The Luminex Gastrointestinal Pathogen Panel (xTAG(®) GPP) detects in one assay the most common gastroenteritis-causing pathogens and toxins, namely adenovirus 40/41, norovirus genogroup (NG) I/II, rotavirus A, Clostridium difficile toxin A/B, Campylobacter sp., Escherichia coli O157, Enterotoxigenic E. coli heat-labile enterotoxin/heat-stable enterotoxin, Salmonella sp., Shiga-toxin producing E. coli, Shiga-like toxin (Stx)1/2, Shigella sp., Vibrio cholerae, Yersinia enterocolitica, Cryptosporidium sp., Entamoeba histolytica and Giardia sp. In this study, we compared the results that were obtained by testing 393 faecal samples, collected during November and December 2011 at our laboratory, using the xTAG(®) GPP assay with the results of the routine diagnostic procedure. This procedure includes culture for bacteria and real-time PCR for viruses and parasites, but only if the test was requested by the clinician. If the clinician did not request the test for an xTAG(®) GPP-positive target, real-time PCR assays were used to confirm xTAG(®) GPP positivity. Discrepant results were also tested with real-time PCR assays. A total of 83 targets were detected in 76 samples using xTAG(®) GPP. The xTAG(®) GPP assay detected 43 additional positives compared with the routine diagnostic procedure, of which 11 targets could not be confirmed by real-time PCR. The non-confirmed targets were Campylobacter (one sample), Salmonella (four samples), Shigella (one sample) and E. histolytica (five samples). The xTAG(®) GPP was shown to be a convenient and sensitive assay for detection of 15 major gastrointestinal pathogens in a single molecular test, but for detection of E. histolytica and Salmonella, a confirmatory assay is indicated.

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Genotyping of cytomegalovirus (CMV) is useful to examine potential differences in the pathogenicity of strains and to demonstrate coinfection with multiple strains involved in CMV disease in adults and congenitally infected newborns. Studies on genotyping of CMV in dried blood spots (DBS) are rare and have been hampered by the small amount of dried blood available. In this study, two multiplex real-time PCR assays for rapid gB and gH genotyping of CMV in DBS were developed. Validation of the assays with 39 CMV-positive plasma samples of transplant recipients and 21 urine specimens of congenitally infected newborns was successful in genotyping 100% of the samples, with gB1 and gB3 being the most prevalent genotypes. Multiple gB and gH genotypes were detected in 36% and 33% of the plasma samples, respectively. One urine sample from a newborn with symptomatic congenital CMV was positive for gB1 and gB2. DBS of congenitally infected newborns (n ‫؍‬ 41) were tested using 9 l of dried blood, and genotypes were detected in 81% (gB) and 73% (gH) of the samples, with gB3 being the most prevalent genotype. No clear association of specific genotypes with clinical outcome was observed. In conclusion, the CMV gB and gH PCR assays were found to be rapid, sensitive for detecting mixed infections, and suitable for direct usage on DBS. These assays are efficient tools for genotyping of CMV in DBS of congenitally infected newborns. C ytomegalovirus (CMV) is the most common cause of congenital infection worldwide and an important viral pathogen affecting immunocompromised patients (13, 21). Both in congenitally infected newborns and in immunocompromised patients, genotyping of CMV has been used to study potential differences in pathogenicity of specific strains. However, few authors describe a correlation between specific CMV genotypes and severity of disease (29,32,34,40). More important, genotyping of CMV has enabled the discrimination of reactivation of latent virus from reinfection with new CMV strains in transplant patients, allowing a better definition of donor-to-recipient transmission patterns (24). Congenital CMV infections mainly result from recurrent infections among pregnant women (37), comprising both reactivation and reinfection. The discrimination of reactivation from reinfection may give insight into the mother-to-fetus transmission pattern and the possible associations with the outcome of congenital CMV infections.Genotyping of CMV has mainly focused on envelope glycoproteins gB (UL55) and gH (UL75), which play a role in virus entry and are major targets for neutralizing antibody response. The most frequently used methods for genotyping of CMV are nucleotide sequence analysis (27) and restriction fragment length polymorphism of PCR products (25, 28). Recently, real-time PCR-based assays have been used for rapid detection and quantification of CMV gB and gH genotypes (12,15,24,26). However, they have mainly been applied to plasma or other high-volume samples. Also, deep-sequencing-based methods, sensitive in the de...

Congenital cytomegalovirus (CMV) infection is the most common congenital viral infection worldwide. The sequela encountered most frequently is hearing impairment, affecting approximately one out of five infants congenitally infected. Data on the birth prevalence and risk factors of congenital CMV infection in the Netherlands are scarce. The aim of this study was to determine the birth prevalence of congenital CMV in the Netherlands. A sample of 6,500 dried blood spots (DBS) from infants born in the Netherlands was tested anonymously for CMV DNA. The sample was stratified by the number of live births in different regions of the Netherlands of the year 2007. Additionally, on a regional level, risk factors for congenital CMV were analyzed. The birth prevalence of congenital CMV in the Netherlands was 0.54% (35/6,433, 95%CI 0.36-0.72). Congenital CMV infection was significantly higher in regions with more than 15% young children (0-5 years) compared with regions with a lower proportion of young children (OR 5.9, 95%CI 1.4-25.2). Congenital CMV infection was significantly higher in regions with more than 30% immigrants compared with regions with a lower proportion of immigrants (OR 2.2, 95%CI 1.1-4.6). This association was strongest for regions with more than 30% non-Western immigrants (OR 3.3, 95%CI 1.5-7.5). Based on the knowledge of the natural history of congenital CMV infection, approximately 1,000 children are born with congenital CMV infection in the Netherlands annually, of whom eventually approximately 180 children (0.1% of all newborns) will be affected by long term sequelae, with hearing loss being the symptom encountered most frequently.

DRA is an accurate, rapid and easy to perform phenotypical susceptibility test for HSV-1.