Chromogenic Agar Medium Research Articles

Molecular Analysis of Some Virulence Genes of Escherichia Coli Isolates from Wound and Burn Samples in Kirkuk City

Background: Gram-negative infections caused by non-spore producing E. coli that are facultatively anaerobic have been recognized as serious infections linked to higher mortality and significant costs associated with medical care.
 Aim: The goal of this study was to determine whether or not a number of E. coli strains are capable of producing virulence genes by using a technique called real time PCR.
 Materials and Methods: 155 people with burns and wounds had their cultures obtained, and susceptibility testing using swabs, tissue biopsies, and needle aspirations were performed. When compared to other techniques of specimen collection, swab cultures yield precise results and are a practicable, widely utilized, non-invasive, and cost-effective method. The two most recommended techniques for obtaining specimens are tissue biopsy and needle aspiration. Swab cultures, on the other hand, are appropriate since they are useful, widely applied, non-invasive, and reasonably priced. Samples from patients were collected in the consultation rooms, including swabs from burns and wounds. The sufferers had these taken from them. Before being identified, smear samples were initially cultivated in the lab on several selective media. Transport media-filled sterile collection containers containing these samples were brought to the lab.
 Results: According to the study's findings, E. coli was found in 27.10% of the burns and wounds samples. According to the study's findings, the majority of patients with E. coli infections (71.43 percent) were females, while only 28.57 percent were males. According to the study's findings, 28.57 percent of patients diagnosed with E. coli infections were between the ages of 31 and 40. The investigation also indicated that all of the sputum samples containing E. coli isolates were from patients above the age of 40. Furthermore, 45 percent of urine samples were collected from patients aged 31 to 40, and 42.86 percent of patients had wound infections. When examined using the MTP technique, fifty percent of the E. coli isolates tested positive for being potent biofilm producers, according to the study's findings. The DNA of 12 distinct E. coli bacterial isolates was isolated and purified using a genomic DNA purification kit. The bacteria were cultured on chromogenic agar medium to produce these E. coli isolates. The results were detected using electrophoresis on agarose gel at a concentration of 1.5 percent. The gel was then exposed to ultraviolet light, which revealed the DNA as compact bands. The virulence gene was found in 95.24 percent of the E. coli isolates taken from burn and wound sites, according to the study's findings. The majority of E. coli isolates tested positive for amikacin, imipenem, and gentamycin, according to the study's findings. The majority of E. coli isolates, on the other hand, were resistant to the medications amoxicillin, levofloxacin, cefotaxime, ceftriaxone, pefloxacin, cefepime, and ampicillin.

Rapid and automated screening of carbapenemase- and ESBL-producing Gram-negative bacteria from rectal swabs using chromogenic agar media and the ScanStation device.

The ScanSation 100 device (Interscience, France) is an incubator allowing real-time detection of bacterial colony growth by frequently imaging agar plates over time, counting CFU, and detecting colony color. This study evaluated its performance for the early detection of carbapenemase-producing bacteria (CPB) and extended-spectrum β-Lactamase-producing bacteria (ESBL-PB) from rectal swabs inoculated on CHROMagar mSuperCARBA and ESBL media, respectively. Rectal screening ESwabs collected from patients admitted to Grenoble University Hospital between January and June 2021 were analyzed. After inoculation, chromogenic media were incubated for 24 h in the automaton, with image acquisition every 30 min. ScanStation results were compared to visual observations of the plates after 24 h of incubation. In total, 501 rectal swabs were tested. ScanStation showed 100% positive percent agreement (PPA) for the detection of CPB and ESBL-PB, whereas the PPA of color categorization ranged between 45% and 100%. Negative percent agreement (NPA) ranged between 70% and 98%. Negative predictive values (NPVs) were 100% for both bacterial groups, whereas positive predictive values (PPVs) were 70.3% for CPB and 81.0% for ESBL-PB. Importantly, real-time screening allowed detection of the first suspected colony within 10-14 h of growth, on average, whereas visual observation is usually only performed once a day after 18-24 h of incubation. Our study demonstrates the potential use of early images to accelerate the detection of CPB and ESBL-PB and implement effective and timely infection control measures. IMPORTANCE The ScanStation 100 device is an incubator able to follow the real-time growth of bacterial colonies on agar plates through digital imaging, allowing users to sort plates according to the presence or absence of colonies, and to distinguish their color using four numeric color filters. Real-time screening shows that first colony detection is possible much earlier (after 10-14 h of growth, on average), whereas visual observation is usually performed only once a day after 18-24 h of incubation. The ScanStation device, combined with chromogenic agar media, is an efficient automated screening method to accelerate the detection of Gram-negative multidrug-resistant bacteria in laboratories that do not have access to larger laboratory automation systems. Our study shows that setting the image acquisition to one or two early images may allow for the detection of positive samples that were inoculated in the morning, by the end of the working day.

