Diagnostic utilities of a fully automated molecular test for toxigenic Clostridium difficile.

Laboratory underdiagnosis of toxigenic Clostridium difficile can lead to inappropriate management of C. difficile infection (CDI). A fully automated molecular test (FAMT), BD MAX, and enzyme immunoassays for C. difficile glutamate dehydrogenase (GDH) and for toxin A/B antigen test were evaluated using clinical specimens. Laboratory analysis of 231 fecal specimens from patients suspected with CDI, indicated that the sensitivity (Sn), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV) of FAMT was 98.1%, 98.9%, 96.3%, and 99.4%, while that of toxin A/B antigen was 52.8%, 100.0%, 100.0%, and 87.7%, respectively, compared to toxigenic culture. Sn, Sp, PPV, and NPV of GDH test compared to toxigenic culture was 92.5%, 94.4%, 83.1%, and 97.7%, respectively. FAMT can support the accurate laboratory diagnosis of toxigenic C. difficile and be an effective tool for appropriate treatment of CDI.

Distribution and characterization of Clostridium difficile isolated from dogs in Japan.

We collected 204 nondiarrhoeic canine fecal samples and isolated 68 Clostridium difficile strains from 62 of these samples. Strains were grouped into 29 PCR ribotypes. Only 47% of the strains were toxigenic.

Characteristics of colonoscopic findings in the very elderly.

AIM: To determine the incidence and endoscopic types of colorectal lesions diagnosed with colonoscopy in elderly patients. METHODS: Consecutive Japanese patients who underwent colonic endoscopy between 1994 and 2007 (n = 5145; 2245 men and 2900 women, age 20-101 years) were examined retrospectively. Correlations between age, sex and number of lesions were analyzed. RESULTS: The incidence of advanced tumors was significantly correlated with increasing age in men (P = 0.02), and tumors were detected mainly in the sigmoid colon and rectum in both sexes. Right-sided colon cancer was significantly more common in women compared with men (P < 0.001). Polyps were detected throughout the colon, and their incidence was correlated significantly with increasing age in women (P = 0.01). Diverticula were frequently detected in the ascending and sigmoid colon in both sexes. Left-sided diverticula were significantly more common in women compared with men (P < 0.001). Lateral spreading tumors were detected mainly in the cecum in both sexes. Though the number of cases with angioectasia was small, angioectasia was slightly more common in the cecum and the ascending colon in women. CONCLUSIONS: In the present study, the incidence of advanced tumors correlated with increasing age in men, and right-sided cases were significantly more common in women than in men. The incidence of polyps correlated with increasing age in women. Left-sided diverticula were significantly more common in women than in men. Geriatr Gerontol Int 2016; 16: 1319-1323.

Genetic relatedness between Japanese and European isolates of Clostridium difficile originating from piglets and their risk associated with human health.

Clostridium difficile colonization in pig intestine has been a public health concern. We analyzed C. difficile prevalence among piglets in Japan to clarify their origin and extent of the associated risk by using molecular and microbiological methods for both swine and human clinical isolates and foreign isolates. C. difficile was isolated from 120 neonatal piglet fecal samples. Toxin gene profile, antimicrobial susceptibilities, PCR ribotype, and multiple-locus variable-number tandem-repeat analysis (MLVA) type of swine isolates were determined and compared with those of human clinical and foreign isolates. One-hundred C. difficile strains were isolated from 69 (57.5%) samples, and 61 isolates (61%) were toxin gene-positive. Some isolates were resistant to antimicrobials, contributing to antibiotic-associated diarrhea by C. difficile. These results suggest that C. difficile, prevalent among Japanese pigs, is a potential risk for antibiotic-associated diarrhea. Furthermore, PCR ribotype 078 (12 isolates), which has been linked to multiple outbreaks worldwide, was the third-most frequently isolated of the 14 PCR ribotypes identified. Moreover, MLVA revealed that all 12 PCR ribotype 078 isolates were genetically related to European PCR ribotype 078 strains found in both humans and pigs. To date, in Japan, many breeding pigs have been imported from European countries. The genetic relatedness of C. difficile isolates of Japanese swine origin to those of European origin suggests that they were introduced into Japan via imported pigs.

