Significance of a polymerase chain reaction method in the detection of Clostridioides difficile.

OBJECTIVE: Clostridioides difficile (CD) is the most common cause of nosocomial diarrhea. Detection of CD toxin in patients' faecal samples is the traditional rapid method for the diagnosis of CD infection. Various testing algorithms have been proposed: an initial screening test using a rapid test, and a confirmatory test (cytotoxicity neutralization assay, toxigenic culture, nucleic acid amplification test) for discordant results. The aim of this study was to evaluate the effectiveness of a two-step algorithm using an immunochromatographic test followed of a polymerase chain reaction (PCR). METHODS: The specimens have been tested according to the following schedule: 1) Step one: All samples were tested for detection of glutamate dehydrogenase antigen (GDH) and toxin A/B using the C. diff QUIK CHEK Complete test. All GDH and toxins positive results were considered CD positives; 2) Step two: When the results were discrepant (only GDH+ or toxins+), the samples were confirmed using the PCR test BD MAX Cdiff. All PCR positive results were considered CD positives. RESULTS: A total of 2,138 specimens were initially tested. 139 were positive for GDH and toxins. 160 discrepant results (148 GDH+ and 12 toxins+) were tested by PCR, 117 were positive (107/148 GDH+ and 10/12 toxins+). CONCLUSIONS: The implementation of a PCR method showed an increase de 117 positive results (73.1% of discrepant). Considering the sensitivity of C.diff QUIK CHEK (instructions of manufacturer), the GDH discrepant results may be false negatives, y the samples PCR and toxins positives may be real positives results.

[Epidemiology and etiology of vulvovaginal candidiasis in Spanish and immigrants' women in Fuenlabrada (Madrid)]. / Epidemiología y etiología de la candidiasis vaginal en mujeres españolas e inmigrantes en Fuenlabrada (Madrid).

OBJECTIVE: Vulvovaginal candidiasis (VVC) is a common vaginal infection. Risk factors include diabetes, antibiotic use and pregnancy. Candida albicans is the most common species identified but non-C. albicans species appear to be more commonly associated with VVC in some Asian and African countries. We had studied the distribution of Candida species in Spanish and immigrants' women residents in Spain. METHODS: Retrospective study of vaginal yeast cultures between 2015 and 2018. RESULTS: A total of 2,283 vaginal yeast cultures were collected. Candida spp. was detected in 25.7% from Spanish women and in 28.5% from immigrants (no significant differences). Immigrants have higher rates of vaginal candidiasis compared other studies in Spain. C. albicans was the most common species isolated (82.4%). CONCLUSIONS: There were no differences in vaginal candidiasis rate between Spanish and immigrants' women. Immigrants consulted proportionally more compared with the Spanish women.

[Colonization rates by Streptococcus agalactiae in Spanish and foreign pregnant women in the Fuenlabrada University Hospital]. / Tasas de colonización por Streptococcus agalactiae en gestantes españolas y extranjeras en el Hospital Universitario de Fuenlabrada.

OBJECTIVE: In pregnant women, the rectovaginal colonization by Streptococcus agalactiae (GBS) is related with geographic area of origin (6.5% to 36%). It was analysed GBS carriage in pregnant women in 2012-2014 in our hospital. METHODS: Observational retrospective study about GBS isolates from rectovaginal samples (RVS) and urine cultures of Spanish and immigrant pregnant women in 2012-2014. It was considered only a single isolation for patient. There were excluded women with GBS in urine samples of RVS study. RESULTS: A total of 4,648 Spanish and 1,405 immigrant women were analysed. GBS was detected in urine samples in 231 Spanish (5%) and 106 immigrant (7.6%). A total of 5,716 RVS were analysed, GBS was detected in 10.5% of Spanish women and in 18.9% of immigrant women. CONCLUSIONS: The overall colonization in immigrant women is higher than in Spanish with the exception of Asian women. Cases of GBS detected in urine samples might serve as a possible explanation for the high rate of GBS carriage.

Prevalence and distribution of hepatitis C virus genotypes in Spain during the 2000-2015 period (the GEHEP 005 study).