Morphology and molecular identification of Candida Species isolated from oral pediatric

In newborns, Candida is responsible for the common oral thrush and rash in skin folds and in the diaper area. Before the advent of modern sanitary measures and topical antifungal treatments, infants died from dehydration due to severe oral mucocandidiasis. Oral thrush is more likely to occur in infants and older adults due to reduced immunity. The study aimed to shed light on the relationship between Thrush and Candidia and To molecular identification of Candidia spp. isolated from Thrush. There are 100 samples of Oral swabs collected from pediatric with Thrush at ages ranging from (1day-12 years). All samples cultured on SDA, MSA and MEA. Several tests were used to identify the types of isolated yeasts, including growth on Chromogenic agar medium, as well as biochemical and molecular tests using primers ITS1, ITS4. The Results found that a six species of Candida were isolated on Chromogenic: C. albicans, C. glabrata, C. tropicalis, C. dubliniensis, C. krusei and C. kefyr, Also, showed the number of yeasts that were genetically diagnosed by molecular diagnosis was five species of yeasts as follows 2 isolates C. tropicalis from 22% and one isolate for each of the following types C. albicans, C. kefyr, C. dubliniensis and C. spp with 11% of all isolates where C. albicans showed the highest percentage. The results of the statistical analysis of the isolates showed that the most affected age group of pediatric was (month-1 year) in the rate of 24%. Antifungal susceptibility was studied, as the results indicated that all Candida isolates were sensitive to itraconazole, while all Candida isolates were resistant to fluconazole Furthermore, most types of Candida were resistant to Nystatin and Amphotericin B, except for three type’s C. krusei, C. glabrata, and C. kefyr. The most common pathogen in pediatric is Candida spp. In pediatric, the results indicated that the best treatment to eliminate Candida Itraconazol, Clotrimazol, Nystatin, and Amphotricine B Nystatin respectively

Evaluation of the morphological characteristics of Candida species on chromogenic agar medium and media for chlamydospore production

Background: Candida is a widespread pathogen with various clinical forms. By testing chlamydospore production and culturing on chromogenic agar, C. albicans and some species of C. non-albicans could be identified. Objectives: 1. To study the morphological characteristics of Candida species on Brilliance Candida agar and chlamydospore production media; 2. To evaluate the Candida species identification value of Brilliance Candida agar and chlamydospore production media. Materials and methods: 75 Candida isolates belonging to five species were identified by MALDI-TOF MS and stored. These isolates were cultured on Brilliance Candida agar and chlamydospore production media. Results: On Brilliance Candida agar: 100% of C. albicans isolates grew well and had green colonies after 24 hours, 100% of C. tropicalis isolates grew well and had blue color colonies after 48 hours; isolates of C. krusei, C. parapsilosis, and C. glabrata had different coloured colonies after 12 - 48 hours. In addition, C. krusei colonies were dry and wrinkled, compared to the other species’colonies, which were creamy, soft, and convex. 83-100% of C. albicans isolates produced chlamydospores after 3 days. The specificity of the Brilliance Candida agar culture and chlamydospore production test was 100% in identifying C. albicans. The sensitivity of Chromogenic Agar was 100% for C. albicans identification and 83%-100% for chlamydospore production after 3 days. The specificity and sensitivity of Chromogenic Agar in identifying C. tropicalis was 100% after 48 hours. Conclusions: Brilliance Candida agar had high specificity and sensitivity in identifying C. albicans after 24 hours and C. tropicalis after 48 hours. Chlamydospore production test had high specificity and sensitivity in identifying C. albicans at 3 days Key words: Candida, chromogenic agar, chlamydospore

Risk factors and molecular epidemiology of fecal carriage of carbapenem resistant Enterobacteriaceae in patients with liver disease

BackgroundCarbapenem resistant Enterobacteriaceae (CRE) colonization is a risk factor for CRE infection. CRE infection results in an increase in mortality in patients with cirrhosis. However, minimal data regarding the prevalence and the risk factors of CRE colonization in patients with liver disease yet without liver transplantation are available. The present study aimed to investigate the prevalence, risk factors and molecular epidemiology characteristics of CRE fecal carriage among patients with liver disease.MethodsStool specimens from 574 adult inpatients with liver disease were collected from December 2020 to April 2021. CRE were screened using selective chromogenic agar medium and identified by the Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined using the broth microdilution method. Carbapenemase genes were characterized by polymerase chain reaction (PCR) and DNA sequencing. Multilocus sequence typing (MLST) was performed for Carbapenem Resistant Klebsiella pneumoniae (CR-KPN) isolates and Carbapenem Resistant Escherichia Coli (CR-ECO) isolates.ResultsThe total number of stool specimens (732) were collected from 574 patients with liver disease. 43 non-duplicated CRE strains were isolated from 39 patients with a carriage rate of 6.79% (39/574). The carriage rate was 15.60% (17/109) in patients with acute-on-chronic liver failure (ACLF). Multivariate analysis indicated that ACLF (P = 0.018), the history of pulmonary infection within past 3 months (P = 0.001) and the use of third generation cephalosporin/β-lactamases inhibitor within past 3 months (P = 0.000) were independent risk factors of CRE colonization in patients with liver disease. Klebsiella Pnuemoniae (KPN) (51.28%) and Escherichia coli (ECO) (30.77%) were main strains in these patients. All CRE strains showed high resistance to most antimicrobials except for polymyxin B and tigecycline. Most (83.72%, 36/43) of the CRE carried carbapenemase genes. blaKPC-2 was the major carbapenemase gene. The molecular epidemiology of KPN were dominated by ST11, while the STs of ECO were scattered.ConclusionsThe present study revealed that CRE fecal carriage rates were higher in patients with ACLF than in patients without liver failure. ACLF, the history of pulmonary infection within past 3 months and the use of third generation cephalosporin/β-lactamases inhibitor within past 3 months were independent risk factors of CRE colonization in patients with liver disease. Regular CRE screening for hospitalized patients with liver disease should be conducted to limit the spread of CRE strain.