Significant association between hypolipoproteinemia(a) and lifetime risk of cancer: an autopsy study from a community-based Geriatric Hospital.

BACKGROUND: Our recent study showed that a low lipoproteinemia(a) [Lp(a)] level was a risk factor for cancer and all-cause deaths. The purpose of this study was to verify the role of the Lp(a) level on cancer among consecutive autopsy cases. METHODS: The subjects consisted of 1354 cases (775 men and 579 women). The average age at death was 79.9 years. Hypolipoproteinemia(a) was defined as an Lp(a) level of below 80 mg/L. Overall, 62.3% of the subjects had suffered from at least one to a maximum of five malignancies throughout their lives. The most frequent type of malignancy was gastric cancer, followed by leukemia, lung cancer, and colon cancer. RESULTS: The cancer-bearing status decreased linearly according to the Lp(a) level in both men and women (P=0.01 and P<0.001, respectively). The median Lp(a) level was significantly lower among the cases with hepato-biliary-pancreatic cancers or hematopoietic malignancy, but was higher among cases with lung cancer, especially lung adenocarcinoma. Hypolipoproteinemia(a) was a significant risk factor for any origins of cancer, with an odds ratio of 1.94 (95% CI, 1.45-2.60; P<0.001). It was also a risk factor for hepato-biliary cancers and leukemia, but it was a protective factor for lung cancer. CONCLUSIONS: Our findings suggested hypolipoproteinemia(a) would be a significant risk factor for cancer except lung cancer. This study complements our previous study showing that hypolipoproteinemia(a) would increase the lifetime risk of cancer other than lung cancer.

Immunoprotective effects of oral intake of heat-killed Lactobacillus pentosus strain b240 in elderly adults: a randomised, double-blind, placebo-controlled trial.

Oral intake of Lactobacillus pentosus strain b240 (b240) has been shown to enhance the secretion of salivary secretory IgA in elderly adults. However, its clinical benefits remain to be determined. We tested the hypothesis that b240 exerts a protective effect against the common cold in elderly adults. The design of the present study was a randomised, double-blind, placebo-controlled trial (RCT) with parallel three-group comparison. For this purpose, 300 eligible elderly adults were randomly allocated to one of three groups, namely a placebo, low-dose or high-dose b240 group. Participants in the low-dose and high-dose b240 groups were given tablets containing 2 × 10(9) or 2 × 10(10) cells, respectively, of heat-killed b240, while those in the placebo group were given tablets without b240. Each group consumed their respective tablets once daily for 20 weeks. The common cold was assessed on the basis of a diary. Change in quality of life was evaluated using the SF-36. Of the total participants, 280 completed the 20-week RCT. The accumulated incidence rate of the common cold was 47·3, 34·8 and 29·0 % for the placebo, low-dose b240 and high-dose b240 groups, respectively (P for trend = 0·012). Lower incidence rates were consistently observed throughout the experimental period in the b240 groups (log-rank test, P= 0·034). General health perception, as determined by the SF-36®, dose-dependently increased in the b240 groups ( P <0·025). In conclusion, oral intake of b240 significantly reduced the incidence rate of the common cold in elderly adults, indicating that b240 might be useful in improving resistance against infection through mucosal immunity.

Molecular and microbiological characterization of Clostridium difficile isolates from single, relapse, and reinfection cases.

In this study, we investigated the correlation between the microbiological characteristics of Clostridium difficile clinical isolates and the recurrence of C. difficile-associated disease (CDAD). Twenty C. difficile isolates recovered from 20 single infection cases and 53 isolates from 20 recurrent cases were analyzed by pulsed-field gel electrophoresis (PFGE) and PCR ribotyping, and the cytotoxicity, antimicrobial susceptibility, and sporulation/germination rates of the isolates were examined. Recurrent cases were divided into relapse or reinfection cases by the results of C. difficile DNA typing. Among the 20 recurrent cases, 16 cases (80%) were identified to be relapse cases caused by the initial strain and the remaining 4 cases (20%) were identified to be reinfection cases caused by different strains. All 73 isolates were susceptible to both vancomycin and metronidazole, but resistance against clindamycin, ceftriaxone, erythromycin, and ciprofloxacin was found in 87.7%, 93.2%, 87.7%, and 100% of the isolates, respectively. No correlations between DNA typing group, cytotoxicity, and sporulation rate of isolates and infection status, i.e., single, relapse, or reinfection, were observed. However, the isolates recovered from relapse cases showed a significantly higher germination rate when incubated in medium lacking the germination stimulant sodium taurocholate. These results indicate that the germination ability of C. difficile may be a potential risk factor for the recurrence of CDAD.

