ABSTRACT
Abstract. Clostridium difficile infection (CDI) is one of the most common nosocomial infections in Thailand and worldwide. The clinical spectrum ranges from annoy- ing diarrhea to severe life-threatening disease. Enzyme-linked immunofluorescent assay for cytotoxins A/B (cytotoxins A/B ELFA), which has been widely used in our institute, generally is considered as having low sensitivity for diagnosis of CDI. The study was a prospective evaluation of a novel two-step diagnostic algorithm, in which the first step involved concurrent cytotoxins A/B ELFA and enzyme immunoassay for glutamate dehydrogenase (GDH EIA) for CDI, followed by PCR assay of tcdA and tcdB in samples with discordant results. Of the 91 adult patients (37 males and 54 females, mean age of 60.0 ± 19.5 years) with suspected CDI hospitalized at King Chulalongkorn Memorial Hospital, Bangkok, Thailand from December 2012 to February 2013, 22 were diagnosed with CDI by the gold standard PCR test for tcdA and tcdB, among whom 21 were positive by GDH EIA, accounting for a sensitivity of 95%. Of the 69 patients without CDI, GDH EIA was negative in 46 patients, accounting for a specificity of 67%. The positive predic- tive value (PPV), negative predictive value (NPV) and accuracy of GDH EIA was 48%, 98% and 74%, respectively, whereas sensitivity, specificity, PPV, NPV, and accuracy of cytotoxins A/B ELFA was 73%, 96%, 84%, 92% and 92%, respectively. Some 30% of specimens required the more expensive PCR assay. However, this two-step protocol detected 20% more patients with CDI than the currently used cytotoxins A/B ELFA method.
Subject(s)
Bacterial Proteins/genetics , Bacterial Toxins/analysis , Clostridioides difficile/genetics , Enterocolitis, Pseudomembranous/diagnosis , Glutamate Dehydrogenase/analysis , Adult , Aged , Clostridioides difficile/enzymology , Clostridium Infections/diagnosis , Cross Infection , Enzyme-Linked Immunosorbent Assay , Feces/enzymology , Feces/microbiology , Female , Humans , Immunoenzyme Techniques , Male , Mass Screening , Middle Aged , Polymerase Chain Reaction/methods , Prospective Studies , Sensitivity and Specificity , ThailandABSTRACT
BACKGROUND: Currently, in established antibiotic era, there is a widespread and increasing use of broad-spectrum antibiotics. Clostridium difficile, one of the troublesome intruders, flourishes when normal gut flora is altered by antibiotics. C. difficile is recognized as a frequent and leading cause of antibiotic-associated diarrhea and colitis. It causes substantial morbidity and mortality in hospitalized patients. OBJECTIVE: The present study was aimed at determining patient characteristics, clinical features, treatment, and outcomes of C. difficile-associated disease (CDAD) in hospitalized patients at King Chulalongkorn Memorial Hospital, Bangkok, Thailand. MATERIAL AND METHOD: From 2002 to 2005, 88 patients with positive latex immunoassay for C. difficile toxin A were identified. Data from medical records of 56 patients were available for analysis. RESULTS: Of 56 patients, there were 28 males and 28 females, with the mean age of 47.39 years (range: 4 months to 93 years). 50 (89.3%) patients had underlying illnesses with hematological malignancies (14 patients, 25%) and solid tumors (15 patients, 26.8%) being the most common. All patients had a history of antibiotic use including current (17 patients, 30.4%), recent (16 patients, 28.6%), or both current and recent uses (23 patients, 41.1%). Cephalosporins and carbapenems were the two most commonly prescribed antibiotics. 25 (44.6%) patients were receiving either omeprazole or ranitidine. 12 (21.4%) patients had received chemotherapy within two months before CDAD diagnosis. Of 50 stool specimens examined, only 26 (52%) had white or red blood cells. Colonoscopy was performed in only three patients, and pathological findings revealed non-specific colitis. Oral metronidazole, intravenous metronidazole, and vancomycin were prescribed for CDAD treatment in 38 (67.9%), 4 (7.1%), and 2 (3.6%) patients, respectively. 8 (14.3%) patients had no specific treatment, and the offending antibiotic was not discontinued in three of them. An overall initial response rate was 66.7%. 2 patients relapsed after metronidazole treatment. CONCLUSION: The present study is the first in Southeast Asia to describe the decreased initial response rate of metronidazole treatment of CDAD. The reasons for this relatively poor response in the presented patients need to be determined in a future study.