Conventional and Molecular Identification of Candida spp. And Antifungals Susceptibility Test in Pregnant Women

Candida species are medically significant because they are the most frequent opportunistic mycosis in the worldwide. Because of hormonal and biochemical fluctuations, Fungal infections in the vagina are tenfold during pregnancy. Increased antibiotic usage and the presence of high levels of reproductive hormones during pregnancy both promote Candida species colonization. The study aimed to shed light on the relationship between Urinary tract infection UTI and candidiasis and determines the genetic patterns and their prevalence among women. There are 90 samples of urine and vaginal swabs collected from pregnant women with UTI at ages ranging from (15-40) years. All samples cultured on SDA, MSA and MEA. Several tests were used to identify the types of isolated yeasts, including growth on Chromogenic agar medium, as well as biochemical and molecular tests using primers ITS1, 4. The Results found that a nine species of Candida were isolated on Chromogenic: C. albicans, C. glabrata, C. tropicalis, C. dubliniensis, C. parapsilosis, C. krusei, C. kefyr, C. membranifaciens and C. utilis, Also, showed the number of yeasts that were genetically diagnosed by molecular diagnosis was eight species of yeasts as follows 3 isolates C. albicans from 33% and one isolate for each of the following types C. orthopsilosis, C. glabrata, C. tropicalis, C. dubliniensis and C. parapsilosis with 11% of all isolates where C. albicans showed the highest percentage. The results of the statistical analysis of the isolates showed that the most affected age group of pregnant women was (26-30), (21-25 year) in the rate of 33%, 30% respectively. Antifungal susceptibility was studied, as the results indicated that all Candida isolates were sensitive to Miconazole and itraconazole, except for Candida albicans, which was resistant to itraconazole. Furthermore, most types of Candida Were resistant to Nystatin and Amphotericin B, except for three type’s C. krusei, C. tropicalis, and C. utilis. The most common pathogen in Urinary tract system is Candida spp. in pregnant women, the results indicated that the best treatment to eliminate Candida Miconazole,Itraconazol, Clotrimazol, Co-Trimoxazol, Ketoconazole, Fluconazole, Amphotricine B , and Nystatin respectively.

Effect of potassium tellurite concentration in a chromogenic agar medium on isolation of tellurite-resistant “Top Seven” Shiga toxin-producing Escherichia coli from ground beef

The effect of potassium tellurite concentration in a chromogenic agar medium on the detection of tellurite-resistant “top seven” Shiga toxin-producing Escherichia coli (STEC) in beef was evaluated. Samples of ground beef were inoculated with tellurite-resistant STEC O26, O45, O103, O111, O121, O145, or O157 strains at geometric mean (±standard error of the mean) levels of 0, 49 (±1), 490 (±1), or 4900 (±1) CFU/10 g and enriched 1:10 (90 mL) in EC broth (40°C for 6 h). Following enrichment, aliquots of broth culture were treated by immunomagnetic separation with one of three pools of beads against STEC serogroups; pool I: O26, O45, and O121; pool II: O103, O111, and O145; and pool III: O157. After immunomagnetic separation, 50 μL of washed bead suspensions in buffered peptone water was spiral plated onto a modified Possé medium containing 0.5, 1.0, or 1.5 mg/L potassium tellurite, and incubated at 37°C for 18 h. Up to four isolated colonies were picked from each spiral plate based on expected colony phenotypes for STEC, and isolate identity was confirmed with an 11-plex PCR assay targeting the O serogroups and virulence genes. Overall, across all inoculum levels and strains, modified Possé media containing 0.5, 1.0, or 1.5 mg/L potassium tellurite each had a positive predictive value of 100%, and medium containing 0.5 mg/L potassium tellurite had numerically the highest sensitivity (100%) and negative predictive value (100%), which was significantly different from 1.5 mg/L (92.9% and 40.0%, respectively; P < 0.05). Similarly, there was an inverse relationship between potassium tellurite concentration and analytical specificity (number of colonies tested that were STEC-positive): 0.5 (1463 of 1482; 98.7%), 1.0 (1356 of 1411; 96.1%), and 1.5 mg/L (1187 of 1278; 92.9%; P < 0.05). These results suggest that 0.5 mg/L gives better performance than 1.0 or 1.5 mg/L of potassium tellurite in Possé medium for isolation of tellurite-resistant “top seven” STEC from ground beef.

Evaluation of chromogenic agar medium, can it be a suitable alternative to conventional culture system for identification of uropathogens?

