29150184. potential C. Am un copil de 3 ani și jumătatea care a fost diagnosticat cu GDH pozitiv. sordellii , which produce. lamblia genetic assemblages. diff is causing an infection. Chemiluminiscență / Enzyme Linked Fluorescent Assay (ELFA) Material uzual. Of the nine “GDH-positive and toxin A/B-negative” specimens, six exhibited positive results by toxigenic culture. 1. A total of 400 samples were submitted during the first period. difficile. the presence of toxigenic C. Organs with high enzyme levels include the liver, brain, kidney, pancreas, adrenals and placenta [1,62,66,89,90,91]. Of the 47 episodes in which the stool was found to be culture positive with a toxigenic strain, 32 related to inpatients, and, on checking the prescribing records, we found that C. proteins. 4% and 97. Ce inseamna acest lucru? For GDH positive specimens, CDAB testing should be performed subsequently to detect toxin production. At the recent American Society for Microbiology (ASM) Microbe 2017 meeting, the interest in molecular testing versus algorithm testing was apparent from overflow attendance at several symposia, including “The C. If. A positive GDH test alone does not meet the NHSN definition of a C. According to our validation studies, discordant results occur in about 6% of cases. The two specimens that were negative with the mariPOC GDH test but positive with TechLab GDH and bacterial identification culture were negative with GenomEra PCR and with both toxin tests (samples 1 and 2). GDH is found in all organisms, but in animals is allosterically regulated by a wide array of metabolites. There were 40 male patients and 27 female patients. TEXT. When using a membrane assay, which combines GDH and Toxin A/B tests (see Figure 2: Testing Algorithm 2), samples with either both positive, both negative, or GDH positive toxin negative results can be reported as above. C. For the microbiological diagnosis of a Clostridium (C. Test: Enzyme-linked immunosorbent assay (ELISA) for the glutamate dehydrogenase (GDH) antigen What it tests for: The presence of C difficile organisms Commonly known as the antigen test, this test uses antibodies to test for presence of the GDH enzyme, a protein preserved in all C difficile bacteria. difficile GDH card and biotical C. The recombinant protein His 6-TF-TrGDH was affinity purified with nickel-nitrilotriacetic acid. 16 ng/mL for toxin B, 0. An ELISA for C. Intended Use: Premier C. Patients who tested positive by C. • Positive results determine the presence of Clostridium difficile antigen GDH in stool samples; nevertheless, it can be due to A positive result should be followed up with additional laboratoryThe remaining 10% being GDH positive should be tested for toxin A/B gene on the same day and positive results left to a final decision by the physician. Diff Quik Chek Complete assay is very simple to perform and permitted the very rapid reporting of final results for up to 88% of. Metoda. DIFF Quik Chek Complete® test (Alere) for the detection of GDH. difficile strains, A + B + was the dominant type, followed by A − B + strains. Sunt disperata deoarece înțeleg ca tratamentul nu este ok în sarcina trimestrul 1. The current assay also has a very high positive predictive value (99%) when both the GDH and toxin are positive. Un rezultat pozitiv pentru bacteriile C. difficile infection. diff. Briefly centrifuge all small vials prior to opening. 0) 78. Toxin assay will be performed. Of the remaining low number of specimens that are positive by GDH or NAAT. Refer to vial for exact concentration. 1. e. Therefore, enrichment cultures or additional real-time PCR tests are recommended for GDH-positive, culture-negative samples. A toxin assay is. NCBI. Antigen detection for C. Background: In the medical laboratory, a step-by-step workflow for Clostridioides difficile infection (CDI) detection using glutamate dehydrogenase (GDH) and toxin A/B assays for initial screening, along with a nucleic acid amplification test (NAAT), has been recommended recently. Since both toxigenic and nontoxigenic C. difficile infection. Though none of the assays could detect. We subsequently reviewed patient records to describe CD PTP at the time GIPCR was ordered. Focar De Infecţie Cu Clostridium Difficile Într-Un Spital Județean Din România, Decembrie 2013-FEBRUARIE 2014Sixty of the 96 GDH-positive CCNA-negative samples were tested with the Xpert C. 4%) were