Enzyme-linked Fluorescent Immunoassay Research Articles

Differential expression of long noncoding RNA in hepatocellular carcinoma on top of chronic HCV and HBV infections.

Aim of the studyThe task of long noncoding RNAs (lncRNAs) as a prospective goal for hepatocellular carcinoma (HCC) is a candidate for research. Several lncRNAs are involved in signal transduction, directing gene expression and epigenetic alteration in normal and cancer cells. Dysregulation of diverse lncRNAs has been involved in the pathogenesis and progression of different cancers including HCC. We aimed to investigate the differential expression of lncRNAs (aHIF, hPVT1, ANRIL) in HCC on top of chronic hepatitis C virus (HCV) and hepatitis B virus (HBV) infections.Material and methods182 participants were included: 85 patients with HCC in addition to 50 patients with cirrhosis on top of chronic HCV or HBV, and 47 healthy subjects as controls. HCC was diagnosed by triphasic computed tomography (CT). Detection of α-fetoprotein (AFP) and serological markers of HCVAb and HBsAg by enzyme-linked fluorescent immunoassay (ELFA) and quantitation of lncRNAs by real time PCR were applied.ResultsUpregulation of ANRIL and hPVT1 and downregulation of aHIF were observed in patients with HCC on top of HCV and HBV vs. controls. Circulating aHIF could be of major diagnostic importance to discriminate HCC on top of HCV from cirrhotic patients with sensitivity 86.67% and specificity 91.89% whereas circulating hPVT1 had sensitivity 85.0% and specificity 84.62%; moreover ANRIL had AUC 0.902 and could discriminate HCC on top of HBV from cirrhotic patients.ConclusionsThe differential expression of lncRNAs (ANRIL, hPVT1 and aHIF) might be of major worth in predicting the occurrence of HCC in cirrhotic patients related to chronic viral hepatitis and could be beneficial in the early management.

1198. Measurement of Pre-transplant Anti-cytomegalovirus (CMV) Immunoglobulin G Titer to Predict Risk of CMV Infection in CMV-seropositive Kidney Transplant Recipients

BackgroundAlthough cytomegalovirus (CMV)-seropositive solid organ transplant recipients have a lower risk of CMV infection compared with CMV-seronegative recipients, some patients remain at risk of CMV infection after transplant. Low pre-transplant anti-CMV immunoglobulin G (IgG) titer has been reported as a predictor of CMV infection in CMV-seropositive liver and heart transplant recipients, but this association in CMV-seropositive kidney transplant (KT) recipients has not been explored. We investigated the pre-transplant anti-CMV IgG titer and other CMV infection risk factors in CMV-seropositive KT recipients.MethodsThis retrospective study was conducted on CMV-seropositive KT recipients aged >18 years old at Ramathibodi Hospital during 2017 and 2018. The cumulative incidence of CMV infection was estimated with Kaplan–Meier methodology. The pre-transplant anti-CMV IgG titer was measured with an enzyme-linked fluorescent immunoassay. Risk factors for CMV infection were analyzed with Cox proportional hazards models.ResultsOf the 340 included CMV-seropositive KT recipients (37% female; age [mean±SD]: 43±11 years), 69% and 64% received deceased-donor allograft and induction therapy, respectively. The anti-CMV IgG titer was < 20 and >20 AU/ml in 7.1% and 92.9% of patients, respectively. During a mean follow-up of 14 months, the cumulative incidence of CMV infection was 14.8%, including both asymptomatic CMV infection (69%) and tissue-invasive disease (31%). A pre-transplant anti-CMV IgG titer of < 20 AU/ml was significantly associated with CMV infection in both the univariate analysis (HR, 2.70; 95%CI, 1.21–6.05, [p=0.02]) and the multivariate analysis (HR, 2.98; 95% CI, 1.31–6.77, [p=0.009]). Other significant risk factors of CMV infection included older donor age (HR, 1.03; 95% CI, 1.01–1.06, [p=0.005]), anti-thymocyte induction therapy (HR, 2.90; 95% CI 1.09–7.74, [p=0.033]), and prolonged cold ischemic time (HR, 1.06; 95% CI, 1.02–1.10, [p=0.002]).ConclusionA low pre-transplant CMV-specific humoral immunity is independently associated with post-transplant CMV infection in CMV-seropositive KT recipients. The universally available anti-CMV IgG titer test could potentially stratify those at risk and target preventive strategy appropriately.Disclosures All Authors: No reported disclosures