Urinary tract infections (UTI) account for major proportion of outpatient load and hospital admission globally. In most of the clinical microbiology laboratories MacConkey agar (MAC) and Cystine lactose electrolyte-deficient (CLED) agar are being used for identification of uropathogens. The main objective of the present study was to evaluate the usefulness of HiCromeTM UTI by comparing isolation rate and presumptive identification of uropathogens against CLED and MAC agar. This study was conducted over a period of three months on 672 non-duplicate midstream and/or catheter-catch urine samples. All samples were inoculated on to HiCromeTM UTI, CLED agar and MacConkey agar. Among the 672 samples received for culture, 113 (16.8%) showed significant growth. Among the 672 samples, 95 (14.1%) showed growth of a single organism while 18 (2.7%) showed polymicrobial growth. The rate of isolation and presumptive identification of the isolates and polymicrobial growth was found significantly higher on HiCromeTM UTI Agar. HiCromeTM UTI Agar has the potential to streamline processing of samples for urine culture in a way that will reduce the workload for technicians, reduce turnaround time which in turn will benefit the laboratory ultimately leading to better patient care.

Improved isolation and detection of toxigenic Vibrio parahaemolyticus from coastal water in Saudi Arabia using immunomagnetic enrichment.

BackgroundVibrio parahaemolyticus is recognized globally as a cause of foodborne gastroenteritis and its widely disseminated in marine and coastal environment throughout the world. The main aim of this study was conducted to investigate the presence of toxigenic V. parahaemolyticus in costal water in the Eastern Province of Saudi Arabia by using immunomagnetic separation (IMS) in combination with chromogenic Vibrio agar medium and PCR targeting toxR gene of species level and virulence genes.MethodsA total of 192 seawater samples were collected from five locations and enriched in alkaline peptone water (APW) broth. One-milliliter portion from enriched samples in APW were mixed with an immunomagnetic beads (IMB) coated with specific antibodies against V. parahaemolyticus polyvalent K antisera and separated beads with captured bacteria streaked on thiosulfate citrate bile salts sucrose (TCBS) agar and CHROMagar Vibrio (CaV) medium.ResultsOf the 192 examined seawater samples, 38 (19.8%) and 44 (22.9%) were positive for V. parahaemolyticus, producing green and mauve colonies on TCBS agar and CaV medium, respectively. Among 120 isolates of V. parahaemolyticus isolated in this study, 3 (2.5%) and 26 (21.7%) isolates of V. parahaemolyticus isolated without and with IMB treatment tested positive for the toxin regulatory (toxR) gene, respectively. Screening of the confirmed toxR gene-positive isolates revealed that 21 (17.5%) and 3 (2.5%) were positive for the thermostable direct hemolysin (tdh) encoding gene in strains isolated with IMB and without IMB treatment, respectively. None of the V. parahaemolyticus strains tested positive for the thermostable related hemolysin (trh) gene. In this study, we found that the CaV medium has no advantage over TCBS agar if IMB concentration treatment is used during secondary enrichment steps of environmental samples. The enterobacterial repetitive intergenic consensus (ERIC)-PCR DNA fingerprinting analysis revealed high genomic diversity, and 18 strains of V. parahaemolyticus were grouped and identified into four identical ERIC clonal group patterns.ConclusionsThe presented study reports the first detection of tdh producing V. parahaemolyticus in coastal water in the Eastern Province of Saudi Arabia.

Favorable Outcome in Patients with Pre-Transplant Gut Colonization with Intrinsically Vancomycin-Resistant Enterococci