positive by GDH and negative by the other three methods, consistent with non-toxin producing C. Living + Magazine Issue 1 - Positive Living BCThe patient has nontoxigenic C. To our best knowledge, this is the first study investigating the prevalence and course of anti-GDH antibodies. toxin. GDH (glutamate dehydrogenase) is an enzyme present in C. Store the test cards at 2-8 C when not in use. Abstract Clostridium difficile (C. The clinical characteristics 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. diff infection, but you carry the C. Furthermore, this finding implies that, among cases that are initially GDH positive and toxin negative by fecal testing, many toxin-positive CDI cases may be missed . The patient has nontoxigenic C. Both forms have bound cofactor NADH and the inhibitor. If the CDAB results are positive, laboratory diagnosis of CDI can be made. 7% of the stool samples, respectively. diff. Positive GDH assay results must. 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. difficile detected or 2) false positive GDH. Genotypic characterization of 45 Xpert PCR-positive stools was performed by sequencing of the tcdC gene and PCR ribotyping. 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. diff infection is treated by: stopping any antibiotics you're taking, if possible. We classified PTP as follows: Not done: clinician did not document clinical decision making regarding CDI. duodenalis was detected in three. In this study, two chemiluminescent immunoassays (CLIAs), one for GDH and the other for the toxins A. 3%) patients who were NAAT, GDH and toxin A&B EIA positive. The positive and negative likelihood ratios were 10. Article. difficile contact. Following the algorithm, culture was. A Clostridium difficile-fertőzés kezelése. GDH catalyzes the reversible oxidative deamination of glutamate to α-ketoglutarate and plays a central role in nitrogen glutamate metabolism, cellular energy homeostasis, and. 1. ram. difficile colonization (the GDH test was positive, but the toxin test was a true negative). difficile common antigen) and toxin EIA but follow up with NAAT as an arbitrator of GDH-positive, toxin-negative stools. A two-step diagnostic algorithm is recommended to detect Clostridium difficile infections; however, samples are regularly found that are glutamate dehydrogenase (GDH) positive but stool toxin negative. difficile. The sensitivities and specificities of GDH-CYT and GDH-Xpert PCR were 57% and 97% and 100% and 97%, respectively. †Positive GDH result, combined with negative toxin (CDAB) result may be arbitrated by molecular testing (NAAT). Culture failure was observed in 11 (13%) samples, of which seven were positive by PCR. 63 ng/mL for toxin A, 0. 4 % vs 6. 8%) were immunocompromised. If the GDH is positive, the next step is to perform an. GDH is considered a screening method because it is expressed by both the toxigenic and nontoxigenic strains. dif ficile DNA and for preliminary. If the EIA toxin A/B is negative, the final result is determined with a PCR. Method. difficile Toxins A+B card, both from Biotical Health. 6%) dogs were positive for A/B toxins using the enzyme immunoassay kit and 18 (15. Introduction. PCR-RFLP analysis was carried out by digesting the secondary PCR products of the nested-PCR of bg and gdh genes. difficile” and “direct cytotoxicity positive. GDH negative Report as: C difficile antigen not detected GDH positive C difficile antigen detected. We observed that GDH was highly expressed in 56 of the 104 (53. PCR Test (-) No toxigenic CDI present with positive GDH test due to one of 2 possibilities: 1) Non-toxigenic C. 8%) were immunocompromised. When test findings were compared to the gold standard, GDH was not detected in 4 samples that were positive for TC, and the toxigenic strains were not isolated in four (4) GDH+/TOXIN+ samples. Newer rapid tests for CDI may reduce this. 4. As an important antigen, glutamate dehydrogenase (GDH) has been proposed as a preliminary screening test target for CDI. Where there is a negative GDH but a positive toxin test the sample should be retested, as this is an invalid result. Symptom duration was significantly shorter in patients with toxin-negative rather than toxin-positive stool specimens, despite the lack of CDAD drug treatment in all but one of the 29 toxin. difficile; however, some culture-negative stool samples can be detected by molecular