Development of a modified enrichment method for the rapid immunoassay of Escherichia coli O157 strains in fresh cut vegetables

Escherichia coli O157:H7 is a pathogen that colonizes human intestinal epithelial membrane and causes a characteristic lesion and severe syndromes, including diarrhea, hemorrhagic colitis, hemolytic uremic syndrome, and thrombotic thrombocytopenic purpura. It is difficult to isolate and identify this pathogen. The purpose of this research was to establish a two-stage enrichment method for the detection of E. coli O157:H7 in fresh cut vegetables. Fresh cut vegetable samples were first enriched in modified EC broth with novo-biocin at 42°C for 6 hr, and then transferred to sorbitol MacConkey broth containing cefixime and tellurite at 35°C for 18 hr. Finally, the enriched broth was verified for the existence of E. coli O157 by using an automated enzyme-linked fluorescence immunoassay (mini-VIDAS) or an immunostrip test. This two-stage enrichment method would decrease the false-positive E. coli O157 tested by immunostrip or mini-VIDAS. The pathogen in food sample could be as low as 10 CFU/g and selectively enriched to 105 or 107 CFU/mL required for the detection by mini-VIDAS or immunostrip. The presence of E. coli O157:H7 in enriched broth was confirmed by multiplex polymerase chain reaction (PCR). Thus, the two-stage enrichment method can be used to rapidly screen food samples for E. coli O157.

Investigation on contamination status of Staphylococcus aureus from food and processing in Chengdu

To understand the contamination status of Staphylococcus aureus in food and processing. From July 2017 to January 2018, raw/cooked meat products, aquatic products, soybean products and other foods for sale were collected from five districts and counties of Chengdu, and some processing samples were collected from school cantons, farms and slaughterhouses of Chengdu. Staphylococcus aureus in food and processing in Chengdu was detected by plate method and PCR method, staphylococcus aureus enterotoxin was determined by enzyme-linked fluorescence immunoassay, and Risk Ranger software was used for semi-quantitative Risk assessment. A total of 429 samples were collected from food and processing in Chengdu. 78 strains(18. 2%) of Staphylococcus aureus were detected by plate method, among which 76 strains were identified as Staphylococcus aureus by PCR. The highest detection rate was found in raw meat(34. 1%), and the highest detection rate was found in raw chicken(54. 2%). The detection rate of Staphylococcus aureus in samples from farmers&apos; markets(34. 0%) was higher than that of supermarkets(28. 3%). Eighteen of the 78 strains produced enterotoxin, raw chicken and duck meat from supermarkets(9) and farmers&apos; markets(6), and hand smears by school cafeteria workers(2). According to the risk score, the food safety risks are in descending order from raw meat products(55 points), soybean products(50 points), cooked meat products(43 points) and aquatic products(43 points). Raw meat and soybean products are high risk foods contaminated by S. aureus, cooked meat and aquatic products are medium risk foods.

Hubungan antara Kadar Feritin dengan Malondialdehyde pada Pasien Talasemia β Mayor di RSD dr. Soebandi Jember