IntroductionGut colonization with vancomycin-resistantenterococci (VRE) (specifically, Enterococcus faecium and E. fecalis) is common both before and after allogeneic hematopoietic cell transplantation (allo-HCT), and has been variably associated with VRE bloodstream infections. Clinical infections with intrinsically low-level VRE(E. gallinarum and E. casseliflavus), which have the chromosomally encoded vanC gene, are rare. Additionally, the clinical impact of pre-HCT gut colonization with these bacteria is unknown. In this study, we evaluated the outcome significance of pre-HCT colonization with E. gallinarum and E. casseliflavus, collectively named “intrinsics” herein.MethodsWe retrospectively reviewed the medical records of all adult and pediatric (>1 year old) allo-HCT recipients with available pre-HCT rectal swab or stool culture results at our institution (2011-2017). Second transplant recipients were excluded. SpectraTM VRE chromogenic agar medium (ThermoFisher Scientific) was used for species-level identification, and vancomycin E-test was used for MIC determination. Cases with ≥1 positive pre-HCT result for E. gallinarum or E. casseliflavus and no positive test for VRE or vancomycin-intermediate enterococci (VIE) were defined as intrinsics. Patients with no previous positive test for intrinsics or VRE/VIE, and with at least 2 negative tests for all these, were defined as controls. Due to the rare occurrence of colonization with intrinsics and the preponderance of pediatric patients with this condition, we used a matched-pairs design. Each intrinsic case was matched to a control using the following hierarchical criteria: (i) Diagnosis (malignant vs. non-malignant), (ii) disease risk (standard vs. high vs. non-malignant), (iii) donor type (matched sibling vs. matched unrelated donor vs. cord blood), (iv) conditioning intensity (myeloablative vs. reduced-intensity), and (v) age (± 10 years). The Prentice-Wilcoxon test was used to evaluate the matched pairs on the primary endpoints of overall survival (OS). For relapse and RFS, we excluded patients with non-malignant disorders.ResultsTable 1 shows the characteristics of the control group and intrinsics (n = 18 in each group). The groups were similar in all studied variables. The median follow up was 15 months. The intrinsic group showed a significantly higher 2-year OS of 86 [52-96]% vs. controls with OS of 35 [8-65]% at 2 years (P < 0.01, Figure 1). This remarkable difference in OS was due to a significantly lower NRM in the intrinsic group (0% vs. 36 [8-65]%, P= 0.01). Other transplant outcomes (GVHD and relapse) in each group were similar. Both deaths in the intrinsic group were due to relapse. In contrast, deaths in the control group were due to organ failure in 45%, relapse in 33%, infection in 11%, and GVHD in 11%.ConclusionsIn matched-pair analysis of intrinsically vancomycin-resistantenterococcivs. controls, we observed a remarkably lower NRM among patients colonized pre-HCT with E. gallinarum or E. casseliflavus .The mechanisms for this finding remain to be further explored. We hypothesize that in addition to vanC, these organisms have other genes that collectively contribute to establishment of a protective microbiome against various etiologies of early post-transplant NRM. This may occur as a result of beneficial microbial secondary metabolites that modulate the host immune system, or be consequent to colonization resistance against pathogenic organisms. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Clinical study of the biofilm of implant-supported complete dentures in healthy patients.

The purpose of this study was to quantify the area covered by biofilm and identify bacteria and yeasts present in mandibular acrylic resin full-arch implant-supported fixed prostheses. Biofilm control of implant-supported fixed prosthesis is hampered by their design, and it can cause oral and systemic problems, mainly in immunocompromised patients like the elder. Knowledge about microbiota reinforces the awareness about the need for periodic professional cleaning maintenance. Twenty prostheses were unscrewed, washed in 0.89% sodium chloride, stained with eosin 1% and photographed. The area covered by biofilm was digitally delimited and quantified. Biofilm samples were collected, diluted up to 1:107 , seeded in chromogenic agar media and incubated for 48hours, at 37°C, for counting of colony-forming units (CFU/mL). DNA hybridization was performed to complement the identification and quantification of microorganisms. Data were analyzed using Mann-Whitney test, Spearman correlation and Fisher's exact test (α=.05). An average of 62% of the gingival surface of the prostheses was covered by biofilm. Enterococcus spp. (5.82±1.38log10 CFU/mL) and Staphylococcus aureus (5.75±2.02log10 CFU/mL) showed higher prevalence in cultures. Patients with five implants had less biofilm compared to those with four implants (P=.031) but had higher Escherichia coli counts (P=.039). In DNA hybridization, Streptococcus pneumoniae, Veillonella parvula and Fusobacterium nucleatum presented higher quantification and were present in all the samples; patients over 65years old contained more Candida tropicalis (P=.049); prostheses on five implants presented lower quantification for several species. Biofilm was present on all prostheses, containing potentially pathogenic microorganisms. The number of implants may play a role in quantification of biofilm and in microorganism counts.

Detection of yeast species associated with respiratory tract infections using internal transcript spacer

Fungal infections have increased during last two years to become a grown threat due to the prevalence of COVID-19, which is the first factor to inhibit the immune system. Therefore, this study aimed to screen fungal species associated with respiratory infections using internal transcript spacer as diagnostic marker. The total samples collected in this study were 160 samples of sputum, which included filamentous fungi and yeasts. The total number of positive samples was 124 (77.5%) which included 62 yeast positive samples, and 62 filamentous positive samples. Yeast samples included different genera and the highest percentage belonged to the genus Candida. Five species of the genus Candida, C. tropical. C. albicans, C. dubliniensis, C. krusei and C. glabrata were identified based on phenotypic characteristics and biochemical tests as well as using chromogenic Candida agar medium. The highest percentage of isolated yeasts was Candida yeast 53, with a rate of )85.48%( out of 62 samples of yeasts.The highest percentage of yeasts was Candida albicanis, which amounted to 26 (41.93) positive samples for examination according to the genetic diagnosis of yeasts

Prevalence of Candida spp. Isolated from Urine Samples of Pregnant Women from Kassala State, Sudan

A urinary tract infection (UTI) is a major disease that affects people of all age groups. Women are more susceptible to UTI than men especially pregnancy, mainly due to the different structural features make easy contamination of the UTI with fecal flora. Candida is one of pathogenic which causing this problem. A total of 196 Clean-Catch midstream urine samples were collected from pregnancy referred to Kassala new Hospital and Abdurrahman Elmobark Medical center, their ages between 15 to 40 year old. Grams’ staining, chlamydospores formation and Chromogenic Agar medium used to differentiate between Candida spp. 17 (8.67%) were positive for Candida species, these were C. glabrata (41.18%), C. albicans (23.52%), C. krusei (17.66%), C. dubliniensis (11.76%) and C. tropicalis (5.88%). No co-existence of Candida species was found. In the present study C .glabrata and C. albicans scored the highest frequency of occurrence.