examination. However, the low efficiency of the catalysis hinders the use of GDH in industrial applications. difficile PCR testing, and the results would be available within an additional 1 h. 139 were positive for GDH and toxins. Analytical sensitivity: 0. Dupa ce am terminat tratamentul, am refacut analiza si a iesit negativ pt toxinele A si B, in schimb e pozitiv clostridium difficile GDH. difficile disease. e. The cross-reactivity of GDH detection with other cultured Clostridia was reported for one sample in a previous study by Alfa et al. The aforementioned reaction also yields ammonia, which in eukaryotes is canonically processed as a substrate in the urea cycle. 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. In 7/31 (22. iv. Direct PCR was done for GDH, toxin A and B genes (gluD, tcdA and tcdB). This method comprises inoculating a stool filtrate onto a cell culture and observing a specific cytopathic effect (cell rounding) after 1 or 2. The most likely explanation for this discrepancy is cross-reactivity to toxins formed by other clostridial species, such as C. Therefore, enrichment cultures or additional real-time PCR tests are recommended for GDH-positive, culture-negative samples. fost negativ (nu crește semnificativ șansa unui diagnostic pozitiv). difficile. suis-specific gdh gene yielded 87. However, the clinical significance remains unclear in cases that demonstrate a. 2%) specimens were GDH positive/toxin negative; toxigenic strains were isolated from 21 (4. difficile in the sample, but presence of toxin is unknown. All ribotypes. The staining intensity of GDH-positive samples ranged from light yellow to tan to sepia and was mainly located in the. dacă este pozitiv se confirmă ICD dacă este negativ este foarte probabilă colonizarea cu C. The 2-step algorithm does not use Toxin IC, it uses GDH IC and if positive PCR. Patients with a positive test for CDI without positive results for antigen or toxin should NOT be considered to have meaningful CDI and should NOT be treated. In addition to contributing to Krebs cycle anaplerosis and energy production, GDH function is linked to redox. i. It has been shown to cut the risk of repeat C. The glutamate dehydrogenase (GDH) catalyses the reversible conversion of glutamate into α-ketoglutarate, which initiates amino acid transamination during cheese ripening. Model Overview. According to our validation studies. For many years, it was not at all clear why animals required such complex control. D. With regards to the toxigenicity of C. All G. Thirty‐five samples (18. 5% of discordant cases with known GDH/toxin testing results were GDH positive/toxin negative. TPHA – test specific de confirmare a infectiei cu Treponema pallidum. difficile toxin A/B immunoassay, human stool specimens from patients with diarrhoea (n = 1085) were classified as either GDH positive/toxin negative, or GDH positive/toxin positive. Patients. 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). Further, in both standard. 2–99. difficile. The GDH test is recommended as an initial screening test because of its very high sensitivity [2, 4, 7, 9, 16], reported to be 79. difficile infekció Eredménykiadás Eredménykiadás vagy 3. 1. 2%) specimens. DIFF Quik Chek Complete. GDH assays require 4–6 h from receipt until reportable results are available. Eight samples (2. A positive GDH test alone does not meet the NHSN definition of a C. 9 Cases were assigned to a given hospital based on. . difficile bacteria. difficle GDH antibodies, lmmunoCord C. The GDH test has high sensitivity and. difficile GDH is performed first, and GDH-positive specimens are tested further for toxin production by ELISA [21,22]. GDH testing as a first screening assay performed well compared to culture and/or PCR and was in the range of previously reported sensitivity of 85 to 93% (8-10, 12, 13). difficile. Cytotoxicity assay is considered as the reference method for detecting free toxins (mainly toxin B) in stools. difficile toxin B gene (tcdB) by polymerase chain reaction (PCR). In conclusion, the results suggest that rapid tests for GDH detection are not only suitable for CDI diagnosis as screening tests but also as a single method. If the GDH is negative, CDI can effectively be ruled out due to a greater than 95% sensitivity of the GDH assay. 