Randomized trial of posaconazole and benznidazole for chronic Chagas' disease.

BACKGROUND: Current therapeutic options for Chagas' disease are limited to benznidazole and nifurtimox, which have been associated with low cure rates in the chronic stage of the disease and which have considerable toxicity. Posaconazole has shown trypanocidal activity in murine models. METHODS: We performed a prospective, randomized clinical trial to assess the efficacy and safety of posaconazole as compared with the efficacy and safety of benznidazole in adults with chronic Trypanosoma cruzi infection. We randomly assigned patients to receive posaconazole at a dose of 400 mg twice daily (high-dose posaconazole), posaconazole at a dose of 100 mg twice daily (low-dose posaconazole), or benznidazole at a dose of 150 mg twice daily; all the study drugs were administered for 60 days. We assessed antiparasitic activity by testing for the presence of T. cruzi DNA, using real-time polymerase-chain-reaction (rt-PCR) assays, during the treatment period and 10 months after the end of treatment. Posaconazole absorption was assessed on day 14. RESULTS: The intention-to-treat population included 78 patients. During the treatment period, all the patients tested negative for T. cruzi DNA on rt-PCR assay beyond day 14, except for 2 patients in the low-dose posaconazole group who tested positive on day 60. During the follow-up period, in the intention-to-treat analysis, 92% of the patients receiving low-dose posaconazole and 81% receiving high-dose posaconazole, as compared with 38% receiving benznidazole, tested positive for T. cruzi DNA on rt-PCR assay (P<0.01 for the comparison of the benznidazole group with either posaconazole group); in the per-protocol analysis, 90% of the patients receiving low-dose posaconazole and 80% of those receiving high-dose posaconazole, as compared with 6% receiving benznidazole, tested positive on rt-PCR assay (P<0.001 for the comparison of the benznidazole group with either posaconazole group). In the benznidazole group, treatment was discontinued in 5 patients because of severe cutaneous reactions; in the posaconazole groups, 4 patients had aminotransferase levels that were more than 3 times the upper limit of the normal range, but there were no discontinuations of treatment. CONCLUSIONS: Posaconazole showed antitrypanosomal activity in patients with chronic Chagas' disease. However, significantly more patients in the posaconazole groups than in the benznidazole group had treatment failure during follow-up. (Funded by the Ministry of Health, Spain; CHAGASAZOL ClinicalTrials.gov number, NCT01162967.).

Risk factors for respiratory failure in pneumococcal pneumonia: the importance of pneumococcal serotypes.

Pneumococcal serotypes are one of the main determinants of pneumococcal disease severity; however, data about their implication in respiratory failure are scarce. We conducted an observational study of adults hospitalised with invasive pneumococcal pneumonia to describe the host- and pathogen-related factors associated with respiratory failure. Of 1258 adults with invasive pneumococcal disease, 615 (48.9%) had respiratory failure at presentation. Patients with respiratory failure were older (62.1 years versus 55.4 years, p<0.001) and had a greater proportion of comorbid conditions. They also had a greater proportion of septic shock (41.7% versus 6.1%, p<0.001), required admission to the intensive care unit more often (38.4% versus 4.2%, p<0.001) and had a higher mortality (25.5% versus 3.5%, p<0.001). After adjustment, independent risk factors for respiratory failure were: age >50 years (OR 1.63, 95% CI 1.15-2.3), chronic lung disease (OR 1.54, 95% CI 1.1-2.15), chronic heart disease (OR 1.49, 95% CI 1.01-2.22) and infection caused by serotypes 3 (OR 1.97, 95% CI 1.23-3.16), 19A (OR 2.34, 95% CI 1.14-4.42) and 19F (OR 3.55, 95% CI 1.22-10.28). In conclusion, respiratory failure is a frequent complication of pneumococcal pneumonia and causes high morbidity and mortality. Pneumococcal serotypes 3, 19A and 19F are the main risk factors for this complication.

Liver biopsy-related infection in liver transplant recipients: A current matter of concern?