Repeated blood transfusions, increased iron absorption, and ineffective erythropoiesis in major β thalassemia patients lead to iron overload characterized by elevated ferritin levels. Free iron will catalyze reactive oxygen species (ROS) formation by Fenton reaction that cause oxidative stress. Malondialdehyde (MDA) is the lipid peroxidation end product used to measure the oxidative stress. This study aimed to determine the correlation between ferritin levels and MDA levels in major β thalassemia patients at dr. Soebandi Hospital Jember. An analitic observational study with cross sectional study design which the subjects were 15 patients with major β thalassemia in the Pediatric Department at dr. Soebandi Hospital Jember who met inclusion and exclusion criteria. Ferritin levels measured by Enzyme-Linked Fluorescent Immuno Assay (ELFA) method and MDA levels measured by Thiobarbituric Acid Reactive Substances (TBARS) method using spectrophotometer at 535 nm. Data was analyzed with Shapiro Wilk normality test and Pearson correlation test. The mean of ferritin levels was 3540,46±3925,37 ng/mL and MDA levels was 4,77±2,03 nmol/mL. The result showed that there is strong positive correlation between ferritin levels and MDA levels with p value=0,001 and r=0,786 in major β thalassemia patients at dr. Soebandi Hospital Jember.

Phosphodiesterase 8B Polymorphism rs4704397 Is Associated with Infertility in Subclinical Hypothyroid Females: A Case-Control Study.

BackgroundSubclinical hypothyroidism (SCH) remains largely unnoticed as a major cause of infertility due to asymptomatic. Polymorphisms of phosphodiesterase 8B gene (PDE8B) have been linked with various diseases, including female infertility. Hence, we aimed to study prevalence of SCH, in infertile females, explore associa- tion of PDE8B rs4704397 A/G and rs6885099 G/A polymorphisms with infertility in females suffering from SCH and genotype-phenotype correlation of the polymorphisms with thyroid stimulating hormone (TSH) levels in Gujarat population.Materials and MethodsIn this retrospective study, TSH level was estimated from plasma of 230 infertile and 100 control females by enzyme-linked fluorescence immunoassay (ELFA) to find out the prevalence of SCH. Further, based on TSH levels, thyroid function test (TFT) was performed in controls and infertile females with subclinical hypothyroidism (IF-SCH). PDE8B rs4704397 and rs6885099 polymorphisms were genotyped by PCR-RFLP and ARMS-PCR, respectively in 74 controls and 60 IF-SCH females.ResultsWe observed i. significantly high prevalence of SCH (32%) in the infertile females, ii. significant- ly lower frequency of ‘G’ allele (P=0.006), while the frequency of ‘A’ allele (P<0.0001) was higher in IF- SCH females, compared to the controls, for rs4704397 A/G SNP, iii. no significant difference in the genotype (P=0.214; OR=2.51; CI=0.74–8.42) and the allele frequency (P=0.129; OR=1.51; CI=0.92-2.47) of rs6885099 G/A SNP, iv) low linkage disequilibrium for the polymorphisms, v. significantly higher frequency of ‘AA’ hap- lotype (P=0.0001; OR=3.84; CI=1.86-8.01),while the ‘GG’ haplotype (P=0.0023; OR=0.33; CI=0.16-0.69) was significantly lower in IF-SCH females and vi. no significant difference in the TSH level of IF-SCH females with respect to the genotypes.ConclusionThe present study reports an association of PDE8B rs4704397 polymorphism with infertility in SCH females. The study categorically shows a higher prevalence of SCH in infertile females of Gujarat and advocates the importance of screening for SCH in infertility management.

Seroprevalence and potential risk factors associated with Toxoplasma gondii infection in women from Tripoli, Libya

Aims: To determine the seroprevalence of Toxoplasma gondii (T. gondii) in women from Aljalla Maternity and Gynaecology Hospital (AMGH) and to evaluate the association between the infection and potential risk factors. Methods: A cross-sectional study was conducted at Aljalla Maternity and Gynaecology Hospital (AMGH) in Tripoli during the year 2012. Data on potential risk factors were collected by a structured questionnaire and results of the test. The output data of the questionnaire were used to assess potential risk factors for a positive outcome. All sera (n= 500) was screened against ToxoG, by using the Vidas machine automated enzyme-linked fluorescent immunoassay (ELFA). Association between the outcome variables and its potential risk factors were screened in a multivariate analysis. A p-value

