In the post-implementation period, the GDH test was performed immediately upon stool sample arrival and then NAAT was performed. This two-step testing approach is supported by the 2019 guidelines from the American Society of Microbiology. In-vitro, glutamate dehydrogenase (GDH) catalyzes the reversible oxidative deamination of glutamate to α-ketoglutarate (α-KG). difficile were initiated versus 4/28 (14. If the second test shows you do not have toxins present, this means you do not have a C. 8%) were immunocompromised. The expression of GDH was determined by qPCR,. In summary, although the brain contains considerable amounts of GDH, under normal conditions, there is little evidence that the reaction is involved in the net synthesis of glutamate (Cooper, 2011a) (Fig. Since this sample was determined to be negative by TC, it was designated as a toxin A/B false-positive result. Pure isolates were characterized by PCR ribotyping. Rezultatele sunt exprimate calitativ: pozitiv/negativ 2. Intended Use: Premier C. dacă este pozitiv se confirmă ICD dacă este negativ este foarte probabilă colonizarea cu C. 25: COI <16. With Sofia 2 C. The device was then examined for the appearance of blue lines on the “Ag” and “Tox” sides of the reaction window. difficile toxin (high specificity but suboptimal sensitivity) to confirm the diagnosis of CDI. Tenover and colleagues reported that the GDH assay had lower sensitivity with specimens positive for ribotypes other than 027 . 2 cases per 10,000 patient bed-days. 1 vial containing mL of GDH C1 ontrol 6. The mariPOC GDH test reported five low-positive results for which true positivity could not be verified by other. 29150184. 3%) patients who were NAAT, GDH and toxin A&B EIA positive. No toxin EIA-positive case was found among GDH-negative samples, and 60. The systematic review and meta-analysis included eligible studies (those that had PICO [population, intervention, comparison, outcome] elements) that assessed the diagnostic accuracy of NAAT alone or following glutamate dehydrogenase (GDH) enzyme immunoassays (EIAs) or GDH EIAs plus C. diff toxin but positive for GDH, then a PCR test is conducted to detect the C. Fenner L, Widmer AF, Goy G, Rudin S, Frei R. difficile had significantly lower body mass index than those without. 4%), then C. Place all residents positive for C. A decision tree was constructed to compare two CDI diagnostic approaches (Microsoft Excel ® 2016) from the Japan government payer’s perspective: (1) one-step pathway with NAAT alone; (2) two-step algorithm with GDH/toxin followed by NAAT (stool samples were first tested with GDH and toxin; where GDH. We think that toxigenic culture with the alcohol shock method is a highly sensitive method for the detection of toxigenic C. Both tests are based on the ELFA (Enzyme-Linked Fluorescent. difficile in private rooms or co -hort whenever possible Post signage about the outbreak and proper hand hygiene using soap and water Restrict admissions if outbreak escalates or is prolonged Hold meetings, including housekeeping, to update staff on outbreak status. 3 4 Of note, a few. A recently marketed enzyme immunoassay for glutamate dehydrogenase (GDH), TechLab's C. This two-step testing approach is supported by the 2019 guidelines from the American Society of Microbiology. The algorithm previously in place in our facility was a two-step microliter plate ELISA, which required an initial screening ELISA for GDH, and all GDH-positive samples subsequently requiring a toxin ELISA for confirmation. Fecal microbiota transplant (FMT). If the result is GDH positive a second test is performed to look for toxins that are produced when C. Panel A, black bars, AL group; white bars, RF group; acute fasted and refed groups, not. The aforementioned reaction also yields ammonia, which in eukaryotes is canonically processed as a substrate in the urea cycle. Georgia COVID-19 status of cases and hospitalizations with interactive charts and graphs. The patient is an asymptomatic carrier of toxigenic C. The GDH test had a negative predictive value of 98. Of these, TL-GDH was positive with all and TR-GDH was positive with 50 samples. Because results of antigen testing alone are nonspecific, antigen assays. Samples with equivocal or negative CDAB results should be referred for further testing, such as molecular detection of toxin genes, toxigenic culture (TC) or cell. If the CDAB results are positive, laboratory diagnosis of CDI can be made. In summary, the C. Detection of C. According to our validation studies, discordant results occur in about 6% of cases. 2017. 