3% in our study) or positive for both GDH and CDT (7. C. Si tratta di test abbastanza semplici, con una sen-sibilità accettabile (80-95%) e con un breve turn-around time (2 ore), che ne favorisce l’utilizzo in. GDH is negative. difficile test (Cepheid, Sunnyvale, CA, USA) were used to ascertain the toxin/toxigenic status of patients. 5%) and NPV (98. 4. difficile culture/PCR was 93. GDH and EIA testing may be either in parallel (ie, together in the same test) or sequential, if a stand-alone GDH assay is used, followed by an independent EIA toxin A/B test. 1%) confirmed cases, and seven subjects with negative qPCR were considered CDI positive by. T. 3%) were positive for both GDH and toxins, and 23 (13. Such isolates are prone to selective transmission and thus form a challenge to case management. Diff Quik Chek Complete D-EIA provides a rapid and reproducible first-line screening assay for laboratory diagnosis of C. 9–99. Bacteria sau sporii săi sunt clasificate în confirmate (GDH pozitiv și una sau ambele toxine răspândiţi prin intermediul mâinilor personalului medical sau al pozitive – A şi/ sau B, folosind EIA) şi probabile (GDH pozitiv altor persoane care vin în contact cu pacienţii infectaţi sau cu plus legătura epidemiologică definită ca. We calculated sensitivity, specificity, positive and negative predictive values as measures of test performance, as well as local prevalence. sordellii , which produce. difficile infection. difficile but does not have active disease (again, one or the other of tests was a false negative, perhaps related to the density of the organism in stool). In Young Yoo, M. Method. Introducing a random-access screening test resulted in. Introduction. We investigated the validity of this approach in an inpatient adult population. taking a 10-day course of another antibiotic that can treat the C. 1%) had a GDH-positive, toxin-negative EIA result. GDH-positive samples were tested for C. †Positive GDH result, combined with negative toxin (CDAB) result may be arbitrated by molecular testing (NAAT). difficile toxins A and B, was evaluated for its ability to diagnose C. difficile, de aceea testul nu poate face diferenţierea între tulpinele toxigene şi tulpinile non-toxigene de C. Isolates were subcultured to BHI and grown for 72h then tested by tissue culture for the presence of toxin B. Clostridium difficile - GDH - metode și materiale folosite. A GDH positive result, in the absence of concomitant toxin A/B positivity, may be due to the presence of a strain not capable of producing toxins A and B, whereas with a NAAT positive result the presence of a potentially toxigenic. A Clostridium difficile fertőzés kezelése az alábbiak szerint történhet: Az aktuálisan szedett antibiotikum abbahagyása, amennyiben az lehetséges. 6%) patients with a positive NAAT and GDH test and a negative toxin A&B EIA, no antibiotics against C. difficile is currently performed as a two-step process. difficile, de aceea testul nu poate face diferenţierea între tulpinele toxigene şi tulpinile non-toxigene de C. Antimicrobial drugs disrupt the normal intestinal flora, allowing C. Storage and Stability Upon arrival, store kit at -20°C, protected from light. 0:In the post-intervention period, 5. Cases of positive CD PCR, positive GDH, and negative toxin were listed as unclear regarding interpretation. 2A positive GDH result has to be confirmed by a second more specific test detecting toxins. 클로스트리디오이데스 디피실 장염(Clostridioides difficile Infection, CDI)이란 항생제를 투여받는 환자의 장관에 정상 세균총 (colonic flora) 구성이 변화하면서 C. A retrospective study of patients with GDH positive/toxin negative results to determine the probability of detecting toxigenic C. Twelve samples (3. 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. difficile strains express GDH, a positive GDH EIA requires follow-up testing with a toxin EIA and/or a sensitive assay for toxin B (i. Negative Reported as: C difficile toxin assay negative Positive Reported as: Positive by CAll patients who are GDH positive, toxin negative, PCR-negative do not need to remain source-isolated unless there is a confirmed/suspected alternative infective cause for their symptoms; When a CDI positive or GDH positive, toxin negative, PCR-positive patient is transferred or discharged the vacated isolation room must be decontaminated with. 2. diff. difficile assay was completed, on average, in less than 1 h. 0%) only VIDAS GDH positive without toxin confirmation. We subsequently reviewed patient records to describe CD PTP at the time GIPCR was