The Role of Nuclear Factor Kappa B Rs28362491 Single Nucleotide Gene Polymorphism in Recurrent Embryo Implantation Failure

Background: Embryo implantation is a very intricate process, which is controlled by a number of complex molecules like hormones, cytokines, growth factors and their cross talk at feto-maternal interface. The transcription factor nuclear factor kappa B (NF-κB) induces the expression of various pro-inflammatory genes, including those encoding cytokines and chemokines, and also participates in inflammasome regulation. Aim of the present study:was to investigate the possible associations between NF-κB rs28362491 single nucleotide gene polymorphism and susceptibility to repeated implantation failure (RIF). Subjects and Methods: This study was conducted on 120 subjects subdivided into 2 groups: 60 women with successful implantation asacontrol group (Group I), and 60 womendiagnosed withRIF(Group II). They were subjected to full history taking, clinical examination and investigated for molecular testing of the NF-κB -94 ins/del ATTG (rs28362491) polymorphism by lymphocyte separation and extraction of DNA for polymerase chain reaction (PCR) together with determination of serum concentration of day 3 follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol II (E2), prolactin and thyroid stimulating hormone (TSH) concentrations by an automated quantitative enzyme-linked fluorescent immunoassay (ELFA). Results: A significant difference in the genotype distribution of the NF-κB rs28362491 between those with RIF and controls. Specifically, subjects with RIF had a significantly higher frequency of the NF-κB rs28362491 del allele than that of controls. Conclusion: This study showed a significant association between rs28362491 in the promoter region of the NF-κB gene and RIF. NF-κB appears to be a triggering factor of orchestrated gene regulation during embryo implantation.

Laboratory testing for factor VIII and IX inhibitors in haemophilia: A review.

Inhibitors are antibodies directed against haemophilia treatment products which interfere with their function. Factor VIII (FVIII) inhibitors in haemophilia A and factor IX (FIX) inhibitors in haemophilia B are significant clinically when they require a change in a patient's treatment regimen. Their persistence may increase morbidity and mortality. Multiple laboratory tests are now available for detecting and understanding inhibitors in haemophilia. Inhibitors are traditionally measured by their interference in clotting or chromogenic factor assays. They may also be detected using immunologic assays, such as enzyme-linked immunosorbent assay or fluorescence immunoassay. Anti-FVIII or anti-FIX antibodies of IgG4 subclass best correlate with the presence of functional inhibitors. Improvements in inhibitor measurement have been recently introduced. Preanalytical heat treatment of patient specimens allows testing of patients without delaying treatment. Use of chromogenic and immunologic assays may aid in identification of false-positive results, which are frequent among low-titre inhibitors. Validated reagent substitutions can be used to reduce assay cost. New methods for defining assay positivity and reporting low-titre inhibitors have been suggested. Challenges remain in the areas of quality control, assay standardization, monitoring of patients undergoing immune tolerance induction therapy and testing in the presence of modified and novel treatment products.

The Correlation between Ferritin Levels and Glutation (GSH) Levels in Major Beta Thalassemia Patient at dr. Soebandi Jember Hospital

Repeated blood transfusions in patient with Major Beta Thalassemia leads to iron overload marks by the increased of serum ferritin levels. Free iron caused the change of H2O2 to oxidants by fenton reaction and caused oxidative stress. These oxidants will be counteracted by GSH as antioxidants. The purpose of this study was to investigate the correlation between ferritin levels with GSH in patients with major beta thalassemia in RSD dr. Soebandi hospital Jember. The samples of this study are fifteen (15) patients age 1-18 years who were regularly transfused. Serum ferritin levels were measured by Enzyme-Linked Fluorescent Immuno Assay (ELFA) and plasma GSH levels were measured by Ellman method. Data was analyzed using Pearson correlation test. Serum feritin levels were increased in Major Beta Thalassemia children with average of 3540,46 ± 3925,37 ng/mL. The mean of GSH is 10,46 ± 2,58 µmol. We found significant and negative correlation between serum ferritin and GSH with p value=0,000 and r=-0,951 in Major beta thalassemia patient at RSD dr. Soebandi Jember.&#x0D; Keywords: Thalassemia, Oxidative stress, Feritin, GSH