63 ng/mL for toxin A, 0. Antigen detection for C. taking a 10-day course of another antibiotic that can treat the C. diff is causing an infection. Because results of antigen testing alone are nonspecific, antigen assays have been employed in combination with tests for toxin detection, PCR, or toxigenic culture in two-step testing algorithms. The mean CDI incidence in 2012 was 5. test for GDH will generally rule out the infection. Un rezultat negativ nu exclude prezenta unei afectiuni asociate cu Clostridium difficile. Confirmatory tests (TC or PCR) are needed in 60% of GDH-positive/toxin EIA-negative cases. 142), respectively. The GDH test has high sensitivity and. Once we assume the pretest probability was in the range 15–25%, PPV was 65–78% and NPV was 97–98%. 2%; one sample yielded one toxigenic and one nontoxigenic strain, another had two distinct toxigenic strains isolated), while 10 (2. difficile antigen, glutamate dehydrogenase (GDH), in stool specimens to screen patients suspected of having a C. GDH is found in all organisms, but in animals is allosterically regulated by a wide array of metabolites. What does GDH positive-toxin negative mean? As described above, the first test of the sample will look for the chemical GDH, if the. However, a more specific test to detect free toxins is required to confirm the diagnosis for glutamate dehydrogenase (GDH)-positive and toxin-negative samples. Toxigenic culture was performed for 41 samples with discrepant results, and 39 were. If the GDH is negative, CDI can effectively be ruled out due to a greater than 95% sensitivity of the GDH assay. 5 μmol, Lyophilized) 1 vial 4. Fenner and colleagues have also applied this three-step approach. materii fecale (coprorecoltor. Detecting GDH for the diagnosis of CDI had both high sensitivity and. 2%) specimens were GDH positive/toxin negative; toxigenic strains were isolated from 21 (4. 5% of discordant cases with known GDH/toxin testing results were GDH positive/toxin negative. Glutamate dehydrogenase (GDH) is a hexameric enzyme that catalyzes the reversible conversion of glutamate to α-ketoglutarate and ammonia while reducing NAD(P) + to NAD(P)H (Figure 1) []. The most likely explanation for this discrepancy is cross-reactivity to toxins formed by other clostridial species, such as C. The staining intensity of GDH-positive samples ranged from light yellow to tan to sepia and was mainly located in the. difficile culture-negative specimens. GDH from animals, but not other kingdoms [ 2 ], is allosterically regulated. Read more. Am făcut analiza din scaun și a ieșit pozitiv atât pt toxina A cat și pt toxina B. Using this algorithm, they found a sensitivity of 84% and specificity of 99. Only in the animal kingdom is this enzyme heavily allosterically regulated by a wide array of metabolites. difficite GDH Positive Control. difficile Solution. difficile. ) (Quik Chek). The patient has nontoxigenic C. Of 38 samples, 27 revealed a positive result for GDH and free toxins A/B in the stool, and 11 samples only for the presence of GDH. Therefore, the currently used multi-step algorithm is a reasonable solution. difficile is currently performed as a two-step process. Rapid, accurate detection of Clostridioides difficile toxin may potentially be predicted by toxin B PCR cycle threshold (tcdB Ct). diff Quik Chek Complete; Alere Inc. A toxin assay is. A large conformational difference between open and closed GDH system. These EIA tests were initially not very sensitive and therefore were often used as an initial screening tool, paired with other tests to confirm positive results. ram. The School Aged Surveillance, Age Trends, LTCF Weekly, and LTCF Percent Positivity Reports have been discontinued. If the GDH test is negative the stool sample is reported as negative for CDI If the GDH test is positive the lab proceeds to the second stage of testing which is toxin detection. PCR positive, toxin negative patients have low levels of C. Identification of Clostridium difficile–associated diarrhoea Clinical features. If the PCR test is positive, then the result is reported as positive for C. The detection of toxin indicates the presence of actively. Testul detecteaza prezenta antigenului Chlamydia Trachomatis in secretia cervicala sau uretrala. Compared with NAAT, the GDH test had a sensitivity of 87. An ELISA for C. Meta-analysis of published evidence supports the use of testing algorithms that use NAAT alone or in combination with GDH or GDH plus toxin EIA to detect the presence of C. Cultivarea este metoda cu sensibilitate cea mai ridicată și este importantă pentr u evaluari epidemiologice. difficile infection in those at high risk of repeat episodes. VIDAS toxins A/B positive, and 44. However, the clinical significance remains unclear in cases that demonstrate a positive. Esistono in commercio