Probabilistic chemotherapy in knee and hip replacement infection: the place of linezolid

Prosthetic joint infection (PJI) can occur with a wide range of microorganisms and clinical features. After replacement surgery of prosthetic joint, prescription of probabilistic broad-spectrum antimicrobial therapy is usual, while awaiting microbial culture results. The aim of our study was to describe the antibiotic susceptibility of microorganisms isolated from hip and knee PJI. The data were collected to determine the best alternative to the usual combination of piperacillin-tazobactam (TZP) or cefotaxime (CTX) and vancomycin (VAN). Based on a French prospective, multicenter study, we analyzed microbiological susceptibility to antibiotics of 183 strains isolated from patients with confirmed hip or knee PJI. In vitro susceptibility was evaluated: TZP+VAN, TZP+linezolid (LZD), CTX+VAN, and CTX+LZD. We also analyzed resistance to different antibiotics commonly used as oral alternatives. Among the 183 patients with PJI, 62 (34%) had a total knee prosthesis, and 121 (66%) a hip prosthesis. The main identified bacteria were Staphylococcus aureus (32.2% of isolates), coagulase-negative staphylococci (27.3%), Enterobacteriaceae (14.2%), and Streptococcus (13.7%). Infections were polymicrobial for 28 (15.3%) patients. All combinations were highly effective: CTX+VAN, CTX+LZD, TZP+VAN, and TZP+LZD (93.4%, 94%, 98.4%, and 98.9% of all cases respectively). Use of LZD instead of VAN in combination with a broad-spectrum beta-lactam covers almost all of the bacteria isolated in PJI. This association should be considered in probabilistic chemotherapy, as it is particularly easy to use (oral administration and no vancomycin monitoring)

Multicentre prospective evaluation of histological and molecular criterion for diagnosis of prosthetic-joint infection

Objectives: This multicenter prospective study was performed to assess the contribution of broad range PCR diagnosis in prosthetic-joint infection (PJI). Methods: Adult patients treated for PJI at 7 centers were included between December 2010 and March 2012. Six per-operative samples were obtained for each patient, 5 for conventional cultures and 16S rRNA gene real-time PCR followed by sequencing, and 1 for histopathological classification according to Morawietz. Cultures and PCR were performed in a highly standardized manner, with 3 quality controls of PCR analyses. An infection was considered as proved (3 criteria: per-operative, bacteriological and histological), probable (clinical or bacteriological criterium), or excluded (no criterium). Molecular criterium for predicting PJI was determined using the bacteriological one as reference (>=1 positive sample for virulent organism, and >=3 positive samples for coagulase-negative staphylococci (CoNS) and P. acnes). Results: 299 patients were included, 264 with suspicion of sepsis (S) and 35 as controls (C). The 264 S presented with acute (19%), or chronic suspicion of PJI (81%). Infection was proved or probable in 212/264 S (80%), with the bacteriological criterium in 189/212 S (89%). Out of these, 156 (83%) had monomicrobial and 33 (17%) polymicrobial infections. The isolated pathogens were S. aureus (40%), CoNS (25%), streptococci (14%), Gram-Negative rods (10%), and anaerobes 8%. Histology results were not available for 55 patients, leaving 244 patients available for analysis. Histological findings of infection (Morawietz types II or III) were present in 128/169 (76%) proved or probable infections, in 3 patients without any other criterium, and were absent in excluded infections (n=42) and controls (n=29). PCR results were not analysable for 32 patients (S=28, C=4), leaving 267 patients (S=236, C=31) available for analysis. Molecular criterium of infection was present in 63/68 (93%) proved infections, 83/124 (67%) probable infections, 3/42 excluded infections, 0/2 histological criterium alone and 2/31 controls. Molecular criterium of infection was absent in 34/189 (18%) culture-positive S, and present in 8/23 culture-negative S (8 patients treated with antibiotics). Conclusions: According to this multicenter prospective study, 16S rRNA gene real-time PCR is less susceptible than culture for diagnosis of PJI. Molecular analysis could be recommended in culture-negative patients who were receiving antibiotics

Evaluation of 16S rRNA gene PCR sensitivity and specificity for diagnosis of prosthetic joint infection: a prospective multicenter cross-sectional study

There is no standard method for the diagnosis of prosthetic joint infection (PJI). The contribution of 16S rRNA gene PCR sequencing on a routine basis remains to be defined. We performed a prospective multicenter study to assess the contributions of 16S rRNA gene assays in PJI diagnosis. Over a 2-year period, all patients suspected to have PJIs and a few uninfected patients undergoing primary arthroplasty (control group) were included. Five perioperative samples per patient were collected for culture and 16S rRNA gene PCR sequencing and one for histological examination. Three multicenter quality control assays were performed with both DNA extracts and crushed samples. The diagnosis of PJI was based on clinical, bacteriological, and histological criteria, according to Infectious Diseases Society of America guidelines. A molecular diagnosis was modeled on the bacteriological criterion (≥ 1 positive sample for strict pathogens and ≥ 2 for commensal skin flora). Molecular data were analyzed according to the diagnosis of PJI. Between December 2010 and March 2012, 264 suspected cases of PJI and 35 control cases were included. PJI was confirmed in 215/264 suspected cases, 192 (89%) with a bacteriological criterion. The PJIs were monomicrobial (163 cases [85%]; staphylococci, n = 108; streptococci, n = 22; Gram-negative bacilli, n = 16; anaerobes, n = 13; others, n = 4) or polymicrobial (29 cases [15%]). The molecular diagnosis was positive in 151/215 confirmed cases of PJI (143 cases with bacteriological PJI documentation and 8 treated cases without bacteriological documentation) and in 2/49 cases without confirmed PJI (sensitivity, 73.3%; specificity, 95.5%). The 16S rRNA gene PCR assay showed a lack of sensitivity in the diagnosis of PJI on a multicenter routine basis