Association between C-reactive protein and interleukin-6 levels in subclinical hypothyroid patients

Background: The relationship between subclinical hypothyroidism (SCH) and cardiovascular disease has been one of the most popular topics recently. Our study aims to investigate the presence of the well-known preceding clinical situations of atherosclerosis such as endothelial dysfunction and inflammation in SCH. Materials and Methods: The study population comprised 50 patients with recently diagnosed SCH and 50 healthy controls. Thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were estimated by enzyme-linked fluorescent immunoassay for the diagnosis of SCH. Total cholesterol (TC), triglycerides, and high-density lipoprotein cholesterol (HDLC) were estimated by kit method in Siemens machine. Low-density lipoprotein cholesterol (LDLC) and very LDLC were calculated using Friedewald formula. Inflammatory marker C-reactive protein was estimated by kit method in Siemens and IL-6 by enzyme-linked immunosorbent assay. Results: In this study, the level of TSH ± standard deviation (8.56 ± 1.26 vs. 0.63 ± 0.16) was significantly higher ( Conclusion: This study suggests that SCH patients have increased inflammatory markers along with dyslipidemia due to that the future risk of further development of cardiovascular disorder can occur. Level of inflammatory makers increases in patients as disease progresses if left untreated.

Augmented oxidative stress in infertile women with persistent chlamydial infection

There is established association between oxidative stress, infections of genital tract and fertility. Genital tract infections may provoke increased production of free radicals and generate oxidative stress that can be involved in pathophysiology of a number of reproductive diseases and complications during pregnancy. The aim of this study was to determine connection between oxidative stress and infertility associated with persistent chlamydial infection. Serum samples of infertile women with tubal factor infertility (TFI), women with multiple spontaneous abortions (MSA) and fertile women was screened for C. trachomatis MOMP specific IgG and IgA antibodies and cHSP60 specific igG antibodies using ELISA. The levels of superoxide anion radical, nitric oxide and reduced glutathione were determined spectrophotometricaly. Serum levels of testosterone, luteinizing hormone and follicle stimulating hormone were determined by enzyme-linked fluorescent immunoassay method. Our results showed that persistent infection was more prevalent in TFI than in MSA group, whereas seropositivity was higher in MSA than in TFI group of patients. We also found that superoxide anion was significantly lower, while LH was markedly higher in TFI and MSA group of patients. However, when our results were analyzed according to the serological status of chlamydial infection, we found that parameters of oxidative stress, superoxide anion and index of oxidative stress, defined as relative ratio between superoxide anion and nitrites sum and glutathione ((O2−+NO2−)/GSH) were significantly elevated in infertile patients with persistent chlamydial infection compared to seropositive and seronegative patients. Our findings point to the possible impact of Chlamydia trachomatis infection on prooxidative-antioxidative balance that can influence fertility potential in women with persistent chlamydial infection.

PERBANDINGAN PENENTUAN KADAR TIROKSIN ENZYME LINKED IMMUNOFLUORESCENT ASSAY (ELFA) DAN ENZYME LINKED IMMUNOSORBANT ASSAY (ELISA)