Data from published studies regarding risk factors for liver biopsy (LB)-related infectious complications in liver transplant recipients are inconsistent. We carried out a retrospective cohort study analyzing consecutive LBs for orthotopic liver transplant patients at a tertiary hospital (2001-2011): there were 667 LB procedures (575 percutaneous procedures and 92 transjugular procedures) in 286 liver transplant recipients. There were 20 complications in 19 patients (overall incidence = 3.0%): 10 were infectious complications (8 cases of bacteremia and 2 cases of peritonitis). The causal microorganisms were mainly Pseudomonas aeruginosa (4 patients) and Enterobacteriaceae (4 patients). All complications occurred with biopsies performed in patients hospitalized for more than 48 hours (381 biopsies for 201 patients); hence, only this group was included in the risk factor analysis. The variables associated with the development of infectious complications after LB were the presence of impaired biliary drainage at the time of biopsy (40% versus 15.1%, P = 0.03) and low albumin levels (2.4 versus 3.1 g/dL, P = 0.01). In conclusion, according to our experience, infectious complications secondary to LB in liver transplant recipients are related to hospitalization at the time of biopsy, particularly in the presence of impaired biliary drainage and low albumin levels.

Etiology and mortality of spontaneous bacterial peritonitis in liver transplant recipients: a cohort study.

Spontaneous bacterial peritonitis (SBP) in liver transplantation (LT) recipients who progress to cirrhosis has received little attention. We investigated the adequacy of empirical treatment with third-generation cephalosporins for SBP in this population and the impact of transplantation on the evolution of the infection. We performed a cohort study with 138 SBP episodes: 19 in LT patients and 119 in non-LT patients. The etiology of SBP was identified for 73.7% of the episodes in LT patients and for 38.7% of the episodes in non-LT patients (P = 0.004). The main microorganisms in recipients were Escherichia coli (35.7%) and Streptococcus pneumoniae (21.4%). The etiologies did not differ in non-LT patients. The cephalosporin sensitivity was similar in the 2 groups (85.7% versus 78.4%, P = 0.7). LT recipients developed renal failure (57.9% versus 25.2%, P = 0.004) and encephalopathy (42.1% versus 22%, P = 0.08) more often than non-LT patients, and the mortality rates during episodes (52.6% versus 13.4%, P < 0.001) and at 6 months (70.6% versus 34.7%, P = 0.005) were higher. According to a multivariate analysis, the mortality-associated risk factors at diagnosis were a Model for End-Stage Liver Disease (MELD) score > 18 odds ratio (OR) = 6.1 and being an LT recipient (OR = 4.45). At 6 months, the risk factors for mortality were a MELD score > 18 (OR = 3.08), being an LT recipient (OR = 3.47), a known etiology (OR = 2.08), and the presence of hepatocellular carcinoma (OR = 3.73).

Ampicillin plus ceftriaxone is as effective as ampicillin plus gentamicin for treating enterococcus faecalis infective endocarditis.

BACKGROUND: The aim of this study was to compare the effectiveness of the ampicillin plus ceftriaxone (AC) and ampicillin plus gentamicin (AG) combinations for treating Enterococcus faecalis infective endocarditis (EFIE). METHODS: An observational, nonrandomized, comparative multicenter cohort study was conducted at 17 Spanish and 1 Italian hospitals. Consecutive adult patients diagnosed of EFIE were included. Outcome measurements were death during treatment and at 3 months of follow-up, adverse events requiring treatment withdrawal, treatment failure requiring a change of antimicrobials, and relapse. RESULTS: A larger percentage of AC-treated patients (n = 159) had previous chronic renal failure than AG-treated patients (n = 87) (33% vs 16%, P = .004), and AC patients had a higher incidence of cancer (18% vs 7%, P = .015), transplantation (6% vs 0%, P = .040), and healthcare-acquired infection (59% vs 40%, P = .006). Between AC and AG-treated EFIE patients, there were no differences in mortality while on antimicrobial treatment (22% vs 21%, P = .81) or at 3-month follow-up (8% vs 7%, P = .72), in treatment failure requiring a change in antimicrobials (1% vs 2%, P = .54), or in relapses (3% vs 4%, P = .67). However, interruption of antibiotic treatment due to adverse events was much more frequent in AG-treated patients than in those receiving AC (25% vs 1%, P < .001), mainly due to new renal failure (≥25% increase in baseline creatinine concentration; 23% vs 0%, P < .001). CONCLUSIONS: AC appears as effective as AG for treating EFIE patients and can be used with virtually no risk of renal failure and regardless of the high-level aminoglycoside resistance status of E. faecalis.