ordered. difficile, and a positive result for GDH in stool marks the existence of C. Results: In the CR, the most commonly used test in the diagnosis of CDI is the C. If this is found in your sample, this means that you have C. 8 CMV Ab IgG: 167. We identified 483 patients with positive CD PCR targets. Ce inseamna acest lucru?Methods. When using a membrane assay, which combines GDH and Toxin A/B tests (see Figure 2: Testing Algorithm 2), samples with either both positive, both negative, or GDH positive toxin negative results can be reported as above. There is a relatively high false-negative rate since 100 to 1000 pg of toxin must be present for the test to be positive . A betegség sokszor az antibiotikumok túlhasználatának eredménye, mert a bélben meghonosodott, az emberi szervezetre ártalmatlan. Apoptosis is an energy-reliant process and demands higher adenosine 5′-triphosphate (ATP) consumption than does the non. Using this algorithm, they found a sensitivity of 84% and specificity of 99. 5 (98. difficile infection event, which requires either a positive NAAT or toxin-based assay. With this three-step approach, results of c. Detectarea enzimei GDH (glutamat dehidrogenaza) Metoda are sensibilitate ridicată , insa specificitate redusă; de aceea poate fi. The cross-reactivity of GDH detection with other cultured Clostridia was reported for one sample in a previous study by Alfa et al. We have added new references and. Stop Solution 1, Premier C. One study even reported that 40% of GDH-positive/toxin AB-negative cases showed positive results in PCR . caudatum cells with ammonia and antibiotics. difficile GDH antigen to just above the assay LoD (10 ng/mL) and just below the assay limit of blank (high negative). Methods: We performed a retrospective cohort study evaluating all C. d Either both immunoassays positive or positive PCR result in GDH positive and toxin negative cases. , Quinn et al. A positive GDH result has to be confirmed by a second more specific test detecting toxins. difficile colonization (the GDH test was positive, but the toxin test was a true negative). e. In May 2022, in the microbiology laboratory of Hospital San Cecilio, we observed three doubtful positive cases in a few days. This approach provides confirmatory results for >90% of specimens submitted for testing. GDH-negative samples are reported as. difficile GDH Sample Diluent/Negative Control, ImmunoCard C difficile GDH Enzyme Conjugate, lmmunoCard Wash Buffer 1, and lmmunoCard Substrate 1. difficile toxin EIAs (toxin). 1) [ 1 ]. 006. For samples with discordant results, PCR testing can then exclude the presence of toxigenic strains in approximately one additional hour. 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 (). It used to be called Clostridium difficile. difficile toxin antigen assay. Presence of either GDH antigen or toxin coupled with presence of C difficile toxin B gene (ie, positive PCR test) is consistent with C difficile infection in a symptomatic patient. difficile. If GDH negative and toxin positive, always a false positive (very rare). Tables 1 and 2 compare the performance of GDH or toxin A/B RDT with the respective EIA. 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. difficile 균이 증식하고, 동시에 독소를 분비하여 발생하는 항생제 관련 설사병 (antibiotic-associated diarrhea, AAD. În cazul unui rezultat pozitiv pentru C. In this study, two chemiluminescent immunoassays (CLIAs), one for GDH and the other for the toxins A. Among 356 GDH positive/toxin negative patients, cultures were performed in 220 cases and toxigenic C. diff Quik Chek Complete; Alere Inc. healthcare-associated (i. The School Aged Surveillance, Age Trends, LTCF Weekly, and LTCF Percent Positivity Reports have been discontinued. bioMérieux's Complete C. • Step 2, as needed: If the specimen tests negative for C. A C. The corrected sensitivity and specificity of the PCR assay. This approach has been advocated recently by Doing et al. difficile assay by the Leeds laboratory as part of an internal evaluation. 