on the deoxyribonucleic acid (DNA) of the culture isolates as well as on the DNA extracted from the stool fi ltrates. Statistical Analysis: Data was expressed as a proportion. Results: Campylobacter could be isolated in 5 out of 50 stool samples using both the Anoxomat as well as the candle jar. Furthermore, we did not fi nd any difference between the isolation using the selective and blood containing media as well as the different incubation temperatures. All the fi ve were confi rmed phenotypically and genotypically to be Campylobacter jejuni. The PCR results corroborated with that of the culture. Conclusions: Isolation by culture was as sensitive as that of the PCR.

Neonatal sepsis due to Weeksella virosa.

Weeksella virosa was previously included in group II f of CDC. We here present the Microbiological characteristics of the isolate from a case of neonatal sepsis at our center. The organism is a non-fermenter growing only on blood agar and not on Mac Conkey agar, oxidase and catalase positive, and negative for several other bio-chemical tests, except for indole with Ehrlich’s reagent. The isolate in the present case study was sensitive to aminoglycosides and β- lactams, and resistant to quinolones and carbapenems.

A rapid detection of multidrug-resistant Mycobacterium tuberculosis by a nitrate reductase assay on blood agar

The susceptibility of 49 Mycobacterium tuberculosis clinical isolates to isoniazid (INH) and rifampisin (RIF) (28 multi-drug resistant-tuberculosis samples) was determined by a nitrate reductase assay (NRA) on blood agar. Agreement between the NRA and other testing methods was found to be 93.8 percent for both INH and RIF. The sensitivity, specificity, positive predictive value and negative predictive value for INH were 92.8 percent, 94.2 percent, 86.6 percent and 97 percent, respectively. The sensitivity, specificity, positive predictive value and negative predictive value for RIF were 90.4 percent, 96.4 percent, 95 percent and 93.1 percent. In conclusion, we show here that blood agar can be used effectively for the NRA test.

Is inclusion of Sabouraud dextrose agar essential for the laboratory diagnosis of fungal keratitis.

Purpose: To determine whether the inclusion of Sabouraud dextrose agar (SDA) is essential in the diagnosis of fungal keratitis. Materials and Methods: Corneal scrapings of 141 patients with microbial keratitis were smeared and cultured. Sheep blood agar (BA), chocolate agar (CA), SDA, non-nutrient agar (NNA) with Escherichia coli overlay, and brain heart infusion broth (BHI) were evaluated for time taken for growth and cost. The media were also evaluated experimentally for rate of growth and time taken for identification. Results: Twenty-six of 39 patients positive for fungus in corneal scrapings by microscopy were culture-positive. Fungus grew on BA in 22/39, on CA in 18/39, on SDA in 17/39, on NNA in 17/39, and on BHI in 13/39 cases. Growth on SDA was higher in ulcers with larger infiltrate (6/18 versus 9/13, P = 0.04). Estimated saving with inclusion of only BA/CA was Rs. 600 per patient. Performance of all media was similar in in vitro experiment although the characteristic spores and color were seen earlier on SDA. Conclusion: Fungal keratitis can be reliably confirmed on BA or CA, which support growth of both bacteria and fungus.

Comparación de medios de cultivos y procedimientos para detectar colonización por Streptococcus agalactiae en mujeres embarazadas / Comparison between culture media and procedures to detect Streptococcus agalactiae in pregnant women

Introducción: La detección de Streptococcus agalactiae en la vagina y/o el recto de las mujeres embarazadas y la administración de profilaxis antimicrobiana intraparto en las colonizadas, es el método recomendado para prevenir la infección neonatal precoz por este patógeno. En consecuencia, es importante seleccionar los medios de cultivos y el sitio de toma de muestra más adecuado para la detección de S. agalactiae en mujeres colonizadas. Objetivo: Comparar diferentes medios de cultivos y procedimientos para la recuperación de S. agalactiae en mujeres embarazadas con complicaciones gineco-obstétricas. Metodología: Se tomaron hisopados vagino-ano-rectales y endocer-vicales de 60 mujeres embarazadas. Con la primera muestra se realizó cultivo directo en agar sangre Columbia selectivo (ASCSD), y caldo selectivo Todd Hewitt (CSTH) incubados a 37 °C, y subcultivos a las 4 y 18 horas en agar sangre Columbia selectivo (ASCS). La segunda muestra se cultivó en ASCS. El ASCSD y ASCS se incubaron en atmósfera microaeróñla a 37 °C durante 24 a 48 horas. La identificación de S. agalactiae se realizó mediante pruebas convencionales. Resultados: Utilizando hisopado vagino-ano-rectal se detectaron 21 pacientes colonizadas con S. agalactiae, de la siguiente manera: 19(31,7 por ciento) en el ASCSD, 21 (35 por ciento) en el CSTH a las 4 horas y 20 (33,3 por ciento) a las 18 horas. De las 21 pacientes colonizadas sólo a una paciente se le detectó S. agalactiae en la muestra de secreción vagino-ano-rectal y endocervical simultáneamente. Conclusión: Los tres procedimientos ensayados presentaron igual efectividad para la recuperación de S. agalactiae; sin embargo, con el uso del ASCSD, se disminuyen los costos y el tiempo de identificación de dicho microorganismo. Por otra parte, el hisopado vagino-ano-rectal resultó ser la muestra más idónea para detectar colonización por S. agalactiae en mujeres embarazadas.