Epidemiology of Clostridium difficile infection and risk factors for unfavorable clinical outcomes: results of a hospital-based study in Barcelona, Spain.

Prospective hospital-based surveillance for Clostridium difficile-associated disease (CDAD) was conducted in Barcelona (Spain) to describe the epidemiology of this condition and investigate the risk factors for an unfavorable outcome. All patients diagnosed with CDAD during 2009 were included. Using logistic regression modeling, we analyzed the potential risk factors associated with recurrent and complicated CDAD, defined as a need for colectomy or death within 30 days. There were 365 episodes of CDAD, yielding an incidence of 22.5 cases/10(5) person-years, 1.22 cases/10(3) hospital discharges, and 1.93 cases/10(4) patient-days. The main PCR ribotypes identified were 241 (26%), 126 (18%), 078 (7%), and 020 (5%). PCR ribotype 027 was not detected. Among the 348 cases analyzed, 232 (67%) patients were cured, 63 (18%) had a recurrence of CDAD, and 53 (15%) developed complicated CDAD. Predictors of complicated CDAD were continued use of antibiotics following CDAD diagnosis (odds ratio [OR], 2.009; 95% confidence interval [CI], 1.012 to 3.988; P = 0.046), Charlson comorbidity index score (OR, 1.265; 95% CI, 1.105 to 1.449; P = 0.001), and age (OR, 1.028; 95% CI, 1.005 to 1.053; P = 0.019). A leukocyte count of >15 × 10(3) cells/ml (OR, 2.277; 95% CI, 1.189 to 4.362; P = 0.013), continuation of proton pump inhibitor (PPI) use after CDAD diagnosis (OR, 2.168; 95% CI, 1.081 to 4.347; P = 0.029), and age (OR, 1.021; 95% CI, 1.001 to 1.041; P = 0.036) were independently associated with higher odds of recurrence. The incidence of CDAD in Barcelona during 2009 was on the lower end of the previously described range for all of Europe. Our analysis suggests that the continuation of non-C. difficile antibiotics and use of PPIs in patients diagnosed with CDAD are associated with unfavorable clinical outcomes.

The increasing incidence of empyema.

PURPOSE OF REVIEW: The aim of this review is to highlight recent changes concerning the incidence of empyema. In this article we have focused on community-acquired empyema RECENT FINDINGS: The incidence of empyema seems to have been increasing both in children and adults worldwide in the past decades, mainly in healthy young adults and in older patients. The bacteriology of pleural infection is changing as well. In children, the most common microorganism that causes empyema continues to be Streptococcus pneumoniae. Interestingly, the widespread use of the seven valent conjugate vaccine has produced a replacement phenomenon with the emergence of some pneumococcal serotypes such as serotypes 1, 3 and 19A, which have a higher propensity to cause empyema. Moreover increases in the incidence of empyema due to Staphylococcus aureus have also been observed. In adults, increases in the rate of empyema due to Streptococcus milleri group and S. aureus have been reported. SUMMARY: Continued surveillance in the epidemiology of empyema is needed. Progress in new strategies of prevention, such as a new generation of conjugate pneumococcal vaccines and protein-based vaccines, could become an important step in the control of this important complication.

Simplification to dual antiretroviral therapy including a ritonavir-boosted protease inhibitor in treatment-experienced HIV-1-infected patients.

