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After allogeneic hematopoietic stem cell transplantation (HSCT), BK virus–associated hemorrhagic cystitis (BKV-HC) is a common complication. Although supportive measures have been the standard of care for many years, several studies suggested the efficacy of cidofovir. The aim of this study was to assess the safety profile and efficacy of cidofovir. A retrospective study was conducted on all patients treated with cidofovir in our HSCT unit between March 2011 and May 2013. Data for efficacy (partial [PR] or complete response [CR]), prescription (dose, frequency, number of doses, and administration route), and toxicity were collected from published reports and medical files. Renal toxicity was evaluated using creatinine clearance calculated with the Cockcroft and Gault formula. A parallel literature search using PubMed (last search, May 2015) was performed. From March 2011 to June 2013, 27 of 181 patients undergoing allogeneic HSCT in our department received cidofovir for BKV-HC: 24 (88.9%) intravenously, 1 intravesically, and 2 via both routes. Mean dose was 5 mg/kg per administration, for a median of 4 injections (range, 1 to 11), from twice a week to once every 2 weeks. CR was achieved in 22 patients (81.5%), PR in 2, and no response in 2 patients. Eight patients presented renal failure (29.6%): 6 moderate (creatinine clearance < 60 mL/min) and 2 severe (creatinine clearance < 30 mLmin). Mean decrease in creatinine clearance after cidofovir was 27% (35 mL/min; range, 2 to 159). In 3 cases renal insufficiency and hematologic toxicity led to discontinuation of treatment or switch to intravesical instillation. For 3 patients cidofovir dose was reduced because of nephrotoxicity. Thirteen studies have reported on the use of cidofovir for BKV-HC (204 patients) since 2005. Intravenous cidofovir was used for 91.3% of patients, with doses ranging from .5 to 5 mg/kg. The main toxicity reported was renal failure (9% to 50% in 9 studies). Between 60% and 100% of CRs were observed independently of cidofovir dose or administration route. Cidofovir is an effective therapy for BKV-HC but requires very precise renal function management to avoid toxicity. Cidofovir treatment modalities (high dose, intravesical instillation, or low dose [≤1 mg/kg]) needs to be investigated in randomized controlled trials. [ABSTRACT FROM AUTHOR]

Background: Even if daptomycin does not have approval for the treatment of bone and joint infections (BJI), the Infectious Diseases Society of America guidelines propose this antibiotic as alternative therapy for prosthetic joint infection. The recommended dose is 6 mg/kg/d, whereas recent data support the use of higher doses in these patients.Methods: We performed a cohort study including consecutive patients that have received daptomycin >6 mg/kg/d for complex BJI between 2011 and 2013 in a French regional reference center. Factors associated with treatment failure were determined on univariate Cox analysis and Kaplan-Meier curves.Results: Forty-three patients (age, 61 ± 17 years) received a mean dose of 8 ± 0.9 mg/kg/d daptomycin, for a mean 81 ± 59 days (range, 6-303 days). Most had chronic (n = 37, 86 %) implant-associated (n = 37, 86 %) BJI caused by coagulase-negative staphylococci (n = 32, 74 %). A severe adverse event (SAE) occurred in 6 patients (14 %), including 2 cases of eosinophilic pneumonia, concomitant with daptomycin Cmin >24 mg/L. Outcome was favorable in 30 (77 %) of the 39 clinically assessable patients. Predictors for treatment failure were age, non-optimal surgery and daptomycin withdrawal for SAE.Conclusions: Prolonged high-dose daptomycin therapy was effective in patients with complex BJI. However, optimal surgery remains the cornerstone of medico-surgical strategy; and a higher incidence of eosinophilic pneumonia than expected was recorded. [ABSTRACT FROM AUTHOR]

Linezolid (LNZ), a group 5 antituberculous drug (unclear efficacy), was used in the starter regimens of 23 adults with multidrug-resistant tuberculosis. The LNZ-containing regimens were effective in achieving culture conversions and relapse-free outcomes. The most frequent LNZ-related side effect was neuropathy. We propose that LNZ should be reclassified among bactericidal second-line drugs. [ABSTRACT FROM AUTHOR]