We report the largest study on the prevalence and distribution of HCV genotypes in Spain (2000-2015), and we relate them with clinical, epidemiological and virological factors. Patients from 29 hospitals in 10 autonomous communities (Andalusia, Aragon, Castilla-Leon, Catalonia, Galicia, Canary Islands, Madrid Community, Valencian Community, Murcia Region and Basque Country) have been studied. Annual distribution of HCV genotypes and subtypes, as well as gender, age, transmission route, HIV and/or HBV coinfection, and treatment details were recorded. We included 48595 chronically HCV-infected patients with the following characteristics: median age 51 years (IQR, 44-58), 67.9% male, 19.1% HIV-coinfected, 23.5% HBV-coinfected. Parenteral transmission route was the most frequent (58.7%). Genotype distribution was 66.9% GT1 (24.9% subtype 1a and 37.9% subtype 1b), 2.8% GT2, 17.3% GT3, 11.4% GT4 and 0.1% GT5 and 0.02% GT6. LiPA was the most widely HCV genotyping test used (52.4%). HCV subtype 1a and genotypes 3 and 4 were closely associated with male gender, parenteral route of infection and HIV and HBV coinfection; in contrast, subtype 1b and genotype 2 were associated with female gender, nonparenteral route and mono-infection. Age was related to genotype distribution, and different patterns of distribution and biodiversity index were observed between different geographical areas. Finally, we describe how treatment and changes in transmission routes may have affected HCV genotype prevalence and distribution patterns. We present the most recent data on molecular epidemiology of hepatitis C virus in Spain. This study confirms that genotype distributions vary with age, sex, HIV and HBV coinfection and within geographical areas and epidemiological groups.

Drug resistance in patients experiencing early virological failure under a triple combination including indinavir.

OBJECTIVE: To assess the pattern of drug resistance mutations selected in HIV-1-infected patients failing a first line triple combination therapy including indinavir. PATIENTS AND METHODS: Plasma samples from 87 patients collected at the time of the first virological rebound (> 50 HIV-RNA copies/ml) were examined for the presence of drug-resistant genotypes. RESULTS: The mean level of plasma viraemia at rebound was 7824 HIV-1 RNA copies/ml in 73 subjects with good compliance, whereas it was 359,460 HIV-1 RNA copies/ml in 14 patients who admitted to poor adherence. Genetic sequence analysis yielded results for 51 (70%) of the patients having good adherence. More than half of them (26/51, 51%) carried primary mutations associated with resistance to nucleoside analogues. In contrast, primary protease inhibitor resistance mutations were recognized less frequently (14/51, 27%; P < 0.05). Moreover, in 23 (45%) patients there was no evidence of drug-resistant viruses at all. The most frequent drug-resistant genotypes in the reverse transcriptase gene were at codons 184 (n = 19), 215 (n = 14) and 41 (n = 8), whereas for the protease they were at codons 46 (n = 10), 82 (n = 9) and 90 (n = 7). No resistance genotypes were found among non-compliant patients. CONCLUSION: The overall rate of drug-resistant HIV genotypes was 38% (28/73) in patients with good adherence and who were experiencing a first virological failure under a triple combination regimen including indinavir; resistance to nucleoside analogues was more frequent than resistance to indinavir. Therefore, treatment intensification in those patients without resistance, or a selective substitution of nucleosides in those with resistance limited to these compounds, might be justified.

Phenotypic cross-resistance to nelfinavir: the role of prior antiretroviral therapy and the number of mutations in the protease gene.

Cross-resistance to nelfinavir (NFV) is observed in patients failing protease inhibitor (PI)-containing therapies. We performed a study with 111 patients who started an NFV-based salvage regimen after failing PI-based therapy to evaluate genotypic changes and to identify factors associated with resistance to NFV. Genotypic and phenotypic resistance data at entry (111 and 51 samples) and after NFV failure (74 and 31 samples) were available. Median CD4(+) cell count was 208 x 10(6)/liter, HIV RNA level was 4.6 log(10) copies/ml, and median number of mutations in the protease was 9. At baseline, 51 and 14% of viral isolates showed high or intermediate phenotypic resistance to NFV. Phenotypic data correlated with virological outcome, reaching undetectability at the third month in 40, 14, and 0% of those patients with susceptible, intermediate, or resistant viral isolates, respectively. Phenotypic resistance to NFV was associated with the presence of the L90M mutation: 46% for resistant vs. 6% in susceptible strains. The number of mutations in the protease correlated with the fold-increase in the IC(50)-NFV. The D30N mutation was detected in only 1 of 74 patients who failed. In a logistic regression analysis, the number of mutations in the protease was associated with NFV cross-resistance (RR, 2.09 per each additional mutation; 95% CI 1.23-3.55; p < 0.01). In conclusion, phenotypic cross-resistance to NFV for PI-experienced patients can be predicted by the number of mutations in the protease. The L90M mutation is significantly associated with the subsequent failure of NFV-containing regimens. The presence of the D30N mutation was rare and not useful in identifying NFV-resistant isolates.