OBJECTIVES: To assess the effectiveness of simplification to a dual antiretroviral regimen containing a ritonavir-boosted protease inhibitor (PI/r) in treatment-experienced HIV-1-infected patients. METHODS: Retrospective analysis of 131 HIV-1-infected patients on suppressive antiretroviral treatment (HIV-RNA <50 copies/mL) who switched to a maintenance dual antiretroviral regimen, containing a PI/r, in three hospitals in Spain. Virological failure was defined as confirmed HIV-RNA >50 copies/mL. The percentage of patients remaining free of therapeutic failure was estimated using the time-to-loss-of-therapeutic-response algorithm, by intent-to-treat analysis. RESULTS: Median baseline characteristics of the patients were 14 years on antiretroviral therapy, five prior HAART regimens and 10 different drugs, 24 months on a suppressive regimen and 522 CD4+ cells/mL. Reasons for simplification to dual therapy were nucleoside reverse transcriptase inhibitor-related toxicity (46.6%), removal of lamivudine/emtricitabine due to resistance (16.8%), simplification from regimens containing a dual PI, enfuvirtide or tipranavir (20.6%) and simplification from other complex regimens (16.0%). Darunavir (58.0%), lopinavir (16.8%) or atazanavir (13.0%) were the preferred PIs, used in combination with tenofovir (50.4%), raltegravir (22.1%) or etravirine (12.2%). At the end of follow-up (median 14 months), 90.1% of patients remained free of therapeutic failure; corresponding data at treatment weeks 24, 48 and 96 were 93.6% (95% CI, 89.3-97.9), 90.9% (95% CI, 84.9-95.9) and 87.4% (95% CI, 80.7-94.1), respectively. Two (1.5%) patients had virological failure and 11 (8.4%) discontinued treatment due to side effects or were lost to follow-up. CONCLUSIONS: Simplification to a dual-therapy regimen including a PI/r might be useful to enhance convenience and/or diminish toxicity in selected treatment-experienced patients.

Outcome of Clostridium difficile-associated disease in solid organ transplant recipients: a prospective and multicentre cohort study.

Clostridium difficile-associated disease (CDAD) is the most common cause of nosocomial diarrhea. Information about CDAD in solid organ transplant (SOT) recipients is scarce. To determine its epidemiology and risk factors, we conducted a cohort study in which 4472 SOT patients were prospectively included in the RESITRA/REIPI (Spanish Research Network for the Study of Infection in Transplantation) database between July 2003 and July 2006. Forty-two episodes of CDAD were diagnosed in 36 patients. The overall incidence was 0.94%. Median onset of infection was 31.5 days (range 6-741); in half the cases, onset occurred during the first month after transplantation. In 26% of cases, there was no previous antibiotic use. Independent risk factors for CDAD using Cox regression analysis were previous use of first- and second-generation cephalosporins (HR 3.68; 95%CI 1.8-7.52; P < 0.001), ganciclovir prophylactic use (HR 3.09; 95%CI 1.44-6.62; P = 0.004) and corticosteroid use before transplantation (HR 2.95; 95%CI 1.1-7.9; P = 0.031). There were no deaths related to CDAD. In summary, the incidence of CDAD in SOT was low, most cases were diagnosed soon after transplantation and the prognosis was good.

[Invasive fungal infection in solid organ transplant]. / Infección fúngica invasora en el trasplante de órgano sólido.

Invasive fungal infections (IFI) represent a serious threat for patients undergoing solid organ transplantation (SOT). IFI in SOT has a significant incidence and mortality not due to negligence. The management of IFI in SOT involves specific recommendations and has been individualized to the type of transplant and patient. The current review presents an overview of epidemiology, diagnosis, treatment and prevention of IFI in TOS. Depending on risk factors for different IFIs and transplant type, this paper includes the main recommendations based on previous publications and on the opinion of the authors on the prophylaxis and treatment of these patients. These recommendations highlight epidemiology changes and the emergence of new antifungals. The current document has focused mainly on Candidaspp. and Aspergillusspp., with a special mention to the rest of yeasts and moulds that are common in SOT.