A 35-year-old woman with severe cystic fibrosis was admitted for sudden loss of strength in both legs, revealing a myelitis. The medullary lesion biopsy revealed phaeohyphomycosis caused by Cladophialophora species. Myelitis caused by Cladophialophora bantiana is a rare disease associated with high mortality. [ABSTRACT FROM AUTHOR]

The widespread use of acyclovir (ACV) and the increasing number of immunocompromised patients have raised concern about an increase in ACV-resistant herpes simplex virus (HSV). ACV resistance has traditionally been a major concern for immunocompromised patients with a frequency reported between 2.5% and 10%. The aim of this study was to reassess the status of HSV resistance to ACV in immunocompetent and immunocompromised patients over a ten year period, between 2002 and 2011. This was done by retrospectively following 1425 patients. In immunocompetent patients, prevalence of resistance did not exceed 0.5% during the study period; whereas in immunocompromised patients, a significant increase was observed, rising from 3.8% between 2002 and 2006 (7/182 patients) to 15.7% between 2007 and 2011 (28/178) ( p = 0.0001). This sharp rise in resistance may largely be represented by allogeneic hematopoietic stem cell transplant patients, in which the prevalence of ACV resistance rose similarly from 14.3% (4/28) between 2002 and 2006 to 46.5% (26/56) between 2007 and 2011 ( p = 0.005). No increase in ACV resistance was detected in association with other types of immune deficiencies. Genotypic characterization of HSV UL23 thymidine kinase and UL30 DNA polymerase genes revealed 11 and 7 previously unreported substitutions, respectively. These substitutions may be related to potential polymorphisms, drug resistance, or other mutations of unclear significance. [ABSTRACT FROM AUTHOR]

Background Several vaccines are recommended in HIV-infected patients due to an increased risk of vaccine-preventable infections, severe forms of the disease, or shared transmission routes. Few data are available regarding vaccination coverage and its determinants in this population. Methods A cross-sectional study was performed in HIV-infected patients included in a hospital-based cohort in 2011. Vaccination coverage against hepatitis A virus (HAV), hepatitis B virus (HBV), seasonal and A(H1N1)2009 pandemic influenza, and invasive pneumococcal diseases (IPD) were recorded. Factors associated with vaccination were assessed by multivariate logistic regression. Results 2467 patients were included (median age 47 years; male gender 71.5%; men having sex with men (MSM) 43.9%; CDC stage C 24.3%; HBV and/or hepatitis C virus co-infection 14.4%). Median duration of HIV infection was 10 years and 93.1% of patients received combination antiretroviral therapy. At baseline, the median CD4 count was 527 cells/mm³ and HIV viral load was <50 copies/mL in 83.3% of cases. Vaccination coverage for HBV, HAV, seasonal influenza, A(H1N1)2009 pandemic influenza, and IPD were 61.9%, 47.4%, 30.9, 48.3%, and 64.6%, respectively. Factors independently associated with vaccination were a younger (HBV) or an older age (influenza), male gender (HBV, HAV), MSM (HBV), CD4 count >200/mm³ and HIV-RNA <50 copies/mL (IPD, influenza), longer duration of HIV infection (IPD, influenza), and follow-up by an experienced physician (HBV, IPD). Conclusions Vaccination coverage remained insufficient for all vaccine-preventable infections investigated in this study. Determinants for vaccination were largely not evidence-based, and efforts should be focused on improving physicians' knowledge about guidelines. [ABSTRACT FROM AUTHOR]