Rapid Detection of Candida species Isolated from Denture Stomatitis Patients using Phenotypic methods and Chromogenic agar media

Aims: The purpose of this study was Isolation and phenotypic identification of different candida species isolated from denture stomatitis patients. Materials and Methods : Over all 62 isolates of Candida species yielded from 43 patients attending prosthodontic departmentCollege of DentistryMosul universityDental teaching Hospital. Clinically, the samples processed by traditional methods including culture characteristics, gram staining reaction , germ tube, chlamydospore formation, culture on CHROM agar Candida , Sabouraud Dextrose agar, urea's test and Carbohydrates fermentation test. Results: All isolates were accurately diagnosed to the species level by various traditional methods , among the total of 62 Candida species , the predominant type was the Candida albicans which accounted for (46.8%) followed by Candida glabrata (33.9%), Candida tropicalis (17.7%), finally the species Candida krusei accounted for (1.6%). Conclusions: Candida albicans is highly spreading among patients wearing dentures particularly those suffering from denture stomatitis in which CHROM agar Candida medium is best method for rapid identification and documentation of different Candida species .

Molecular Identification and Hemolytic Activity of Candida Species Isolated from Urine of Healthy and Diabetic Women in Kurdistan of Iraq

A survey was carried out on the incidence of Candida yeasts in urine of healthy (non-diabetic) and diabetic women in Duhok and Zakho cities from February 2019 to April 2019. Out of 620 urine samples examined, 144 samples were found positive for Candida infection (23.2%). There were significant differences in incidence of Candida infection between urine of healthy and diabetic women as well as among age groups. All Candida isolates from positive samples were identified by using Chromogenic Candida Agar medium and confirmed by sequencing of the ITS1 and ITS4 region of rDNA. The identified Candida species were C.albicans, C.glabrata, C.krusei and C.tropicalis. The most common species was C.albicans (34%), followed by C.glabrata (29.9%), then C.tropicalis (13.8%), whereas, C.krusei (=Pichia kudriavzevii) displayed the least incidence (9.7%). All tested strains (n=83) for their hemolytic activity on Sabouraud's dextrose agar amended with sheep blood and glucose showed positive activity. Candida albicans and C.tropicalis displayed the highest hemolytic activity.

High prevalence of multidrug resistant uropathogens: A recent audit of antimicrobial susceptibility testing from a tertiary care hospital in Bangladesh.

Objectives:Urinary tract infections due to multi drug resistant bacteria have been on the rise globally with serious implications for public health. The objective of this study was to explore the prevalence of multi drug resistant uropathogens and to correlate the urinary tract infections with some demographic and clinical characteristics of patients admitted in a tertiary care hospital in Bangladesh.Methods:A cross sectional prospective study was conducted at Shaheed Ziaur Rahman Medical College Hospital, Bogura, Bangladesh among clinically suspected urinary tract infection patients from January to December, 2018. Clean-catch midstream or catheter-catch urine samples were subjected to bacteriological culture using chromogenic agar media. Antimicrobial susceptibility testing of the isolates was done by Kirby-Bauer disk diffusion method following Clinical and Laboratory Standards Institute guidelines. Descriptive statistical methods were used for data analysis.Results:Culture yielded a total of 537 (42.8%) significant bacterial growths including 420 (78.2%) multi drug resistant uropathogens from 1255 urine samples. Escherichia coli was the most common isolate (61.6%) followed by Klebsiella spp. (22.5%), Pseudomonas spp. (7.8%), Staphylococcus aureus (5.4%) and Enterobacter spp. (2.6%) with multi drug resistance frequency of 77.6%, 71.9%, 90.5%, 86.2% and 92.9% respectively. There was female preponderance (M:F; 1:1.97; P=0.007) but insignificant differences between paediatric and adult population (43.65% vs. 42.57%) and also among different age groups. Diabetes, chronic renal failure, fever and supra-pubic pain had significant association as co-morbidities and presentations of urinary tract infections (P<0.05). Multi drug resistance ranged from 3.7 to 88.1% including moderate to high resistance found against commonly used antibiotics like ciprofloxacin, cephalosporin, azithromycin, aztreonam, cotrimoxazole and nalidixic acid (28.6 to 92.9%). Isolates showed 2.4 to 32.2% resistance to nitrofurantoin, amikacin, netilmicin and carbapenems except Pseudomonas spp. (66.7% resistance to nitrofurantoin) and Enterobacter spp. (28.6 to 42.9% resistance to carbapenems).Conclusion:There is very high prevalence of multi drug resistant uropathogens among hospitalized patients and emergence of carbapenem resistance is an alarming situation. Antibiotic stewardship program is highly recommended for hospitals to combat antimicrobial resistance.