test in grado di riscontrare entrambe le tossine e altri capaci di rilevare solo la tossina A. Bovine GDH (Sigma Aldrich) and the complemented strain’s cytosol were used as a positive control. Abstract Clostridium difficile (C. 3% with a κ value of 0. Stop Solution 1, Premier C. She has had 6 surgeries in her lifetime. The patient is an asymptomatic carrier of toxigenic C. Glutamate dehydrogenase (GDH) antigen is an enzyme that is produced by C. Un rezultat pozitiv pentru bacteriile C. Surprisingly, only 30% of our small healthy control group were anti-GDH positive. In this study, two chemiluminescent immunoassays (CLIAs), one for GDH and the other for the toxins A. In this study, the performance of the Clarity assay was compared to that of a multistep algorithm using an enzyme immunoassay (EIA) for detection of glutamate dehydrogenase (GDH). (1987) suggested that GDH distribution in rat brain is similar to that of the known glutamatergic pathways and, as such, astrocytic GDH expression may be relevant to areas where high levels of tonic synaptic activity is expected. The detection of GDH does not distinguish between toxigenic and nontoxigenic strains. 2 Clostridium difficile gdh pozitiv? Din Comunitate. 7) and 0. The Xpert C. TEXT. Real-time PCR targeting the C difficile toxin B gene if toxin and GDH results are discordant. Of 60 CDPCR-negative patients, only two (3%) were removed from single room isolation. difficile, de aceea testul nu poate face diferenţierea între tulpinile toxigene şi tulpinile. difficile bacteria. diffidile GDH is a rapid qualitative enzyme immunoassay screening test. D. As expected, the GDH EIA turns. Specimens with discordant results (ie, GDH-positive but toxin-negative or GDH-negative but toxin-positive) proceed to the second step: reflex (at additional charge and additional CPT code) to a PCR C difficile gene detection test. 0%) were GDH positive. difficile sau antigenul C. The very poor specificity, however, limits the interpretation of a positive result, and specimens positive for the GDH antigen require subsequent testing with a different test (6). Buna seara, Am fost diagnosticata cu clostridium difficile (toxina A pozitiva) si am luat tratament Metronidazol timp de 10 zile. The GDH activity contained by different mammalian tissues is known to vary widely [62,88,89]. In the two-round workflow for the diagnosis of CDI by applying GDH and CD toxin A/B testing, when GDH and CD toxin A/B were both negative or both positive, the use of VIDA, RIDA, and QCC for first-round testing in a two-round workflow eliminated the requirement for second-round testing in 71. In the present single-centre prospective study we focused on these ‘difficult-to-interpret’ samples and characterized them by anaerobic culture,. Positive results usually correlate well with clinically significant CDI but negative results do not rule out C. The staining intensity of GDH-positive samples ranged from light yellow to tan to sepia and was mainly located in the. Figure 4. 5-100%, and NPV, reported to be 94. The initial screening test will be a combination glutamate dehydrogenase (GDH) and C. A total of 141 specimens from 141 patients yielded 27 TPs and 19% prevalence. ️ 독소 생성에 상관없이 검출되므로 비특이적인 시험. In others, nontoxigenic strains represented less than 10 percent of GDH-positive fecal specimens. difficile infection event, which requires either a positive NAAT or toxin-based assay. 11 of the 246 samples (4. A subgroup of these samples could neutralize both toxins from RT027. 2–96. difficile toxin can be detected (C. 160 discrepant results (148 GDH+ and 12 toxins+) were tested by PCR, 117 were positive (107/148. difficile PCR assay (Cepheid, Sunnyvale, CA) was performed according to the manufacturer's instructions. Of these, 10 (52. As an important antigen, glutamate dehydrogenase (GDH) has been proposed as a preliminary screening test target for CDI. e False negative GDH assay. The premier GDH involved undertaking an enzyme immunoassay looking for the presence of GDH as previously. 7%. 