85% of samples were available on the day specimens were received and the need for CCA testing was even further reduced to 15% [12, 13, 14]. The GDH Enzymes. Diagnostic testing for Clostridium difficile infection (CDI) may be accomplished through (i) organism detection by anaerobic culture or glutamate dehydrogenase (GDH) immunoassay with subsequent confirmation of toxigenicity, (ii) toxin detection by cell cytotoxicity neutralization assay (CCNA) or enzyme immunoassay (EIA), and (iii) nucleic. bioMérieux's Complete C. A total of 400 samples were submitted during the first period. Diff Quik Chek Complete assay, which tests for the presence of both glutamate dehydrogenase (GDH) and C. Result must be included in mandatory reporting; • If GDH EIA (or NAAT) positive, and toxin EIA negative, then C. 9–99. difficile GDH is performed first, and GDH-positive specimens are tested further for toxin production by ELISA [21,22]. difficile PCR assay and/or repeat GDH/Toxin testing of a subsequent sample if indicated. Of 486 patients, 310 (63. This is the first report where P. In recent years, Plasmodium falciparum histidine-rich protein 2 gene deletion has been reported in India. 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. test for GDH will generally rule out the infection. difficile colonization and may not require therapy but should be placed in enteric isolation regardless of treatment b. The interpretation of a positive GDH and negative toxin assay is difficult. Panel A, black bars, AL group; white bars, RF group; acute fasted and refed groups, not. Samples that are NAAT- or GDH-positive but toxin-negative may represent C. difficile were initiated versus 4/28 (14. 2017. Cytotoxicity assay is considered as the reference method for detecting free toxins (mainly toxin B) in stools. Only a few hepatocytes were GDH-positive in the acute fasted and refed groups. 8% and a positive predictive. GDH detects toxigenic as well as non-toxigenic strains and while it has been recommended as a screening tool in combination with other confirmative tests for GDH-positive samples [13, 14], its sensitivity was reported to be less than optimal [6, 15]. The authors reported intense astrocytic GDH. Twenty C. 098 (95%CI 0. diffidile GDH is a rapid qualitative enzyme immunoassay screening test. has changed. If a sample is positive for GDH but negativeGlutamate dehydrogenase (GDH) is a mitochondrial enzyme that is involved in the metabolism of glutamate to 2-oxoglutarate. If the result is GDH positive a second test is performed to look for toxins that are produced when C. materii fecale (coprorecoltor. Clostridium difficile PCR Severe disease. difficile excretors –Event Requests. We made this assumption based on the increased sensitivity of GDH over toxin EIA and the fact that 99. 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). 16 ng/mL for toxin B, 0. Results indicate that EIAs provide a rapid screening assay for the laboratory diagnosis of CDI but, in GDH-positive and toxins-negative samples, EIA should be always followed by. 3 4 Of note, a few. e. suis–negative samples. difficile GDH antigen. This method comprises inoculating a stool filtrate onto a cell culture and observing a specific cytopathic effect (cell rounding) after 1 or 2. S1 Fig: GDH ELISA. diff? Detection of GDH and toxin in an asymptomatic patient is not specific for disease, as patients may be colonized with C difficile. 71/1000 patient days. difficile glutamate dehydrogenase (GDH)-immunoassay followed by a toxin-immunoassay in positive cases is widely used. C. difficile PCR assay. difficile colonization and may not require therapy but should be placed in enteric isolation regardless of treatment b. We sought to determine if the two-step algorithm (screening GDH and toxin lateral flow assay followed by tcdB PCR) would have adequate clinical performance at a tertiary care center. This homohexameric mitochondrial enzyme has subunits comprised of ~ 500 amino acids in animals. Interestingly, immunostaining results showed that metastatic lymph nodes and liver metastases lesions had higher levels of GDH expression (Figure 2 E and F). Across test arms (i. difficile - GDH, se efectuează gratuit analiza C. The Xpert C. vivax validated by. difficile 균이 증식하고, 동시에 독소를 분비하여 발생하는 항생제 관련 설사병 (antibiotic-associated diarrhea, AAD. A/B. 9%, with a negative predictive value of 98. diff antigen glutamate dehydrogenase (GDH). The C. difficile toxin (high specificity but suboptimal sensitivity) to confirm the diagnosis of CDI. difficile causes disease via toxin production, leading to intestinal mucosal damage. difficile GDH is a qualitative test that detects the C. A true positive (TP) was defined as positivity by CCNA or positivity by LAMP plus another test (GDH, CDT, or the Premier C. FMT is a newer treatment for C.