Evaluating the risk of transmission of infection from donor to recipient of a solid organ transplantation.

In the context of solid organ transplantation, screening of potential organ donors is crucial, and should be performed with great rigor to minimize the risk of transmission of certain infectious processes. This review aims to update understanding of the possible pathologies involved, as well as of emerging infections that, as a result of globalization, are gaining increasing prominence on a daily basis.

The spectrum of pneumococcal empyema in adults in the early 21st century.

BACKGROUND: Increased rates of empyema have been reported in children after the introduction of the pneumococcal conjugate vaccine (PCV7). Our objective was to describe the risk factors for pneumococcal empyema in adults and to analyze the differences in the incidence, disease characteristics, and serotype distribution between the pre- and post-PCV7 eras. METHODS: An observational study of all adults hospitalized with invasive pneumococcal disease (IPD) who presented with empyema in 2 Spanish hospitals was conducted during the periods 1996-2001 (prevaccine period) and 2005-2009 (postvaccine period). Incidences of empyema were calculated. A multivariate analysis was performed to identify variables associated with pneumococcal empyema. RESULTS: Empyema was diagnosed in 128 of 1080 patients with invasive pneumococcal disease. Among patients aged 18-50 years, the rates of pneumococcal pneumonia with empyema increased from 7.6% to 14.9% (P = .04) and the incidence of pneumococcal empyema increased from 0.5 to 1.6 cases per 100,000 person-years (198% [95% confidence interval {CI}, 49%-494%]). The incidence of empyema due to serotype 1 increased significantly from 0.2 to 0.8 cases per 100,000 person-years (253% [95% CI, 67%-646%]). Serotype 1 caused 43.3% of cases of empyema during the postvaccine period. Serotypes 1 (odds ratio [OR], 5.88; [95% CI, 2.66-13]) and 3 (OR, 5.49 [95% CI, 1.93-15.62]) were independently associated with development of empyema. CONCLUSIONS: The incidence of pneumococcal empyema in young adults has increased during the postvaccine period, mainly as a result of the emergence of serotype 1. Serotypes 1 and 3 are the main determinants of development of this suppurative complication.

Effectiveness of antibiotic-lock therapy for long-term catheter-related bacteremia due to Gram-negative bacilli: a prospective observational study.

A prospective observational study evaluated the effectiveness of combining antibiotic-lock therapy and systemic antibiotics for Gram-negative bacilli long-term catheter-related bacteremia. In 46 uncomplicated episodes, the most frequently isolated microorganisms were Pseudomonas aeruginosa (15), Enterobacter cloacae (12), Escherichia coli (10), and Klebsiella spp. (8). Cure was achieved in 95% of cases.

Safety of liver transplantation with Chagas disease-seropositive donors for seronegative recipients.

The shortage of organs for transplantation has prompted the investigation of extended criteria donors, such as donors with transmissible infectious diseases. Here we report our recent experience with liver transplantation using organs from donors who were serologically positive for Chagas disease. We also provide a review of the literature and emphasize donor screening and preventive measures.

Emerging drugs for pneumococcal pneumonia.

INTRODUCTION: Nowadays, despite excellent antibiotics being available, mortality of pneumococcal pneumonia remains high. The excellent antipneumococcal activity and the large amount of clinical data available with ß-lactams and fluorquinolones will probably delay the need for new antibiotics. However, concerns about the evolution of antibiotic resistance justify the review of new indications for known antibiotics and the development of new products. AREAS COVERED: In this review, the authors focus on the actual situation of pneumococcal antibiotic resistance, the different antimicrobial therapies available and future therapeutic options as well as novel therapeutic strategies. An extensive literature review of manuscripts published in the last 10 years has been performed. This is a review of all antimicrobials for the treatment of pneumococcal pneumonia. Both actual antibiotics available and new antibiotics that may have a role in the treatment of pneumococcal pneumonia are extensively reviewed. The utility of combination therapy with ß-lactams and macrolides is discussed. EXPERT OPINION: ß-Lactams continue to be the drugs of choice for pneumococcal pneumonia. Fluorquinolones constitute an excellent alternative therapy. Patients with shock or severe sepsis should probably receive combination therapy with ß-lactams plus a macrolide due to its immunomodulatory effect.