The determination of thyroxin (T4) is known as a good indicator to know the condition of thyroid function. In the hyperthyroid state, are shown clearly the increased levels of T4, while in the hypothyroid state their levels always decrease. The T4 levels change due to the physiological and pathological conditions on the ability of thyroxin binding globulin (TBG). The T4 measurement can be performed using an enzyme-linked fluorescent immunoassay (ELFA) or enzyme-linked immunosorbant assay (ELISA). Both ELFA and ELISA can detect T4 antigen. In these research fifty one randomized samples sera from the Clinical Pathology laboratory, at Dr. Soetomo Hospital, consisting of 11 males and 40 females, were studied. They were comparing using ELFA and ELISA to know the levels of T4. In this study the method used is a cross sectional observational, and the statistical analysis with nonparametric Spearman Correlation Rank's test and Wilcoxon Signed Rank's Test. In the results by using ELFA were found the mean and SD values 8.78 μg/dL/5.39 μg/dL, whereas by ELISA 11.06 μg/dL/5.38 μg/dL. These results showed a correlation between ELFA and ELISA with rs 0.576. The T4 levels results showed as follows, hypothyroid ELFA 8 (15.7%), ELISA 6 (11.8%); normal levels ELFA 32 (62.7%), ELISA 29 (56.9%); hyperthyroid ELFA 11 (21.6%), ELISA 16 (31.4%) with p 0.090 which was not considered significant. It can be concluded from the showen results that in the determination of T4 concentration using ELFA gave a lower yield compared with ELISA. Further examination is required by special treatment of the sample or other way to find out which one is the best way for determination of T4 levels.

Evaluation of the VIDAS glutamate dehydrogenase assay for the detection of Clostridium difficile

We evaluated the performance of the VIDAS GDH assay for the detection of Clostridium difficile. In total, 350 fecal specimens collected from patients clinically suspected of having CDI were analyzed by C. difficile culture and enzyme-linked fluorescent immunoassay (VIDAS GDH); the results were compared with those of toxigenic C. difficile culture (TC), PCR (Xpert C. difficile assay), and toxin AB EIA (VIDAS CDAB). The numbers of culture-positive and culture-negative samples were 108 and 242, respectively. The concordance between the GDH assay and C. difficile culture was 90.3%. With PCR, 12 more samples were found to be positive in GDH-positive/C. difficile culture-negative specimens. Thus, the concordance between GDH assay and C. difficile culture/PCR was 93.7%. The sensitivity, specificity, positive predictive value, and negative predictive value of the VIDAS GDH assay were 97.2%, 87.2%, 77.2%, and 98.6%, respectively, based on the C. difficile culture, and 97.5%, 91.7%, 86.0%, and 98.6%, respectively, based on C. difficile culture/PCR. Positivity rates of the GDH assay were partially associated with those of semi-quantitative C. difficile cultures, which were maximized in grade 3 (>100 colony-forming unit [CFU]) compared with grade 1 (<10 CFU).We evaluated the two-step or three-step algorithm using GDH assay as a first step. No toxin EIA-positive case was found among GDH-negative samples, and 60.8% (48/79) were TC- and/or PCR-positive among the GDH-positive/toxin EIA-negative samples. Thus, approximately 25% of the 350 samples required a confirmatory test (TC or PCR) in the GDH-toxin EIA algorithm, whereas only 2.3% of the total samples in GDH-PCR algorithm was discrepant and required another confirmatory test like TC.

Metal Stable Isotope Tagging: Renaissance of Radioimmunoassay for Multiplex and Absolute Quantification of Biomolecules.