3. A screen of genes encoding B-GUS and GDH was performed for fecal microbiome data from healthy individuals ( n = 103) and from CRC patients ( n = 53), which revealed a decrease in abundance of taxa with confirmed GDH and HCA transformation activity in CRC. C. We prefer to use the GDH-only assay (C. Twelve samples (3. positive, low positive, and high negative samples were prepared from negative stool spiked with C. The most likely explanation for this discrepancy is cross-reactivity to toxins formed by other clostridial species, such as C. difficile by Cepheid)From the swab samples obtained in Laguna, direct detection of the S. difficile 균이 증식하고, 동시에 독소를 분비하여 발생하는 항생제 관련 설사병 (antibiotic-associated diarrhea, AAD. An alternate 2-step algorithm is initial GDH testing, followed by toxin A + B enzyme immunoassay or NAAT if GDH is positive. The patient has nontoxigenic C. difficile with higher confidence (three-step algorithms). It used to be called Clostridium difficile. A test of cure is not recommended. difficile. vancomycin) szükséges. C difficile cytotoxicity neutralization assay. A positive result for both the GDH and toxin indicates C. positive for Toxin A and negative for GDH, further analysis 7. Across test arms (i. DISCUSSION: Using GDH antigen as the screening and toxin A and B as confirmatory test for C difficile, 85% of specimens were reported negative or positive within 4 h. 2% GDH-positive but toxin A/B-negative specimens need to be retested by another assay, such as PCR, which has higher sensitivity, longer test turnaround time, and higher costs. In this study, GDH was also positive in two of the four culture-negative stool samples. It is an anaerobic, spore-forming, Gram-positive rod. Diff Quik Chek Complete D-EIA provides a rapid and reproducible first-line screening assay for laboratory diagnosis of C. We investigated the performance of a two-step algorithm for diagnosis of CDI using detection of glutamate dehydrogenase (GDH). GDH? (Glutamate Dehydrogenase) Patient Information Leaflet If you require a translation or alternative format of this leaflet please call Infection Prevention & Control 01296 315337 The fact that you are GDH positive will be recorded on your electronic patient record. GDH-positive patients were considered infected or colonized, and those who were faecal toxin-positive were considered to be infected (i. This variation in test performance in regard to ribotype supports the varied reports seen in the literature regarding GDH sensitivity . 08. GDH este un antigen comun tuturor tulpinilor de C. 4%) were positive by GDH and negative by the other three methods, consistent with non-toxin producing C. Interestingly, immunostaining results showed that metastatic lymph nodes and liver metastases lesions had higher levels of GDH expression (Figure 2 E and F). We calculated sensitivity, specificity, positive and negative predictive values as measures of test performance, as well as local prevalence. difficile bacteria. A betegség sokszor az antibiotikumok túlhasználatának eredménye, mert a bélben meghonosodott, az emberi szervezetre ártalmatlan. Store the test cards at 2-8 C when not in use. 클로스트리디오이데스 디피실 장염(Clostridioides difficile Infection, CDI)이란 항생제를 투여받는 환자의 장관에 정상 세균총 (colonic flora) 구성이 변화하면서 C. 7%) were toxin-positive and 126 (84. difficile are commercially available. They should be. GDH positive specimens are tested by cytotoxin/ CDAB VIDAS assay for confirmation of toxin production. Xpert C. In this study, we evaluated these three immunoassays for. Direct PCR was done for GDH, toxin A and B genes (gluD, tcdA and tcdB). Súlyosabb fertőzöttség esetén 10-14 napos speciális antibiotikumkúra (pl. In recent years, the diagnostic method of choice for Clostridium difficile infection (CDI) is a rapid enzyme immunoassay in which glutamate dehydrogenase (GDH) antigen and C. T positive for Toxin B and negative for GDH, further analysis GDH and Toxin A are negative. A true positive (TP) was defined as positivity by CCNA or positivity by LAMP plus another test (GDH, CDT, or the Premier C. Și nu știu care sunt riscurile pt făt atât cauzate de bacterie cat și de tratament. In contrast to previous reports, GDH-positive specimens were retested by a rapid toxin A/B test instead of time-consuming and labor-intensive CCNA (). difficile-positive stool samples identified at our institution during a 12-month period, to compare. Glutamate dehydrogenase (GDH) is a key enzyme that catalyzes the final reaction of the glutamine metabolic pathway, and has been reported implicated in tumor growth and metastasis. difficile)-associated diarrhea (CDAD) is a challenging nosocomial infectious disease. Samples that are NAAT- or GDH-positive but toxin-negative may represent C. We classified PTP as follows: Not done: clinician did not document clinical decision making regarding CDI. Your stool (poo) has been tested and has shown you carry the GDH chemical in your gut. Reflex testing is performed at an additional charge. 