[Lights and shadows of cytomegalovirus infection in solid organ transplantation]. / Luces y sombras de la infección por citomegalovirus en el trasplante de órgano sólido.

Cytomegalovirus (CMV) develops in 30-80% of patients undergoing solid organ transplantation (SOT). The incidence and presence of symptomatic disease varies depending on the type of transplant, the presence of associated risk factors, the intensity of immunosuppression, and the prevention strategies used. The impact of CMV on SOT is due not only to the effects of CMV disease per se, but also to its multiple indirect effects resulting from its immunomodulatory role and immunoactivation caused by viral latency. The two prophylactic strategies used (universal prophylaxis and preemptive therapy) are equally useful. Both strategies have advantages and disadvantages, and uncertainties remain on the populations that should receive prophylaxis and for how long. Viral monitoring to detect CMV infection is important for diagnosis, prognosis and evaluation of treatment response. The new real-time polymerase chain reaction techniques have provided numerous advantages but standardization remains an issue and common reference values are required. Specific anti-CMV drugs are available but issues such as the role of valganciclovir versus ganciclovir, the development of resistances and optimal treatment length are still being debated. Complementary therapy with mTOR inhibitors and vaccine strategies against CMV are alternatives for which conclusive data are lacking.

GESITRA-SEIMC/REIPI recommendations for the management of cytomegalovirus infection in solid-organ transplant patients.

Cytomegalovirus infection remains a major complication of solid organ transplantation. In 2005 the Spanish Transplantation Infection Study Group (GESITRA) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) developed consensus guidelines for the prevention and treatment of CMV infection in solid organ transplant recipients. Since then, numerous publications have clarified or questioned the aspects covered in the previous document. These aspects include the situations and populations who must receive prophylaxis and its duration, the selection of the best diagnosis and monitoring technique and the best therapeutic strategy. For these reasons, we have developed new consensus guidelines to include the latest recommendations on post-transplant CMV management based on new evidence available.

Evaluation of linezolid, vancomycin, gentamicin and ciprofloxacin in a rabbit model of antibiotic-lock technique for Staphylococcus aureus catheter-related infection.

BACKGROUND: The effectiveness of linezolid, vancomycin, ciprofloxacin and gentamicin for treating experimental Staphylococcus aureus catheter-related infection by the antibiotic-lock technique was assessed. METHODS: Two methicillin-susceptible (MSSA) ATCC strains and two methicillin-resistant (MRSA) clinical strains were used. New Zealand white rabbits were surgically implanted with a silicone intravenous catheter. Infection was induced by filling and locking the catheter with 0.3 mL of broth culture containing S. aureus, with turbidity equivalent to that of a 0.5 McFarland standard. Eighteen hours later the antibiotic-lock technique was started and continued for 24 h. Treatment groups were: control without treatment; 2000 mg/L linezolid; 2000 mg/L vancomycin; 2000 mg/L ciprofloxacin; and 40,000 mg/L gentamicin. RESULTS: Linezolid and vancomycin showed equivalent activity, achieving significant reductions in log(10) cfu recovered from catheter tips in one MSSA strain (>1.12) and one MRSA strain (>0.77) as compared with controls (P < 0.05). Ciprofloxacin achieved significant log(10) cfu reductions in MSSA strains relative to controls (>2.51, P < 0.01). In one MSSA strain, ciprofloxacin showed a larger reduction in log(10) cfu than linezolid or vancomycin (P < 0.01). Gentamicin was the only antibiotic achieving negative catheter tip cultures (up to 87.5% in MSSA and up to 40% in MRSA, P < 0.01), and showed the greatest log(10) cfu reduction compared with controls (>4.25 in MSSA and >2.93 in MRSA, P < 0.05) and significant differences relative to the remaining treatment groups (P < 0.05 in both MSSA and MRSA). CONCLUSIONS: Gentamicin showed the highest activity against both MSSA and MRSA biofilms.