Evaluation of a simultaneous detection kit for the glutamate dehydrogenase antigen and toxin A/B in feces for diagnosis of Clostridium difficile infection.

Rapid detection kits for toxin A/B in feces are widely used as a diagnostic tool for Clostridium difficile infection (CDI). Their low sensitivity, however, has been considered a problem. In this study, we evaluated a new rapid diagnostic kit for simultaneous detection of the glutamate dehydrogenase (GDH) antigen and toxin A/B, C. DIFF QUIK CHEK COMPLETE. A total of 60 stool specimens from 60 patients with antibiotic-associated diarrhea were examined. Using C. difficile culture as the reference method, the GDH portion of this kit indicated a sensitivity, specificity, and negative predictive value of 100, 93.3, and 100%, respectively. The toxin A/B portion showed a sensitivity and specificity of 78.6 and 96.9%, respectively, compared to the culture results of toxin B-positive C. difficile (toxigenic culture). Of the 23 specimens that showed "dual positives" for GDH and toxin A/B, 22 were toxigenic culture positive, whereas C. difficile culture was negative in all the 28 specimens that showed "dual negatives" for GDH and toxin A/B. Of the nine "GDH-positive and toxin A/B-negative" specimens, six exhibited positive results by toxigenic culture. Results showing "dual positives" and "dual negatives" for GDH and toxin A/B can be reported as "true positive" and "true negative," respectively, whereas additional testing for confirmation, such as toxigenic culture, is required for specimens with discrepant results. Diagnostic algorithms, utilizing the simultaneous detection kit for GDH and toxin A/B as an initial screening test, may be useful for accurate and efficient diagnosis of CDI as well as the control of healthcare-associated infections.

Survey on geriatricians' experiences of adverse drug reactions caused by potentially inappropriate medications: commission report of the Japan Geriatrics Society.

AIM: The Japan Geriatrics Society (JGS) developed the guidelines for medical treatment and its safety in the elderly and the list of potentially inappropriate medication use, a Japanese version of the Beers list, in 2005. The JGS working group in collaboration with the Japan Broadcasting Corporation conducted the survey to geriatricians to investigate their experiences of adverse drug reactions (ADR) caused by potentially inappropriate medications. METHODS: In September 2008, the survey mails were sent to all the JGS certified geriatricians (n=1492). The questionnaire consisted of 1 year of experiences of ADR of any type, past experiences of ADR by the use of antipsychotic benzamides, hypnotic benzodiazepines, digoxin (≥0.15 mg/day), vitamin D3 (alfacalcidol≥1.0 µg/day) and additional drugs, and their attitudes to reduce the dose/number of drugs for the prevention of ADR. RESULTS: A total of 425 geriatricians responded (response rate 29%). Seventy-two percent experienced ADR within 1 year. Past experiences of ADR were reported by 79% for antipsychotic benzamides, 86% for hypnotic benzodiazepines, 70% for digoxin and 37% for vitamin D3. Free responses included frequent ADR by non-steroidal anti-inflammatory, antihypertensive, antiplatelet, anti-arrhythmic, antidiabetic and antidepressant drugs. Reduction of drugs for ADR prevention was attempted by 93%. CONCLUSION: This survey showed that most geriatricians experience ADR and take preventive measures for ADR. The results can be used for education and the development of new guidelines.

A 25-year trace of methicillin-resistant Staphylococcus aureus dissemination in a geriatric hospital in Japan.

