Performance of laboratory tests for detection for Clostridioides difficile: A multicenter prospective study in Japan.

BACKGROUND: The optimal and practical laboratory diagnostic approach for detection of Clostridioides difficile to aid in the diagnosis of C. difficile infection (CDI) is controversial. A two-step algorithm with initial detection of glutamate dehydrogenase (GDH) or nucleic acid amplification test (NAAT) alone are recommended as a predominant method for C. difficile detection in developed countries. The aim of this study was to compare the performance of enzyme immunoassays (EIA) detecting toxins A and B, NAAT detecting the toxin B gene, and GDH compared to toxigenic culture (TC) for C. difficile as the gold standard, in patients prospectively and actively assessed with clinically significant diarrhea in 12 medical facilities in Japan. METHODS: A total of 650 stool specimens were collected from 566 patients with at least three diarrheal bowel movements (Bristol stool grade 6-7) in the preceding 24 h. EIA and GDH were performed at each hospital, and NAAT and toxigenic C. difficile culture with enriched media were performed at the National Institute of Infectious Diseases. All C. difficile isolates recovered were analyzed by PCR-ribotyping. RESULTS: Compared to TC, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of EIA were 41%, 96%, 75% and 84%, respectively, and for NAAT were 74%, 98%, 91%, and 92%, respectively. In 439 specimens tested with GDH, the sensitivity, specificity, PPV, and NPV were 73%, 87%, 65%, and 91%, and for an algorithm (GDH plus toxin EIA, arbitrated by NAAT) were 71%, 96%, 85%, and 91%, respectively. Among 157 isolates recovered, 75% of isolates corresponded to one of PCR-ribotypes (RTs) 002, 014, 018/018", and 369; RT027 was not isolated. No clear differences in the sensitivities of any of EIA, NAAT and GDH for four predominant RTs were found. CONCLUSION: The analytical sensitivities of NAAT and GDH-algorithm to detect toxigenic C. difficile in this study were lower than most previous reports. This study also found low PPV of EIAs. The optimal method to detect C. difficile or its toxins to assist in the diagnosis of CDI needs further investigation.

Clostridioides (Clostridium) difficile infection burden in Japan: A multicenter prospective study.

Clostridioides (Clostridium) difficile is the leading cause of healthcare-associated infectious diarrhea in the developed world. Retrospective studies have shown a lower incidence of C. difficile infection (CDI) in Japan than in Europe or North America. Prospective studies are needed to determine if this is due lack of testing for C. difficile or a true difference in CDI epidemiology. A prospective cohort study of CDI was conducted from May 2014 to May 2015 at 12 medical facilities (20 wards) in Japan. Patients with at least three diarrheal bowel movements (Bristol stool grade 6-7) in the preceding 24 h were enrolled. CDI was defined by positive result on enzyme immunoassay for toxins A/B, nucleic acid amplification test for the toxin B gene or toxigenic culture. C. difficile isolates were subjected to PCR-ribotyping (RT), slpA-sequence typing (slpA-ST), and antimicrobial susceptibility testing. The overall incidence of CDI was 7.4/10,000 patient-days (PD). The incidence was highest in the five ICU wards (22.2 CDI/10,000 PD; range: 13.9-75.5/10,000 PD). The testing frequency and CDI incidence rate were highly correlated (R2 = 0.91). Of the 146 isolates, RT018/018″ was dominant (29%), followed by types 014 (23%), 002 (12%), and 369 (11%). Among the 15 non-ICU wards, two had high CDI incidence rates (13.0 and 15.9 CDI/10,000 PD), with clusters of RT018/slpA-ST smz-02 and 018"/smz-01, respectively. Three non-RT027 or 078 binary toxin-positive isolates were found. All RT018/018" isolates were resistant to moxifloxacin, gatifloxacin, clindamycin, and erythromycin. This study identified a higher CDI incidence in Japanese hospitals than previously reported by actively identifying and testing patients with clinically significant diarrhea. This suggests numerous patients with CDI are being overlooked due to inadequate diagnostic testing in Japan.

Pathological complete response rate in hormone receptor-negative breast cancer treated with neoadjuvant FEC, followed by weekly paclitaxel administration: A retrospective study and review of the literature.