The unambiguous quantification of biomolecules is of great significance in fundamental biological research as well as practical clinical diagnosis. Due to the lack of a detectable moiety, the direct and highly sensitive quantification of biomolecules is often a "mission impossible". Consequently, tagging strategies to introduce detectable moieties for labeling target biomolecules were invented, which had a long and significant impact on studies of biomolecules in the past decades. For instance, immunoassays have been developed with radioisotope tagging by Yalow and Berson in the late 1950s. The later languishment of this technology can be almost exclusively ascribed to the use of radioactive isotopes, which led to the development of nonradioactive tagging strategy-based assays such as enzyme-linked immunosorbent assay, fluorescent immunoassay, and chemiluminescent and electrochemiluminescent immunoassay. Despite great success, these strategies suffered from drawbacks such as limited spectral window capacity for multiplex detection and inability to provide absolute quantification of biomolecules. After recalling the sequences of tagging strategies, an apparent question is why not use stable isotopes from the start? A reasonable explanation is the lack of reliable means for accurate and precise quantification of stable isotopes at that time. The situation has changed greatly at present, since several atomic mass spectrometric measures for metal stable isotopes have been developed. Among the newly developed techniques, inductively coupled plasma mass spectrometry is an ideal technique to determine metal stable isotope-tagged biomolecules, for its high sensitivity, wide dynamic linear range, and more importantly multiplex and absolute quantification ability. Since the first published report by our group, metal stable isotope tagging has become a revolutionary technique and gained great success in biomolecule quantification. An exciting research highlight in this area is the development and application of the mass cytometer, which fully exploited the multiplexing potential of metal stable isotope tagging. It realized the simultaneous detection of dozens of parameters in single cells, accurate immunophenotyping in cell populations, through modeling of intracellular signaling network and undoubted discrimination of function and connection of cell subsets. Metal stable isotope tagging has great potential applications in hematopoiesis, immunology, stem cells, cancer, and drug screening related research and opened a post-fluorescence era of cytometry. Herein, we review the development of biomolecule quantification using metal stable isotope tagging. Particularly, the power of multiplex and absolute quantification is demonstrated. We address the advantages, applicable situations, and limitations of metal stable isotope tagging strategies and propose suggestions for future developments. The transfer of enzymatic or fluorescent tagging to metal stable isotope tagging may occur in many aspects of biological and clinical practices in the near future, just as the revolution from radioactive isotope tagging to fluorescent tagging happened in the past.

Increase of Clostridium difficile in Community; Another Worrisome Burden for Public Health

Background: Increasing rates of Clostridium difficile infection (CDI) have been reported mainly in Europe and North America; however, only limited reports have originated in Korea. The current epidemiology of CDI in the community could help to understand the outpatient healthcare environment and to extend infection control measures to outpatient settings. Methods: C. difficile isolates in NHIS Ilsan Hospital from 2012 to 2014 were included in this study. Clinical characteristics, acquisition types, and previous antimicrobial therapy were obtained via Electronic Medical Records. C. difficile culture was performed only in unformed stool. Toxin was positive by enzyme-linked fluorescent immunoassay (ELFA) in 247 specimens. In addition, toxin B and binary toxin gene were detected by PCR in 57 specimens. CDI was defined by toxigenic C. difficile isolation in unformed stool. Results: In the previous 3 years, 251 unduplicated C. difficile cases have been detected; 168 healthcare facility-associated hospital onset (HCFA-HO), 45 healthcare facility-associated community onset (HCFA-CO), and 38 community-associated (CA). Toxin positive rates by ELFA for toxin AB19:7-12)

High Seroprevalence of Toxoplasma Gondii Infection in Female Sex Workers: A Case-Control Study.

Through an age- and sex-matched case-control study, we sought to determine whether female sex workers have an increased risk of Toxoplasma gondii exposure and to determine the sociodemographic, work, clinical, and behavioral characteristics of these workers associated with T. gondii exposure. Female workers (n = 136) and controls (n = 272) were examined with enzyme-linked immunoassays (EIA) for the presence of anti-Toxoplasma IgG and IgM antibodies. IgM positive sera were additionally tested with enzyme linked-fluorescence immunoassay (ELFA). Anti-T. gondii IgG antibodies were found in 21 (15.44%) of 136 cases and in 10 (3.67%) of 272 controls (OR = 4.05; 95% CI: 1.84–8.89; P = 0.0001). Anti-T. gondii IgG levels higher than 150 IU/ml were found in 13 (9.6%) of 136 cases and in 8 (2.9%) of 272 controls (P = 0.007). Anti-T. gondii IgM antibodies were found in two cases and in six controls by EIA, but all were negative by ELFA. T. gondii seropositivity was associated with being born out of Durango State (OR = 10.47; 95% CI: 2.9–36.8; P < 0.01), injuries during sex work (OR = 6.30; 95% CI: 1.1–33.7; P = 0.03), and soil contact (OR = 4.11; 95% CI: 1.2–14.0; P = 0.02). This is the first report of an association of T. gondii infection and female sex workers.

Risk factors for cytomegalovirus reactivation after liver transplantation: can pre-transplant cytomegalovirus antibody titers predict outcome?