Fungal neonatal and infantile sepsis in Egypt: Risk factors and identification of fungal isolates

Background : Invasive fungal diseases (IFDs) are opportunistic infections associated with significant mortality in paediatric patients, especially in those with compromised immune system and neonates with very low birth weight (VLBW). The objectives of this study are to determine the prevalence, clinical features and fungi isolates of neonatal sepsis in three hospitals in Egypt. Methodology : The study is a cross sectional survey of 176 neonates with clinical sepsis admitted to the neonatal intensive care units (NICU) of the three hospitals over a period of one year (February 2015 to January 2016). A minimum of two blood samples (collected within 24 hours) from each neonate were cultured for bacteria in automated BacT/AlerT and conventional culture bottles, while Saboraud-Brain Heart Infusion broth was inoculated for fungi culture. Positive growths from the broth were sub-cultured on Sabouraud Dextrose Agar (SDA) plates for aerobic incubation at 25oC and 37oC for 2 weeks. Identification of fungi colonies on SDA was by conventional morphology and confirmation on chromogenic agar media. Phylogenetic analysis of representative fungi isolates was done by partial nucleotide sequencing of D1-D2 domain of the large subunit rRNA gene. Results : Of the 176 neonates, blood culture was positive for pathogens in 55 (31.3 %) samples and fungi were isolated in 26 (14.8 %); yeast (25) and mould (1). The commonly isolated yeasts were Candida albicans, Candida tropicalis , and Candida krusei representing 34.6%, 30.8% and 23.1%, respectively of the total fungi isolated. The phylogenetic analysis in comparison to Genbank data showed defined clades for Candida tropicalis, Candida parapsilosis, Candida albicans and Pichia kudriavzevii Conclusion : This current study highlights the changing pattern of neonatal infections in Egypt caused by Candida , with increasing incidence of infections caused by non-albicans Candida species. Key words : fungal infection, neonatal, risk factors, PCR, yeast

Pre-Engraftment Gut Colonization with Enterococcus Casseliflavus Improves Survival after Allogeneic Hematopoietic Cell Transplantation

Gut bacteria modulate the immune system and influence outcomes of allogeneic hematopoietic cell transplantation (HCT). We reported an unexpected association between pre-HCT gut colonization with intrinsically vancomycin-resistant enterococci (iVRE: E. gallinarum and E. casseliflavus) and better overall survival (OS). In an expanded cohort, now also including patients who were iVRE-colonized early post-HCT (before day +14), we demonstrate that the iVRE-OS association is specific to E. casseliflavus. We studied allo-HCT recipients who had ≥1 positive rectal swab or stool culture for iVRE (days -14 to +14). SpectraTM VRE chromogenic agar medium (ThermoFisher Scientific) was used for species-level identification. 66 (E. casseliflavus: 23, E. gallinarum: 43) of the 873 allograft recipients (2011-2017) met our inclusion criteria. As expected from the constitutive vancomycin resistance of iVRE, the groups did not differ in their prior exposure to different antibiotic classes. The groups were not different in patient, disease, or transplant characteristics, except a marginally higher frequency of sirolimus-based GVHD prophylaxis in the E. casseliflavus group (35% vs. 12%, P = 0.05). With a median follow up of 30 months, 3-year OS was better in patients with E. casseliflavus (91% vs. 62%, P = 0.04), due to lower 3-year non-relapse mortality (NRM: 0 vs. 18%, P = 0.05) (Fig. 1A-B). Only 2 patients with E. casseliflavus died within 3 years post-HCT, both due to relapse. In contrast, 14 patients with E. gallinarum died within 3 years: 7 (50%) due to relapse, and 7 (50%) from NRM (4 GVHD, 1 infection, 1 graft failure, 1 VOD). In multivariable analysis, E. casseliflavus gut colonization was associated with reduced all-cause mortality (HR 0.20, 95%CI 0.04-0.91, P = 0.04). There were no differences between the groups in 180-day acute grade II-IV GVHD (P = 0.19), 1-year chronic GVHD (P = 0.56), 100-day bacteremia (P = 0.59), or 100-day Clostridium difficile infection (P = 0.79). To probe the mechanism of this protection against mortality, first we mined 15 E. casseliflavus and 8 E. gallinarum genomes for 14 shikimate and tryptophan metabolism enzymes. This analysis predicted that E. casseliflavus encodes a larger number of enzymes in the tryptophan metabolism pathway (Fig. 1C). Several compounds in this pathway are ligands for the aryl hydrocarbon receptor (AhR). Signals downstream of AhR augment the gut barrier and modulate the immune system, potentially reducing injury and inducing protective responses. Next, we performed agar diffusion assays. We did not find significant bacteriocin production by E. casseliflavus, arguing against direct modulation of the gut microbiota (Fig. 2). Pre-engraftment gut colonization with E. casseliflavus, but not E. gallinarum, improves survival. Mechanistic studies of E. casseliflavus-host interactions can guide the development of novel microbiota therapeutics.