Detection of Streptococcus agalactiae in pregnant women's vagina and rectum and intrapartum antibiotic prophylaxis administered to colonized women are currently recommended to prevent neonatal precocious infections by this organism. In turn, it is very important to select the culture media and adequate sample collection site for S. agalactiae detection in colonized women. To standardize this methods in laboratory, different culture media and procedures for S. agalactiae recovery in pregnant women with obstetric and gynecologic complications were compared. Vaginorectal and endocervical swab specimens were collected from 60 pregnant women. The first sample was placed onto selective Columbia blood agar directly and onto selective Todd-Hewitt broth incubated at 37 °C and subcultured onto selective Columbia blood agar at 4 and 18 hours. The second sample was cultured on selective Columbia blood agar. Both culture media were incubated in a microaerophilic atmosphere at 37 °C from 24 to 48 hours. S. agalactiae was identified using conventional tests. 21 patients colonized with S. agalactiae were detected using vaginoanorectal samples. 19 (31.7 percent) patients tested positive for S. agalactiae through the culture of specimens directly onto selective Columbia blood agar; 21 (35 percent) and 20 (33 percent) patients were found to be positive for S. agalactiae by the selective Todd-Hewitt broth at 4 and 18 hours, respectively. Only one patient tested positive for S. agalactiae in the endocervical tract. The results show that the three procedures followed for S. agalactiae recovery are effective. Nevertheless, the procedure in which the sample was placed directly onto selective Columbia blood agar permits reducing costs and the time for bacteria identification. On the other hand, the vaginoanorectal swab was the best sample to detect colonization by S. agalactiae in pregnant women.

A Study for Improvement of the Positive Culture Rate Using Skin Biopsy Specimens in Patients with Cellulitis / 대한피부과학회지

BACKGROUND: Staphylococcus aureus and group A streptococci are the most common etiologic agents in cellulitis, but occasionally many other bacteria are also identified. The positive rate of bacterial cultures taken from the skin lesion are low. OBJECTIVE: This study aims to improve the positive culture rate in patients with cellulitis by using skin biopsy specimens in several kinds of media. METHODS: Skin biopsy specimens taken from 54 patients with cellulitis were cultured in 4 functionally-different types of media (blood agar, MacConkey agar, chocolate agar, thioglycollate broth). Positive culture rates were evaluated in each medium and cultured bacteria were identified. Clinical characteristics were also studied, including age, sex, affected site, and history of previous treatment. RESULTS: The sex ratio of males to females was 2.9: 1 and mean age was 49 years. The most commonly-involved site was the lower extremities (42.6%), followed by the upper extremities (13.0%), head and neck (9.3%), and trunk (1.9%). Patients who had received previous antimicrobial treatment numbered 31 cases (57.4%). Of the 23 patients who had received no previous antimicrobial treatment, 13 patients (56.5%) had positive cultures. The most common pathogens were S. aureus and Streptococcus sp. (59.1%), but seven different genus of bacteria were also isolated from 9 patients (40.9%). Thioglycollate broth yielded a high positive culture rate (38.9%) among the 4 types of culture media. CONCLUSION: It is suggested that the bacterial culture of skin biopsy tissue from four functionally-different types of media is a useful method for improving positive bacterial culture rate in patients with cellulitis.

PRELIMINARY STUDY ON THE CULTURE CHARACTERISTICS OF CAMPYLOBACTER PYLORIDIS / 重庆医科大学学报

In the experiments, various media were used to isolate Campylobacter Pyloridis. Onto every medium serum, blood, vitamin, glucose, charcoal and starch were added separately. The results were compared with direct Gram's stain method and urease test. Better growth was obtained on the brain-heart blood agar; almost no. growth occured on the serum agar, normal blood agar and C. jejuni agar. The positive rate was increased after charcoal and starch were added. The positive rate was significantly increased after vitamin and glucose were added. The colonies were increased significantly. It was similar with the results of the direct Gram's stain method