5%) were ALERE GDH-toxinsShe has had 5 episodes of c diff, one Fecal transplant and now on the 6th episode of GDH positive but negative toxins. difficile in either one or both of the 2 algorithms. This positive control is in a liquid bovine serum albumin based matrix with non- azide preservative. Specimens with uncertain (GDH-positive and toxin-negative) results were tested in parallel using Xpert and GenomEra for confirmation. difficile toxins (conditioned media) produced by RT027 (26%). Follow-up toxin testing with specimens that are GDH-positive or NAAT-positive provides the most accurate information to the physician tasked with diagnosing CDI. Of these, 2278 were confirmed as GDH positive/toxin negative and 440 were assumed to be GDH positive/toxin negative. Introduction. În cazul unui rezultat pozitiv al analizei C. Samples with GDH-negative and toxin-positive results are rarely observed and need to be retested. difficile in the sample, but presence of toxin is unknown. difficile infection. Thus, toxin EIA is utilized to rule in CDI, but NAAT is used to rule out CDI with this multi-step algorithm. Methods: We performed a retrospective cohort study evaluating all C. To our best knowledge, this is the first study investigating the prevalence and course of anti-GDH antibodies. The infection can sometimes be treated at home, or you might need to go into hospital. Six (7%) samples only were GDH positive and toxin positive by the Liaison® test alone. SIR, which adjusts for denominator and change in testing methodology. The prevalent direction of the GDH reaction is determined by cell- and tissue-specific metabolic networks. difficile Toxins A+B card, both from Biotical Health. Toxin B is positive. However, current assays based on GDH activity or GDH. 1%) had a GDH-positive, toxin-negative EIA result. → 독소생성유무를 추가로 확인해야 하는 단점 One GDH-negative but toxin A/B-positive sample was identified by both QCC and RC. GDH positive, toxin negative: C. ” Parasitological examinations and rotavirus and adenovirus antigen detection tests were. Of 200 GDH-negative samples, 3 were positive by PCR only. When positive by itself and compared to clinical diagnosis of C. Detection of a GDH-positive EIA-toxin-positive result in a subsequent stool. In Young Yoo, M. diffidile GDH Positive Control, ImmunoCord C. The performance of the two-step protocol was compared with toxin detection by the Meridian Premier EIA kit in. A Clostridium difficile fertőzés kezelése az alábbiak szerint történhet: Az aktuálisan szedett antibiotikum abbahagyása, amennyiben az lehetséges. There was no false positive result for CDT according to our criteria. Introduction. difficile assay by the Leeds laboratory as part of an internal evaluation. 3%) were positive for both GDH and toxins, and 23 (13. dif ficile DNA and for preliminary. difficile - GDH, se efectuează gratuit analiza C. iv. GDH is a homohexameric enzyme that is regulated by various allosteric effectors, e. The GDH-EIA-CCCN procedure required, on average, 2 days to complete testing on GDH-positive results, while testing by the Xpert C. g. i. Only 25% of the isolates were GDH positive with NAD+ as. Clostridium difficile - GDH - metode și materiale folosite. diff gene. Difficile Tox A/B II enzyme immunOassay (Tox-A/B) was compared with an in-house cytotoxin assay and no test was able to detect toxin in all samples with true-positive. difficile toxin antigen assay. difficile infekció Eredménykiadás Eredménykiadás vagy 3. At least 36% of 53 CDPCR-positive results did not influence bed management. One in-house PCR and artus PCR false-negative sample remained negative upon retesting by both PCRs, while both in-house and artus PCR on the cultured strain were positive. A positive GDH test alone does not meet the NHSN definition of a C. 1%). 1) [ 1 ]. Follow-up positive screening results with a test to confirm and to detect the presence of toxins: Toxins, by enzyme immunoassay (EIA) tests; these tests are rapid but less sensitive. Patients. However, neuronal GDH activity is two to five times lower than it is in astrocytes, where it must compete with highly expressed glutamine synthase that. This study included all GDH-positive and four GDH-negative samples from August 1st to October 22th 2013 (defined as the first period), and all samples submitted from May 20th to June 5th 2014 (defined as the second period), without knowledge of the patients' clinical information. Background: A multistep algorithm using GDH antigen plus toxin with a reflex PCR is an acceptable method for detecting CDI. If the result is GDH positive, a second test is performed to look for toxins that are produced when C. . A/B. 4% and 97. No. Results: A total of 2,138 specimens were initially tested. The performance of the GDH test was assessed against the following reported gold standard test methods: C, CTA and TC, although most studies carried out only one of these. Method. diff. Stage one of these tests looks for a chemical called glutamate dehydrogenase (GDH). Clinical correlation is required, with consideration of repeat C. †Positive GDH result, combined with negative toxin (CDAB) result may be arbitrated by molecular testing (NAAT). diff is causing an infection. difficile infection (CDI) in many studies with high sensitivity and negative predictive values. diff). difficile culture and/or PCR. This approach provides confirmatory results for >90% of specimens submitted for testing. We identified 483 patients with positive CD PCR targets. 