Pre-Engraftment Gut Colonization with Enterococcus Casseliflavus Improves Survival after Allogeneic Hematopoietic Cell Transplantation

▪Introduction: Gut bacteria modulate the immune system and influence outcomes of allogeneic hematopoietic cell transplantation (allo-HCT). The presence of Blautia, butyrate-producing Clostridia, and Eubacterium limosum in the stool has been associated with lower mortality after allo-HCT. We previously reported an unexpected association between pre-HCT gut colonization with intrinsically vancomycin-resistant enterococci (iVRE: E. gallinarum and E. casseliflavus) and improved overall survival (OS) due to decreased non-relapse mortality (NRM). In an expanded cohort, now also including patients who were iVRE-colonized early post-HCT (before day +14), we demonstrate that the iVRE association with improved OS is specific to E. casseliflavus.Patients and Methods: We studied allo-HCT recipients at our institution who had at least 1 positive rectal swab or stool culture for iVRE between days -14 and +14. New admissions for HCT were screened for gut VRE colonization weekly until discharge. SpectraTM VRE chromogenic agar medium (ThermoFisher Scientific) was used for species-level identification. Antimicrobial prophylaxis consisted of levofloxacin, acyclovir, and an azole. Cefepime was our empiric antibiotic for neutropenic fever.Results: 66 (23 with E. casseliflavus and 43 with E. gallinarum) of the 873 allograft recipients between 2011-2017 met our inclusion criteria. As expected from the constitutive, rather than acquired, vancomycin resistance of iVRE, the groups did not differ in their prior exposure to different classes of antibiotics. There were no significant differences between the groups in patient-, disease-, or transplant-related characteristics, except a higher frequency of sirolimus-based GVHD prophylaxis in the E. casseliflavus group (35% vs. 12%, P = 0.05). With a median follow up of 30 months, OS was significantly better in patients with E. casseliflavus (91% vs. 62% at 3 years, P = 0.04), due to lower NRM (0 vs. 18% at 3 years, P = 0.05) (Figures 1A and 1B). Only 2 patients with E. casseliflavus died within 3 years post-HCT, both due to relapse. In contrast, 14 patients with E. gallinarum died within 3 years post-HCT: 7 (50%) due to relapse, and 7 (50%) from NRM (4 GVHD, 1 infection, 1 graft failure, and 1 veno-occlusive disease). In multivariable analysis, E. casseliflavus gut colonization was significantly associated with reduced all-cause mortality (hazard ratio 0.20, 95% confidence interval 0.04-0.91, P = 0.04). There were no significant differences between the groups in 180-day acute grade II-IV GVHD (P = 0.19), 1-year chronic GVHD (P = 0.56), 100-day bacteremia (P = 0.59), or 100-day Clostridium difficile infection (P = 0.79). To probe the mechanism of this protection against mortality, we mined 15 E. casseliflavus and 8 E. gallinarum sequenced genomes for 14 shikimate and tryptophan metabolism enzymes. This analysis predicted that E. casseliflavus encodes a larger number of enzymes in the tryptophan metabolism pathway (Figure 1C). Several compounds in this pathway are ligands for the aryl hydrocarbon receptor (AhR). Signals downstream of AhR augment the gut barrier and modulate the immune system, potentially reducing pathogenic injury and inducing protective immune responses.Conclusions: Pre-engraftment gut colonization with E. casseliflavus, but not E. gallinarum, improves survival after allo-HCT. Future mechanistic studies of the interactions between E. casseliflavus and the host can guide the development of novel microbiota-oriented therapeutics in this high-risk patient population. DisclosuresWeisdorf:Seattle Genetics: Consultancy; FATE: Consultancy; SL Behring: Consultancy; Pharmacyclics: Consultancy; Equillium: Consultancy.

Chromogenic Agar Medium : A Versatile Tool for the Diagnosis of UTI

Objective: The present study was done on Chromogenic agar media to identify uropathogens more efficiently by its characteristic colony colour for each of the organism.Methodology: A total 300 sample were collected from Rajshahi Medical College Hospital, Bangladesh. Urine samples of the suspected UTI cases, showing pus cells &gt;5/HPF on microscopic examination were included for urine culture simultaneously onto Chromogenic agar media, Blood agar and MacConkey agar media.Results: Culture yielded 139 (46.33%) bacterial growth among them, 133 (44.33%) showed single organism and remaining 06 (2.00%) showed mixed growth of two organisms in different combinations. It is evident from the present study that both Chromogenic agar media and Blood agar (BA) media supported growth of all 145 bacteria, while MacConkey (MAC) agar yielded 133(91.72%) bacterial growths. The rate of presumptive identification of the isolates was found significantly higher (97.24%) on Chromogenic agar media when compared with the MacConkey agar (80.68%) and Blood agar (27.58%) media. Out of 91 E. coli isolated, 88(96.70%) could be identified differentially on Chromogenic agar media in contrast to 85(93.40%) on MacConkey agar and only 06(06.59%) on Blood agar. Again, all 06 (100%) of the isolate-pairs of mixed growth were identified distinctly on Chromogenic agar media, whereas both Blood agar and MacConkey agar media could revealed only 01(16.66%) of the polymicrobial growth.Conclusion: Chromogenic agar media has been documented for its very high yielding rate, rapid presumptive identification of both single and polymicrobial growths with greater precision and avoidance of biochemical tests for further identification of uropathogens. Thus it can be recommended as primary urine culture medium to be used by the clinical microbiology laboratories.TAJ 2012; 25: 64-71