Background: Although methicillin-susceptible Staphylococcus aureus (MSSA) native bone and joint infection (BJI) constitutes the more frequent clinical entity of BJI, prognostic studies mostly focused on methicillin-resistant S. aureus prosthetic joint infection. We aimed to assess the determinants of native MSSA BJI outcomes. Methods: Retrospective cohort study (2001–2011) of patients admitted in a reference hospital centre for native MSSA BJI. Treatment failure determinants were assessed using Kaplan-Meier curves and binary logistic regression. Results: Sixty-six patients (42 males [63.6%]; median age 61.2 years; interquartile range [IQR] 45.9–71.9) presented an acute (n = 38; 57.6%) or chronic (n = 28; 42.4%) native MSSA arthritis (n = 15; 22.7%), osteomyelitis (n = 19; 28.8%) or spondylodiscitis (n = 32; 48.5%), considered as “difficult-to-treat” in 61 cases (92.4%). All received a prolonged (27.1 weeks; IQR, 16.9–36.1) combined antimicrobial therapy, after surgical management in 37 cases (56.1%). Sixteen treatment failures (24.2%) were observed during a median follow-up period of 63.3 weeks (IQR, 44.7–103.1), including 13 persisting infections, 1 relapse after treatment disruption, and 2 super-infections. Independent determinants of treatment failure were the existence of a sinus tract (odds ratio [OR], 5.300; 95% confidence interval [CI], 1.166–24.103) and a prolonged delay to infectious disease specialist referral (OR, 1.134; 95% CI 1.013–1.271). Conclusions: The important treatment failure rate pinpointed the difficulty of cure encountered in complicated native MSSA BJI. An early infectious disease specialist referral is essential, especially in debilitated patients or in presence of sinus tract. [ABSTRACT FROM AUTHOR]

The aim of the present study was to detect the Staphylococcus aureus delta-toxin using Whole-Cell (WC) Matrix Assisted Laser Desorption Ionization - Time-of-Flight (MALDI-TOF) mass spectrometry (MS), correlate delta-toxin expression with accessory gene regulator (agr) status, and assess the prevalence of agr deficiency in clinical isolates with and without resistance to methicillin and glycopeptides. The position of the delta-toxin peak in the mass spectrum was identified using purified delta-toxin and isogenic wild type and mutant strains for agr-rnaIII, which encodes delta-toxin. Correlation between delta-toxin production and agr RNAIII expression was assessed by northern blotting. A series of 168 consecutive clinical isolates and 23 unrelated glycopeptide-intermediate S. aureus strains (GISA/heterogeneous GISA) were then tested by WCMALDI- TOF MS. The delta-toxin peak was detected at 3005±5 Thomson, as expected for the naturally formylated delta toxin, or at 3035±5 Thomson for its G10S variant. Multivariate analysis showed that chronicity of S. aureus infection and glycopeptide resistance were significantly associated with delta-toxin deficiency (p = 0.048; CI 95%: 1.01-10.24; p = 0.023; CI 95%: 1.20-12.76, respectively). In conclusion, the S. aureus delta-toxin was identified in the WC-MALDI-TOF MS spectrum generated during routine identification procedures. Consequently, agr status can potentially predict infectious complications and rationalise application of novel virulence factor-based therapies. [ABSTRACT FROM AUTHOR]

The article analyzes the virulence of 56 nonclonal Pseudomonas aeruginosa strains taken from patients with ventilator-acquired pneumonia in an effort to determine which among these factors is the most important. The authors report that they used a murine model of pneumonia to avoid human immune response variation. They reveal that their experiment showed that type three secretion system and elastase are the most important virulence factors among strains of Pseudomonas aeruginosa.

The article discusses the case of a 50-year-old woman who was diagnosed with nontuberculous mycobacteria (NTM) infection and treated due to the detection of the interferon-y (IFN-y) autoantibodies. Topics discussed include her pathological examination that revealed a nonnecrotizing granuloma, the continued use of the antimycobacterial treatment and changed to azithromycin suppressive therapy and a reviewed literature for the other cases of IFN-y antibody-related NTM infection.

Abstract: Microbial adherence to host cells is an early key step in the establishment of infection. During the course of Legionnaire''s disease, Legionella interactions with host cells are best documented for resident macrophages. However, L. pneumophila can also replicate within type I and type II pneumocytes, which cover almost the entire alveolar surface. In the presence of zinc, we observed a significant and concentration-dependent increase in L. pneumophila adherence to and invasion of type II pneumocytes. The zinc-dependent adherence mechanism seemed to be host-cell-independent, as a similar increase in cytoadherence was observed with macrophages. We also found that zinc-dependent adherence of L. pneumophila appears to involve recognition of zinc-binding pneumocyte receptors by a bacterial adhesin, and heparan-sulfated host cell receptors, but not type IV pili. [Copyright &y& Elsevier]