Despite preexisting cytomegalovirus (CMV) immunity, CMV-seropositive liver transplantation (LT) patients remain at risk of CMV infection. We hypothesized that the pre-transplant CMV antibody titer correlates with the risk of CMV reactivation. We conducted a retrospective study of CMV-seropositive LT recipients who did not receive anti-CMV prophylaxis from 2007 to 2013. The pre-transplant CMV immunoglobulin G (IgG) titer, which was measured with an enzyme-linked fluorescent immunoassay, was assessed as a risk factor for CMV reactivation with multivariate Cox proportional hazards models. The population consisted of 225 CMV-seropositive LT patients with a median age of 57 years (interquartile range, 47-62 years). The CMV titer distributions were as follows: <60 (40%) and ≥60 AU/mL (60%). The Kaplan-Meier estimates for CMV infection were 17% at 3 months, 18% at 6 months, and 19% at 12 months after transplantation. In a univariate analysis, a marginally significant increased risk of CMV infection was seen in LT recipients with a pre-transplant CMV IgG titer<60 AU/mL versus ≥60 AU/mL [hazard ratio (HR), 1.79; 95% confidence interval (CI), 0.98-3.28 (P=0.06)]. This risk was statistically significant in the subgroup of recipients who received allografts from CMV-seropositive donors [HR, 2.21; 95% CI, 1.15-4.26 (P=0.02)]. In a multivariate analysis, a pre-transplant CMV IgG titer<60 AU/mL was significantly associated with CMV infection [HR, 3.11; 95% CI, 1.60-6.03 (P<0.001)]. The other risk factors were high body mass index, donor CMV seropositivity, prolonged cold ischemic time, use of an interleukin-2 receptor antagonist for induction therapy, and high numbers of post-transplant infections. A lower pre-transplant CMV antibody titer is significantly associated with CMV infection after LT. Quantitative measurement of CMV-specific humoral immunity may have a potential role in improving the CMV prevention strategy in CMV-seropositive LT recipients.

Evaluation of the illumigene C. difficile assay for toxigenic Clostridium difficile detection: a prospective study of 302 consecutive clinical fecal samples

Toxigenic Clostridium difficile is a major pathogen causing nosocomial diarrhea. Consequently, rapid detection of toxigenic C. difficile is very important in clinical laboratories. The illumigene C. difficile DNA amplification assay (illumigene; Meridian Bioscience, Inc.) is a rapid method that detects the toxin A gene (tcdA) by loop-mediated isothermal amplification. In the present study, we evaluated the diagnostic performance of the illumigene assay using 302 consecutive stool specimens in comparison with the VIDAS C. difficile A&B enzyme-linked fluorescent immunoassay (VIDAS-CDAB; bioMérieux). Toxigenic culture was used as the reference method. The sensitivity, specificity, positive predictive value, and negative predictive value of the illumigene assay were 88.1%, 96.7%, 86.7%, and 97.1%, respectively, while those of the VIDAS-CDAB assay were 40.4%, 98.8%, 87.5%, and 88.5%, respectively. It is of note that use of a combination of the illumigene and VIDAS-CDAB assays did not improve any of the 4 evaluated parameters (88.1%, 95.5%, 82.5%, and 97.1%, respectively). The illumigene assay showed limits of detection of 250 and 11,467 CFU/mL for ATCC 9688 (tcdA+, tcdB+, cdtB−) and ATCC 43598 (tcdA−, tcdB+, cdtB−) reference strains, respectively, and there was no cross-reactivity with 8 frequently isolated bacterial species. In conclusion, the illumigene assay might be a useful method for rapid detection of toxigenic C. difficile in clinical laboratories. Additionally, the VIDAS-CDAB assay seems unnecessary if the illumigene assay is used.

G98(P) Susceptibility to Varicella Zoster in children with cystic fibrosis

IntroductionVaricella zoster virus (VZV) infection can result in significant morbidity in patients with cystic fibrosis (CF), and the risk of severe pulmonary complications rises with age. This is a greater...