9–99. , and Swindells et al. GDH is a very rapid, inexpensive and easy method. C. The cross-reactivity of GDH detection with other cultured Clostridia was reported for one sample in a previous study by Alfa et al. GDH Positive 50 14 Equivocal 0 0 98. În unele laboratoare, un test GDH pozitiv asociat cu un test imunoenzimatic (EIA) negativ pentru toxină va fi lucrat pentru confirmare printr-un test de amplificare a acidului nucleic (NAAT), de obicei, PCR. Assuming the patients who were GDH positive and toxin equivocal/negative as possible CDI, the incidence was 0. We have added new references and. Results: There were 59 discordant and 44 positive cases HO CDI cases from October 2017 through September 2019: (1) There was no difference in age and sex between the. culture-positive specimens. difficile disease. , NAAT only, GDH/NAAT, or GDH/toxin/NAAT), the pretest probabilities (or prevalences) of the presence of C. 1016/j. Seventy-nine were positive by the GDH antigen assay only. 2% and the positive predictive value. sordellii , which produce. Clostridioides difficile is an anaerobic, spore-forming Gram-positive bacillus and one of the most commonly reported pathogens in health care-associated infections []. difficile culture/PCR was 93. The clinical spectrum of C. 16 ng/mL for toxin B, 0. If both are positive, the test is reported as positive for CDI. Preventing the spread of the bacteria to others It is important to wash your hands thoroughly with soap and water after using the toilet or commode and before eating. dacă este pozitiv se confirmă ICD • dacă este negativ este foarte proba bil colonizare cu C. GDH este un antigen comun tuturor tulpinilor de C. Ce inseamna acest lucru? Hospital databases were used to collect information on glutamate dehydrogenase (GDH)-positive, toxin-negative inpatients (February–April 2015). While the GDH assay negative result is generally trustful, a positive GDH assay leads to wrong diagnosis for a third or a fourth of the tested population. diff gene. DIFF Quik Chek Complete® test (Alere) for the detection of GDH. However, it’s clinical significance and role in colorectal cancer (CRC) pathogenesis is largely unknown. healthcare-associated (i. As an alternative multi-step process, SHEA/IDSA list performing a NAAT toxin gene test followed by a toxin test (rather than a NAAT test by itself). difficile testing yielded the highest sensitivity and NPV, in the least amount of time, of the individual- and multiple-test algorithms evaluated. T Toxin A and Toxin B are positive. In 7/31 (22. Clostridium difficile gdh pozitiv? Din Comunitate. Nine (10%) samples were GDH positive and toxin negative by both tests, but were positive by PCR. Article. GDH catalyzes the reversible oxidative deamination of glutamate to α-ketoglutarate and plays a central role in nitrogen glutamate metabolism, cellular energy homeostasis, and. difficile toxin A, Toxin B, Toxin A&B, glutamate dehydrogenase (GDH) 등을 검사할 수 있다. GDH POSITIVE Patient Information Leaflet Infection Prevention Team . 2%) were positive in the GDH test, leading to a sensitivity and NPV of 89. difficile-specific antibodies indicating prior C. If GDH positive and toxin negative, then do PCR. Chemiluminiscență / Enzyme Linked Fluorescent Assay (ELFA) Material uzual. Open in a separate window. difficile causes disease via toxin production, leading to intestinal mucosal damage. 3%) patients who were NAAT, GDH and toxin A&B EIA positive. suis-specific gdh gene yielded 87. Xpert C. difficile GDH card and biotical C. difficile infection. 3%) were positive for GDH with 34 samples (97. There were 40 male patients and 27 female patients. If this is found in your sample, this means that you have C. difficile culture-negative result (6, 9). Clearly then, GDH was a reasonable screening test with an enhanced ability to detect positives compared to both solid phase EIA and ICD for detection of toxin A/B in feces. diff testing checks a sample of your stool (poop) for signs of an infection with a bacteria called C. Samples with a result negative for GDH but positive for one or both toxins (GDH–/ToxA+/ToxB– or GDH–/ToxA–/ToxB+) need to be retested, as this is an invalid result. , a molecular assay). To date,15 genes have been found to be associated with the pathogenesis of CHI. 139 were positive for GDH and toxins.