Objective: Pseudomonas aeruginosa-induced lung injury is characterized not only by the alteration in lung fluid movement but also by apoptosis of lung epithelial and endothelial cells. We studied whether inhibition of apoptosis using a broad spectrum caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp fluoromethylketone (Z-VAD.fmk), would affect lung fluid balance in rat P. aeruginosa pneumonia.Methods: Z-VAD.fmk (3 mg/kg) was administered intravenously simultaneously with P. aeruginosa intratracheal instillation (0.5 ml/kg, 2 x 10(9) CFU/ml). Apoptosis was evaluated with the TUNEL technique, cytoplasmic oligonucleosome assay, and caspase 3 activation. To evaluate lung permeability, extravascular plasma equivalent (EPE) and lung wet to dry weight ratio (W/D) were measured 4 h after intratracheal instillation of P. aeruginosa.Results: We found an increase of lung apoptosis 4 h after P. aeruginosa instillation: cytoplasmic oligonucleosome assay increased from 3.17+/-0.78 to 26.82+/-4.67 ODx1000/mg of proteins/ml, Z-VAD.fmk administration decreased this parameter to 10.3+/-2.98 ODx1000/mg of proteins/ml. Caspase 3 levels followed the same pattern. Apoptosis involved both epithelial cells and endothelial cells. Endothelial permeability was increased after Pseudomonas instillation: W/D increased from 3.75+/-0.28 in the Co group to 4.42+/-0.23 in the Pn group; EPE was also higher in the Pn group compared with the Co group (0.125+/-0.04 and 0.002+/-0.01 ml, respectively). Both of these parameters were improved after Z-VAD.fmk administration; W/D decreased to 3.36+/-0.25 and EPE to 0.02+/-0.02 ml.Conclusion: Apoptosis occurs in the early phase of P. aeruginosa pneumonia. Administration of Z-VAD.fmk significantly decreases DNA fragmentation and caspase 3 levels. This is associated with an improvement of endothelial permeability and lung fluid balance. [ABSTRACT FROM AUTHOR]

Torque teno virus (TTV) has been proposed as a surrogate biomarker of T-cell function in allogeneic–haematopoietic–stem-cell transplantation (allo-HSCT). Conflicting data exists regarding the value of TTV to assess the degree of immunosuppression. The aim of the present study was to investigate the correlation between TTV viral load and immune function. Using samples from a prospective cohort composed of healthy-volunteers (HV) and allo-HSCT recipients at 6 months post-transplantation, we assessed the correlation between TTV viraemia and immune cell counts or T-cell proliferation capacity post-phytohaemagglutinin stimulation. TTV viraemia was detected in 68% of HV (n = 80) and 100% of allo-HSCT recipients (n = 41; p < 0.001); it was significantly higher in allo-HSCT recipients (3.9 vs. 2.1 Log copies/mL, p < 0.001). There was no correlation between T-cell function and CD3+T-cell count (rho: 0.002) suggesting that T-cell count can normalise without full functional recovery. Furthermore, no significant correlation was observed between TTV viraemia and absolute total/subset lymphocyte counts (rho: <0.13). The highest correlation was observed between TTV viral load and T-cell proliferation capacity (rho: −0.39). We therefore report an inverse correlation between T-cell function and TTV viraemia that is independent of T-cell count. Monitoring of TTV viraemia could be a fast suitable option to objectively assess the competence of immune function in at-risk populations. [ABSTRACT FROM AUTHOR]

• M. tuberculosis (MTB) whole-genome sequencing (WGS) accurately predicts susceptibility for first-line anti-TB drugs. • WGS performs better than drug susceptibility testing (DST) for rifampicin and ethambutol low-level resistance. • Line probe assay is less accurate than WGS for anti-TB drug susceptibility prediction. • WGS could replace phenotypic DST in a country with a low prevalence of resistant MTB. Rapid and correct determination of Mycobacterium tuberculosis (MTB) drug susceptibility is a challenge for tuberculosis (TB) management. Phenotypic drug susceptibility testing (DST) remains the reference method but is time consuming. In this study, genotypic prediction of the first-line drug susceptibility profile obtained by whole-genome sequencing (WGS) was compared with that obtained by phenotypic DST and the line probe assay (LPA). All MTB strains isolated from patients during routine practice at the mycobacteria laboratory of Lyon University Hospital, France, between November 2016 and July 2019 were included (n = 274). Isolates were tested for the first-line drugs using phenotypic DST (Mycobacteria Growth Indicator Tube) and for genotypic prediction of the susceptibility profile with LPA and WGS. Considering phenotypic DST as the reference, WGS predicted resistance to rifampicin, isoniazid, ethambutol and pyrazinamide with sensitivities of 100%, 100%, 100% and 93.8%, respectively, and susceptibility to these drugs with specificities of 99.6%, 100%, 98.5% and 100%, respectively. Performance of the LPA was poorer, with sensitivity of 83.3% for rifampicin and 85.7% for isoniazid resistance. Five isolates were classified as susceptible according to phenotypic DST (1 for rifampicin, 4 for ethambutol) while WGS detected resistance mutations in rpoB and embB genes. WGS, used under appropriate quality-control conditions, has good performance to predict the resistance profile for the four first-line drugs and can correct phenotypic DST results. This study highlights the need for future guidelines recommending WGS as the initial tool in routine practice in areas where the prevalences of TB and drug-resistant MTB are low. [ABSTRACT FROM AUTHOR]