We analyzed 218 strains of methicillin-resistant Staphylococcus aureus (MRSA) isolated from the septicemia patients in a geriatric hospital for 25 years. These strains were classified into 11 major DNA types, A through K, and 27 minor types. The strains belonging to group A and B isolated before 1990 were susceptible to imipenem (IPM), fluoroquinolone, and most other antibiotics tested, except that they were markedly resistant to gentamicin. Strains mostly isolated in 1985 and thereafter were classified into group C through K, and they were mainly resistant to IPM, fluoroquinolones, and clindamycin. Analysis of the MRSA marker gene, staphylococcal cassette chromosome mec (SCCmec), of these strains revealed that the strains in groups A and B had mainly type IV and type I, respectively, and that strains in groups C through J had mainly type II. These results suggested that the strains holding type II SCCmec were resistant to IPM, fluoroquinolone, and clindamycin and they were dominant-resistant type after late 1980s. The antibiotic resistance profiles of MRSA dramatically changed during late 1980s, and these were correlated with the SCCmec types. The lesson from this study would be that consistent execution of surveillance study is needed to update the resistant profiles.

Trends of beta-lactam antibiotic susceptibility in blood-borne methicillin-resistant Staphylococcus aureus (MRSA) and their linkage to the staphylococcal cassette chromosome mec (SCCmec) type.

We investigated trends of beta-lactam antibiotic susceptibility in a total of 218 strains of blood-borne methicillin-resistant Staphylococcus aureus (MRSA) isolated from 1978 through 2002 at a middle-size geriatric hospital in Tokyo; the strains were classified by the MRSA marker, staphylococcal cassette chromosome mec (SCCmec). The minimum growth inhibitory concentration (MIC) of cloxacillin at which 50% of the strains were inhibited (MIC50) was 2 microg/ml in the strains isolated in 1978-1984 and 32 to 64 microg/ml in the strains isolated subsequently. Similarly, the MIC50 values of cefazolin and imipenem in the 1978-1984 isolates were 16 and

Trends in the gentamicin and arbekacin susceptibility of methicillin-resistant Staphylococcus aureus and the genes encoding aminoglycoside-modifying enzymes.

It is generally accepted that methicillin-resistant Staphylococcus aureus (MRSA) is also resistant to aminoglycoside antibiotics. We investigated trends of gentamicin and arbekacin susceptibilities and the prevalence of the genes encoding aminoglycoside-modifying enzymes (AMEs) for a total of 218 strains of MRSA isolated from blood specimens obtained from 1978 through 2002 in one hospital. The minimum inhibitory concentrations of gentamicin at which 50% of the strains were inhibited (MIC(50)) were > or =128 and 32 microg/ml for isolates obtained from 1978 to 1984 and from 1985 to 1989, respectively, and 0.5 microg/ml for isolates obtained from 1990 to 2002. The MIC(90) of gentamicin was consistently > or =128 microg/ml. Investigation of the occurrence of AME revealed that the MIC(50) of gentamicin was highly correlated with the presence of aac(6')/aph(2'') encoding aminoglycoside acetyl/phosphotransferase. The MIC(50) of arbekacin was 2 microg/ml for strains isolated in 1978-1984 and

[Usefulness of immunological detection of both toxin A and toxin B in stool samples for rapid diagnosis of Clostridium difficile-associated diarrhea].

Toxin detection from stool specimens is critical for the diagnosis of Clostridium difficile-associated diarrhea (CDAD). In Japan, only two toxin detection kits targeting toxin A alone are commercially available. We evaluated ImmunoCard Toxin A & B (ImmunoCard), based on enzyme immunoassay for the rapid detection of both C. difficile toxins A and B in stool specimens, compared to a toxin A detection kit (Uniquick) and cytotoxin assay. C. difficile was also cultured from stool specimens and the toxin production type of C. difficile isolates was identified by PCR analysis. Compared to cytotoxin assay, ImmunoCard sensitivity was 86.2%, specificity 93.8%, positive predictive value 91.8%, and negative predictive value 89.4% (n = 146). Sensitivity was significantly higher than that of Uniquick (60.0%, p = 0.0016). ImmunoCard detected 90.6% of cytotoxin positive specimens with isolated toxin A-positive, toxin B-positive C. difficile strains (Uniquick; 67.9%, p = 0.008) and 70.0% of these with isolated toxin A-negative, toxin B-positive C. difficile strains. Although ImmunoCard was slightly less sensitive than cytotoxin assay, it requires no special equipment and completes the entire test in up to 20 min. ImmunoCard thus appears very useful in the rapid diagnosis of CDAD in the clinical laboratory. Kits for the detection of both C. difficile toxins A and B should be immediately introduced into Japan to ensure the correct diagnosis of CDAD and infection control.