While tumor size, the presence of inflammatory carcinoma and lymph node involvement are the main prognostic factors of women with locally advanced breast cancer, the prognostic value of the estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 (HER2) status has not been fully clarified. The present study examined the therapeutic efficacy of a neoadjuvant fluorouracil, epirubicin and cyclophosphamide regimen (FEC), followed by weekly paclitaxel and/or trastuzumab administration, in the treatment of hormone receptor-negative breast cancer patients. Between April 2012 and February 2014, 14 patients with hormone receptor-negative local breast cancer (triple-negative type, 9 patients; HER2 type, 5 patients) were included in the study. In all cases, the histological type of the primary cancer was invasive ductal carcinoma. Among the 14 women who received the regimen, 5 presented with stage I cancer (35.7%), 3 with stage IIA (21.4%), 3 with stage IIB (21.4%), 1 with stage IIIB (7.1%) and 2 with stage IIIC (14.3%), according to the American Joint Committee on Cancer staging system. With regard to the tumor-node-metastasis classification, 5 patients were T1N0M0 (35.7%), 3 were T2N0M0 (21.4%), 3 were T2N1M0 (21.4%), 2 were T3N3M0 (14.3%) and 1 was T4N1M0 (7.1%). The pathological response was evaluated using resected tissue following neoadjuvant chemotherapy, according to the criteria established by the Japanese Breast Cancer Society. Patients were classified into pathological responders (grades 2 and 3, 71.4% of all patients) and non-responders (grade 1, 28.6% of all patients). A pathological complete response (pCR) was achieved in 50.0% of all cases (7/14); 44.4% of triple-negative-type cases (4/9) and 60.0% of HER2-type cases (3/5). Hematological and non-hematological toxicity was reversible and manageable. No patients withdrew from treatment, and favorable compliance was achieved. The present study demonstrated that neoadjuvant FEC followed by weekly administration of paclitaxel and/or trastuzumab induces a high pathological response and a high pCR rate in patients with hormone receptor-negative breast cancer. Due to the high clinical benefit rate and acceptable safety profile, this regimen should be considered an acceptable neoadjuvant treatment option for hormone receptor-negative breast cancer.

Examination of the clinical efficacy of eribulin and trastuzumab in HER2-positive recurrent breast cancer.

There are limited studies reported that describe the efficacy of eribulin and trastuzumab in the treatment of recurrent breast cancer. The present study examined the therapeutic efficacy of eribulin and trastuzumab in the treatment of recurrent breast cancer. Between October 2011 and August 2013, 5 recurrent breast cancer patients who were treated with eribulin and trastuzumab were included in the study. The cancer stages in the 5 women who received this regimen were stage IIIB in 1 (20%) and stage IV in 4 (80%). The sites of recurrence were the lung in 3 patients, liver in 2, bone in 1, brain in 1, supraclavicular lymph nodes in 1, infraclavicular lymph nodes in 1 and mediastinal lymph nodes in 1. The median number of prior treatment regimens was 5 (range, 5-11). Complete response was achieved in 0 patients, 1 achieved partial response, 3 had stable disease, and 1 had progressive disease. The overall response rate was 20%, and the clinical benefit rate was 80%. Patients also reported grade 3/4 neutropenia (80.0%). However, hematological toxicity was reversible and manageable. The most common grade 3/4 nonhematological toxicities were fatigue (20.0%), peripheral neuropathy (20.0%) and appetite loss (20.0%). No patients withdrew from treatment, and favorable compliance was achieved in the study. The results indicated that eribulin and trastuzumab have the potential to be one of the drugs for treatment of recurrent breast cancer.

Pathological response rate in hormone-positive breast cancer patients treated with neoadjuvant FEC and triweekly docetaxel: a case series.

We recently reported that neoadjuvant 5-FU, epirubicin, and cyclophosphamide (FEC) followed by weekly paclitaxel and/or trastuzumab induced a high pathological complete response (pCR) rate in hormone-negative patients. The present study examined the therapeutic efficacy of neoadjuvant FEC followed by triweekly docetaxel and/or trastuzumab in the treatment of hormone-positive patients. Between February 2012 and December 2013, 16 hormone-positive patients with local breast cancer (luminal A type: six patients; luminal B type: two patients; luminal HER2 type: eight patients) were included in the study. The histological type of the primary cancer was invasive ductal carcinoma in all patients. The cancer stages in the 16 women who received this regimen were stage I in five (31.3%), IIA in four (25.0%), IIB in five (31.3%), IIIB in one (6.3%), and IIIC in one (6.3%). Regarding clinical TNM classification, five patients were T1N0M0, one was T1N1M0, three were T2N0M0, five were T2N1M0, one was T3N2M0, and one was T4N0M0. The pCR was evaluated using resected tissue after neoadjuvant chemotherapy according to the evaluation criteria of the Japanese Breast Cancer Society. Patients were classified into pathologic responders (grade 2: 50.0% of all patients: 2/6 of luminal A type; 6/8 of Luminal HER2 type) and nonresponders (grades 0 and 1: 50.0% of all patients: 4/6 of luminal A type; 2/2 of luminal B type; 2/8 of luminal HER2 type) according to the grade of the tumor. The pCR rate was 0%. Hematologic and nonhematologic toxicity was reversible and manageable. This study demonstrated that neoadjuvant FEC followed by triweekly docetaxel and/or trastuzumab did induce a high pathologic response in luminal HER2 type, but not in luminal A and B types, and did not induce a high pCR rate in the hormone-positive patients.