The transmission dynamics of tuberculosis involves complex interactions of socio-economic and, possibly, microbiological factors. We describe an analytical framework to infer factors of epidemic success based on the joint analysis of epidemiological, clinical and pathogen genetic data. We derive isolate-specific, genetic distance-based estimates of epidemic success, and we represent success-related time-dependent concepts, namely epidemicity and endemicity, by restricting analysis to specific time scales. The method is applied to analyze a surveillance-based cohort of 1,641 tuberculosis patients with minisatellite-based isolate genotypes. Known predictors of isolate endemicity (older age, native status) and epidemicity (younger age, sputum smear positivity) were identified with high confidence (P < 0.001). Long-term epidemic success also correlated with the ability of Euro-American and Beijing MTBC lineages to cause active pulmonary infection, independent of patient age and country of origin. Our results demonstrate how important insights into the transmission dynamics of tuberculosis can be gained from active surveillance data. [ABSTRACT FROM AUTHOR]

Introduction The incomplete immune recovery upon effective long-term highly active antiretroviral therapy (HAART) has been associated with increased morbidity and mortality in HIV infected patients []. Immune cellular activation, Tregs or very low-level viraemia has been alternatively suspected, but never investigated simultaneously []. Materials and Methods We performed a cross-sectional study in 87 aviraemic patients (men=62, mean CD4+T cells=570/mm3, mean duration of HAART=12 years). Patients with at least 500 CD4+ T cells /mm3 were classified as complete immunological responders (cIR), whereas remaining patients were classified as inadequate immunological responder (iIR). Tregs were characterized based on CD4+CD25highFoxP3+phenotype using a one-step intracellular staining. Effector Tregs and terminal effectors Tregs were respectively defined as CD4+CD25+FoxP3+CD45RA-, and CD4+CD25+FoxP3+CD45RA-HLADR+phenotypes as recently described []. Activated T cells were identified using (i) elevated HLA-DR expression for CD4+T cells, and (ii) increased expressions of HLA-DR, or CD38, or both (HLADR+CD38+cells) for CD8+T cells. Very low-level viraemia was defined as detectable viraemia between 1 and 39 cp/mL. Univariate and multivariate analyses were performed to identify determinants of iIR. Results Thirty-nine patients were classified as iIR, and 48 as cIR. Patients from the iIR group were significantly older (55 vs 50 years, p=0.027), and had percentages of activated CD4+ T cells, Tregs, effector Tregs and terminal effector Tregs significantly higher (5.3 vs 4%, p=0.014; 9 vs 7.5%, p=0,022; 8 vs 6.3%, p=0.01 and 1.8 vs 1.3%, p=0,033 among CD4+T cells, respectively). Neither the percentage of activated CD8+T cell nor very low-level viraemia were found to be associated with iIR. In the multivariate analysis, nadir of CD4+T cell count and percentage of Tregs were the only two parameters independently associated with iIR (OR=2.339, p=0.001, and OR=0.803, p=0.041, respectively). Conclusions We present here the largest study investigating simultaneously immune response to long-term HAART, immune activation of CD4+ and CD8+ T cells, Tregs percentages and very low-level viraemia. Our results highlight the importance of Tregs in CD4 homeostasis. This aspect should now be prospectively explored in a large cohort of patients. [ABSTRACT FROM AUTHOR]