Response-guided therapy for chronic hepatitis C virus infection in patients coinfected with HIV: a pilot trial.

BACKGROUND: To study the feasibility of a response-guided therapy for chronic hepatitis C virus (HCV) infection in patients coinfected with human immunodeficiency virus (HIV) in a tertiary care hospital. METHODS: Treatment duration was individualized on the basis of week 4 and week 12 virologic response. Sixty patients were enrolled and received pegylated interferon alfa-2b (1.5 microg/kg per week) plus weight-based ribavirin (800-1400 mg/day). Patients who achieved a rapid virologic response, defined as viral load <50 IU/mL at treatment week 4, completed 24 weeks of therapy. Patients who did not achieve a rapid virologic response were reassessed at treatment week 12. Patients with a complete early virologic response, defined as an HCV RNA level <600 IU/mL, were treated for 48 weeks. Patients with a partial response, defined as a decrease in the viral load > or = 2 log10 and an HCV RNA level > or = 600 IU/mL, who attained an undetectable viral load at week 24 were treated for 60 weeks. The primary efficacy end point was sustained virologic response, defined as HCV RNA <50 IU/mL, 24 weeks after the end of treatment. RESULTS: Overall, 33 (55%) of 60 patients achieved a sustained virologic response: 11 (44%) of 25 patients with HCV genotype 1, 3 (27%) of 11 patients with genotype 4, and 19 (79%) of 24 patients with genotype 3. One-third of patients showed a rapid virologic response. Of patients with genotype 1, there was a rapid virologic response in 4 (16%) of 25; with genotype 4, in 1 (9%) of 11; and with genotype 3, in 14 (58%) of 24. Of the 19 patients with a rapid virologic response, 17 (89.5%) eradicated the virus after 24 weeks of therapy. The rate of sustained virologic response was significantly higher among patients with genotype 3 and low pretreatment HCV RNA levels. A high relapse rate (46%) after 48 weeks of therapy occurred among patients infected with genotypes 1 or 4 who first achieved undetectable viral load at treatment week 12. CONCLUSION: A response-guide therapy is feasible and may be useful to optimize the individual outcome of HCV treatment in patients coinfected with HIV.

Data mining validation of fluconazole breakpoints established by the European Committee on Antimicrobial Susceptibility Testing.

European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints classify Candida strains with a fluconazole MIC < or = 2 mg/liter as susceptible, those with a fluconazole MIC of 4 mg/liter as representing intermediate susceptibility, and those with a fluconazole MIC > 4 mg/liter as resistant. Machine learning models are supported by complex statistical analyses assessing whether the results have statistical relevance. The aim of this work was to use supervised classification algorithms to analyze the clinical data used to produce EUCAST fluconazole breakpoints. Five supervised classifiers (J48, Correlation and Regression Trees [CART], OneR, Naïve Bayes, and Simple Logistic) were used to analyze two cohorts of patients with oropharyngeal candidosis and candidemia. The target variable was the outcome of the infections, and the predictor variables consisted of values for the MIC or the proportion between the dose administered and the MIC of the isolate (dose/MIC). Statistical power was assessed by determining values for sensitivity and specificity, the false-positive rate, the area under the receiver operating characteristic (ROC) curve, and the Matthews correlation coefficient (MCC). CART obtained the best statistical power for a MIC > 4 mg/liter for detecting failures (sensitivity, 87%; false-positive rate, 8%; area under the ROC curve, 0.89; MCC index, 0.80). For dose/MIC determinations, the target was >75, with a sensitivity of 91%, a false-positive rate of 10%, an area under the ROC curve of 0.90, and an MCC index of 0.80. Other classifiers gave similar breakpoints with lower statistical power. EUCAST fluconazole breakpoints have been validated by means of machine learning methods. These computer tools must be incorporated in the process for developing breakpoints to avoid researcher bias, thus enhancing the statistical power of the model.