Rapid and accurate diagnosis of Clostridium difficile infection by real-time polymerase chain reaction.

BACKGROUND/AIMS: The incidence and severity of Clostridium difficile infection (CDI) have increased worldwide, resulting in a need for rapid and accurate diagnostic methods. METHODS: A retrospective study was conducted to compare CDI diagnosis methods between January 2014 and December 2014. The stool samples, which were obtained in presumptive CDI patients, were compared for their diagnostic accuracy and rapidity, including real-time polymerase chain reaction (PCR) of toxin genes, C. difficile toxin assay, and culture for C. difficile. RESULTS: A total of 207 cases from 116 patients were enrolled in this study and 117 cases (56.5%) were diagnosed as having CDI. Among the 117 cases, the sensitivities of real-time PCR, C. difficile toxin assay, and culture for C. difficile were 87.2% (102 cases; 95% CI, 80.7%-92.8%), 48.7% (57 cases; 95% CI, 41.0%-59.8%), and 65.0% (76 cases; 95% CI, 60.2%-78.5%), respectively (P<0.005). Notably, 34 cases (29.0%) were diagnosed with CDI by real-time PCR only. The time required to obtain results was 2.27 hours (136.62±82.51 minutes) for real-time PCR, 83.67 hours (5,020.66±3,816.38 minutes) for toxin assay, and 105.79 hours (6,347.68±3,331.46 minutes) for culture (P<0.005), respectively. CONCLUSIONS: We confirmed that real-time PCR of toxin genes is the most effective diagnostic method for accurate and early diagnosis of CDI. It also helps to diagnose hypervirulent CDI, such as ribotype 027 infection.

Can we predict when to start renal replacement therapy in patients with chronic kidney disease using 6 months of clinical data?

PURPOSE: We aimed to develop a model of chronic kidney disease (CKD) progression for predicting the probability and time to progression from various CKD stages to renal replacement therapy (RRT), using 6 months of clinical data variables routinely measured at healthcare centers. METHODS: Data were derived from the electronic medical records of Ajou University Hospital, Suwon, South Korea from October 1997 to September 2012. We included patients who were diagnosed with CKD (estimated glomerular filtration rate [eGFR] < 60 mL·min-1·1.73 m-2 for ≥ 3 months) and followed up for at least 6 months. The study population was randomly divided into training and test sets. RESULTS: We identified 4,509 patients who met reasonable diagnostic criteria. Patients were randomly divided into 2 groups, and after excluding patients with missing data, the training and test sets included 1,625 and 1,618 patients, respectively. The integral mean was the most powerful explanatory (R2 = 0.404) variable among the 8 modified values. Ten variables (age, sex, diabetes mellitus[DM], polycystic kidney disease[PKD], serum albumin, serum hemoglobin, serum phosphorus, serum potassium, eGFR (calculated by Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI]), and urinary protein) were included in the final risk prediction model for CKD stage 3 (R2 = 0.330). Ten variables (age, sex, DM, GN, PKD, serum hemoglobin, serum blood urea nitrogen[BUN], serum calcium, eGFR(calculated by Modification of Diet in Renal Disease[MDRD]), and urinary protein) were included in the final risk prediction model for CKD stage 4 (R2 = 0.386). Four variables (serum hemoglobin, serum BUN, eGFR(calculated by MDRD) and urinary protein) were included in the final risk prediction model for CKD stage 5 (R2 = 0.321). CONCLUSION: We created a prediction model according to CKD stages by using integral means. Based on the results of the Brier score (BS) and Harrel's C statistics, we consider that our model has significant explanatory power to predict the probability and interval time to the initiation of RRT.

A Case of Hepatocellular Carcinoma Presenting as a Gingival Mass.

Oral metastatic tumor, which is uncommon and represents less than 1% of malignant oral neoplasms, usually arises from a primary mucosal or cutaneous cancer located in the head and neck regions. Metastasis of hepatocellular carcinoma (HCC) to the oral cavity, especially to gingiva, is extremely rare. A 50-year-old man, who was a chronic alcoholic and hepatitis B virus carrier, presented with abdominal distension and weight loss for the past 3 months. Three-phased contrast-enhanced abdominal CT revealed numerous conglomerated masses in the liver, suggesting huge HCCs arising in the background of liver cirrhosis with a large amount of ascites. He complained of recurrent profuse bleeding from the left upper gingival mass. A facial CT revealed an oral cavity mass destructing the left maxillary alveolar process and hard palate, which was diagnosed as metastatic HCC by an incisional biopsy. Herein, we report a case of metastatic HCC to the gingiva.

Risk factors for delayed post-polypectomy bleeding.