Phenotypic testing predicts virological response in successive protease inhibitor-based regimens.

OBJECTIVE: To evaluate the importance of the number of active drugs, as determined by phenotypic resistance testing, in achieving virological response in successive salvage regimens. DESIGN: Phenotypic study of 57 plasma samples corresponding to 24 patients who had sequentially received three protease inhibitor-containing regimens. Phenotypic susceptibility to a drug (active drug) was defined as less than a four-fold-increase in the IC50 in comparison with the wild type. MAIN OUTCOME MEASURE: Virological response according to the number of active drugs (three versus two or fewer), HIV load, length of antiretroviral exposure, and line of protease inhibitor-based therapy (first, second and third regimen). RESULTS: Before the first protease inhibitor-based therapy, the median time on antiretroviral treatment was 42 months, and before the second and third protease inhibitor-salvage regimens it was 10 and 8 months, respectively. The number of patients receiving three active drugs simultaneously was 24, 35 and 31% in each line of therapy. At week 12, a close correlation was found between the presence of three active drugs in the antiretroviral regimen and the rate of virological response, in comparison with those patients receiving two or fewer active drugs [76 versus 45%, relative risk (RR), 1.7; 95% confidence interval (CI) 1.1-2.6; P = 0.028]. In a multivariate analysis, the use of two or fewer active drugs was an independent predictor of lack of response, regardless of HIV load, length of previous antiretroviral exposure and line of salvage therapy (RR, 4.5; 95%CI, 1.1-18.3; P = 0.03). Of note, a higher rate of response was observed in patients receiving the first protease inhibitor-containing regimen in comparison with those in subsequent protease inhibitor-based salvage regimens (83 versus 50 versus 28%, P < 0.01), even when only those patients receiving three active drugs were included (100 versus 71 versus 60%). CONCLUSIONS: This data confirm the usefulness of phenotypic testing in guiding antiretroviral therapy in heavily pretreated patients. The number of active drugs and the line of salvage therapy are independent predictors of virological response, regardless of HIV load and the length of antiretroviral exposure.

Non-nucleoside reverse transcriptase inhibitor resistance among patients failing a nevirapine plus protease inhibitor-containing regimen.

OBJECTIVE: To determine the rate of nevirapine resistance in patients failing a nevirapine plus protease inhibitor (PI)-based regimen, and whether these isolates remain susceptible to other non-nucleoside reverse transcriptase inhibitors (NNRTI). DESIGN AND SETTING: A retrospective cohort study in two tertiary university hospitals. PATIENTS: Eighty-eight HIV-infected, NNRTI-naive patients receiving nevirapine plus PI as a rescue regimen after PI treatment failure. MAIN OUTCOME MEASURES: Genotypic and phenotypic resistance data at inclusion (73 and 60 plasma samples, respectively) and after 24 weeks (53 and 42 samples). RESULTS: Baseline phenotypic susceptibility to nevirapine was found in 70% of patients, and similar data were observed for efavirenz (91%) and delavirdine (71%). NNRTI resistance-associated mutations were found in 11 patients (12.5%). At 24 weeks, resistant isolates to nevirapine were found in 92% of patients, and correlated with similar resistance to efavirenz (68%) and delavirdine (73%). In the genotypic analysis, the Y181 C mutation was observed in 76% of mutants, and the most common changes were a combination of mutations at positions Y181C/K103N (23%) and the single mutation Y181C (15%). The development of nevirapine resistance was associated with baseline resistance to PI included in the regimen (P= 0.01). For isolates containing the single amino acid substitution Y181C, 29% remained fully susceptible to efavirenz, whereas 14% showed intermediate resistance to efavirenz and delavirdine. CONCLUSION: The failure of a nevirapine plus PI-containing regimen is associated with nevirapine resistance in most patients, with the most common mutation occurring at amino acid residue 181. Although there is a high degree of cross-resistance among NNRTI, nearly one third of resistant isolates carrying the single Y181C mutation remain susceptible to efavirenz.