BACKGROUND/AIMS: Among the many complications that can occur following therapeutic endoscopy, bleeding is the most serious, which occurs in 1.0-6.1% of all colonoscopic polypectomies. The aim of this study was to identify risk factors of delayed post-polypectomy bleeding (PPB). METHODS: We retrospectively reviewed the data of patients who underwent colonoscopic polypectomy between January 2003 and December 2012. We compared patients who experienced delayed PPB with those who did not. The control-to-patient ratio was 3:1. The clinical data analyzed included polyp size, number, location, and shape, patient' body mass index (BMI), preventive hemostasis, and endoscopist experience. RESULTS: Of 1,745 patients undergoing colonoscopic polypectomy, 21 (1.2%) experienced significant delayed PPB. We selected 63 age- and sex-matched controls. Multivariate logistic regression analysis showed that polyps >10 mm (odds ratio [OR], 2.605; 95% confidence interval [CI], 1.035-4.528; P=0.049), a pedunculated polyp (OR, 3.517; 95% CI, 1.428-7.176; P=0.045), a polyp located in the right hemicolon (OR, 3.10; 95% CI, 1.291-5.761; P=0.013), and a high BMI (OR, 3.681; 95% CI, 1.876-8.613; P=0.013) were significantly associated with delayed PPB. CONCLUSIONS: Although delayed PPB is a rare event, more caution is needed during colonoscopic polypectomies performed in patients with high BMI or large polyps, pedunculated polyps, or polyps located in the right hemicolon.

Recurrence patterns of combined hepatocellular-cholangiocarcinoma on enhanced computed tomography.

OBJECTIVE: To determine whether the computed tomographic (CT) findings of primary and recurrent combined hepatocellular-cholangiocarcinoma (HCC-CC) can predict the main tumor component on histopathologic examination, and to describe the recurrence patterns of HCC-CC after surgery. METHODS: Preoperative and postoperative CT findings of 12 HCC-CC patients who underwent curative surgery were retrospectively reviewed. The main features of the primary and recurrent tumors on CT and the pathological findings were classified as hepatocellular carcinoma (HCC)-dominant and cholangiocarcinoma (CC)-dominant groups. The concordance between the preoperative CT features and the initial pathological findings was evaluated using kappa statistics. The survival periods of the HCC-dominant and the CC-dominant group were compared using the Mann-Whitney U test. RESULTS: In 11 (91.7%) of 12 patients, the main CT features of HCC-CC were in strong agreement with main pathological findings (kappa = 0.824). The most common site of recurrence was the remnant liver. In 3 cases, only nodal metastasis was noted. The mean survival period was significantly longer in the HCC-dominant group than in the CC-dominant group of recurrent tumor (P = 0.016). CONCLUSIONS: Contrast-enhanced CT scanning can predict the dominant component of primary and recurrent HCC-CC. This capability can optimize treatment strategy for the patient with recurrent HCC-CC.

Hepatic macrosteatosis: predicting appropriateness of liver donation by using MR imaging--correlation with histopathologic findings.

PURPOSE: To retrospectively evaluate the diagnostic performance of magnetic resonance (MR) imaging in predicting the appropriateness of liver donation in potential living liver donors by using histopathologic results as the reference standard. MATERIALS AND METHODS: This study was approved by institutional review board; all patients gave informed consent for the use of MR data for future research. Fifty-seven potential liver donors (40 male, 17 female; age range, 17-57 years; mean age, 32 years) underwent dual-echo 1.5-T MR imaging. Two radiologists qualitatively graded each MR image, with consensus for disagreements. Livers were assigned one of three degrees of hepatic steatosis on the basis of changes in hepatic signal intensity (SI) between in-phase and opposed-phase images. For quantitative analysis, a third radiologist calculated mean hepatic and mean splenic SI by averaging 25 hepatic regions of interest and three splenic regions of interest. Relative SI decrease (RSID) in the liver on opposed-phase images compared with in-phase images was calculated. Linear regression analysis was used to correlate RSID with the degree of total steatosis, macrosteatosis, and microsteatosis. Diagnostic performance for predicting the appropriateness of liver donation was analyzed. RESULTS: Histologic findings of macrosteatosis resulted in 52 patients being categorized as appropriate donors, with the remaining five being categorized as inappropriate donors. RSID was correlated with total steatosis (r = 0.850). When the RSID criterion for inappropriateness of liver donation was set at 20%, the sensitivity, specificity, and accuracy were 100%, 92.3%, and 93%, respectively. When RSID was used, four livers that had been misclassified as inappropriate for transplantation were found to have microsteatosis of various degrees and a less than moderate degree of macrosteatosis at histologic analysis. Qualitative and quantitative analyses were comparably accurate. CONCLUSION: When an RSID criterion of less than 20% was used, dual-echo MR imaging facilitated the correct prediction of appropriateness of liver donation in 53 of 57 patients.