Re-treatment after Helicobacter pylori eradication failure.

AIM: Currently, highly effective Helicobacter pylori eradication therapies are used, and although eradication failures still appear in a considerable proportion of cases, the therapeutic efficacy in such refractory cases has been only exceptionally studied. Therefore, our aim was to evaluate the appropriate attitude when eradication therapy fails. METHODS: In 127 duodenal ulcer patients, several therapies with omeprazole (O) plus one or two antibiotics [amoxycillin (A), clarithromycin (C), metronidazole (M)] had failed to eradicate H. pylori. Re-treatment was administered depending on initial therapy; in no case was the same regimen repeated, and antibiotics with resistance risk (as C or M) were only re-administered using combination regimens with bismuth (B): O + A + C + B (when C was re-administered) and O + bismuth triple therapy (BTT) (when M was re-administered). RESULTS: First therapy and eradication rates, with the corresponding second therapy, were: CONCLUSION: BTT re-treatment in O + A failure achieves a relatively low eradication rate, probably lower than BTT for the first time, suggesting that other regimens should be tried. The following re-treatments are recommended in H. pylori eradication failure: in O + A failure, BTT (or O + BTT, as BTT re-treatment could be less effective than the initial BTT treatment); in O + C failure, O + A + M; in O + A + C failure, O + BTT; in O + A + M failure, O + A + C; and, finally, in O + C + M failure, O + BTT (or O + A + C + B).

[Omeprazole plus 2 antibiotics for the eradication of H. pylori, are 5 days of treatment sufficient?]. / Omeprazol más dos antibióticos para la erradicación de H. pylori, son suficientes cinco días de tratamiento?

OBJECTIVE: Combinations of omeprazole plus two antibiotics for seven days have repeatedly been studied and high Helicobacter pylori eradication rates have been obtained, ranging from 80% and 90% in our country. Our objective was to verify whether length of such therapies (with omeprazole, metronidazole and clarithromycin or amoxicillin) can be shortened to five days with no loss of efficacy. DESIGN: randomized clinical trial. PATIENTS: forty-eight consecutive patients with duodenal ulcer were prospectively studied. The exclusion criteria were previous administration of antibiotics, bismuth or gastroerosive drugs, and associated diseases. During the initial endoscopy biopsy specimens from antrum and corpus were obtained (haematoxylin-eosin). Two therapies were administered for five days: omeprazole (20 mg/12 h) and clarithromycin (500 mg/12 h) plus metronidazole (500 mg/12 h) (n = 24) or amoxicillin (1 g/12 h) (n = 24). One month after therapy was completed a new endoscopy was performed, biopsy specimens were obtained, and the 13C-urea breath test was performed. Compliance of therapy was assessed by questioning the patient and counting the residual medication. DATA ANALYSIS: multiple logistic regression and "intention-to-treat" analysis. OUTCOME VARIABLE: eradication was defined as the absence of H. pylori by all diagnostic methods. RESULTS: Mean age +/- SD was 48 +/- 10 years, 73% were males. Twenty-three patients in each group completed the protocol and the distribution of investigated parameters was similar in both groups. Eradication was obtained in 91.7% (95% CI = 74%-98%) in the metronidazole group and 70.8% (51%-85%) in the amoxicillin group (chi 2 = 2.19; p = 0.13). In the multivariate analysis, OR for the effect of type of therapy on eradication was 4.5 (CI = 0.83-24.7; p = 0.077). No relevant secondary effects were reported. The most common secondary effect was a metallic taste of medication, which was perceived by half of patients in each group. CONCLUSION: The combination of omeprazole, clarithromycin, and metronidazole for only five days has a high eradicating efficacy (approximately 90%), similar to that obtained in previous studies with seven days of therapy. Nevertheless, the association of omeprazole, clarithromycin, and amoxicillin should probably be administered at least for one week to reach an optimal eradicating efficacy.