Management of Polypoid Gallbladder Lesions in Children: A Multicenter Study

INTRODUCTION:  Polypoid lesions of the gallbladder (PLG) are relatively common in adults, while they are very rare in children. The use of high-quality ultrasonography leads to increased detection of PLG, although less than 20 pediatric cases of primary PLG have been reported in the literature. The aim of this study was to address the experience of PLG management in children. MATERIALS AND METHODS:  A retrospective multicenter review of children with ultrasonographically defined PLG between 2006 and 2016 was performed. The data from 12 pediatric surgery centers were compiled for this purpose. RESULTS:  Eighteen patients (mean age: 10.4 ± 4.1 years) were included and managed according to each center\u27s protocols. Cholecystectomy was performed for nine symptomatic patients. Histopathology conclusively revealed four tubular and five papillary adenomas, with a median size of 12 mm (ranging from 3 to 35 mm). Nine asymptomatic children were monitored by sonography over a 24-month (ranging from 12 to 66 months) follow-up period. The median PLG size was 7 mm (ranging from 3 to 9 mm). Two lesions disappeared after 1 and 2 years of follow-up, respectively. None of the patients developed symptoms or malignant transformation. CONCLUSION:  This report confirms appropriate use of a conservative approach with annual clinical and ultrasound follow-up for small-sized and isolated PLG in children given the absence of malignancy and potential vanishing entities. Surgical treatment should be considered in case of lesions larger than 10 mm in size or when they are associated with symptoms

Hydraulic retention time affects bacterial community structure in an As-rich acid mine drainage (AMD) biotreatment process.

Arsenic removal consecutive to biological iron oxidation and precipitation is an effective process for treating As-rich acid mine drainage (AMD). We studied the effect of hydraulic retention time (HRT)-from 74 to 456 min-in a bench-scale bioreactor exploiting such process. The treatment efficiency was monitored during 19 days, and the final mineralogy and bacterial communities of the biogenic precipitates were characterized by X-ray absorption spectroscopy and high-throughput 16S rRNA gene sequencing. The percentage of Fe(II) oxidation (10-47%) and As removal (19-37%) increased with increasing HRT. Arsenic was trapped in the biogenic precipitates as As(III)-bearing schwertmannite and amorphous ferric arsenate, with a decrease of As/Fe ratio with increasing HRT. The bacterial community in the biogenic precipitate was dominated by Fe-oxidizing bacteria whatever the HRT. The proportion of Gallionella and Ferrovum genera shifted from respectively 65 and 12% at low HRT to 23 and 51% at high HRT, in relation with physicochemical changes in the treated water. aioA genes and Thiomonas genus were detected at all HRT although As(III) oxidation was not evidenced. To our knowledge, this is the first evidence of the role of HRT as a driver of bacterial community structure in bioreactors exploiting microbial Fe(II) oxidation for AMD treatment

Trends in incidence, mortality and survival in women with breast cancer from 1985 to 2012 in Granada, Spain: a population-based study

The incidence of breast cancer has increased since the 1970s. Despite favorable trends in prognosis, the role of changes in clinical practice and the introduction of screening remain controversial. We examined breast cancer trends to shed light on their determinants Overall, age-adjusted (European Standard Population) incidence rates increased from 48.0 cases × 100,000 women in 1985–1989 to 83.4 in 2008–2012, with an annual percentage change (APC) of 2.5% (95%CI, 2.1–2.9) for 1985–2012. The greatest increase was in women younger than 40 years (APC 3.5, 95%CI, 2.4–4.8). For 2000–2012 the incidence trend increased only for stage I tumors (APC 3.8, 95%CI, 1.9–5.8). Overall age-adjusted breast cancer mortality decreased (APC − 1, 95%CI, − 1.4 – − 0.5), as did mortality in the 50–69 year age group (APC − 1.3, 95%CI, − 2.2 – − 0.4). Age-standardized net survival increased from 67.5% at 5 years in 1985–1989 to 83.7% in 2010–2012. All age groups younger than 70 years showed a similar evolution. Five-year net survival rates were 96.6% for patients with tumors diagnosed in stage I, 88.2% for stage II, 62.5% for stage III and 23.3% for stage IV. Breast cancer incidence is increasing – a reflection of the evolution of risk factors and increasing diagnostic pressure. After screening was introduced, the incidence of stage I tumors increased, with no decrease in the incidence of more advanced stages. Reductions were seen for overall mortality and mortality in the 50–69 year age group, but no changes were found after screening implementation. Survival trends have evolved favorably except for the 70–84 year age group and for metastatic tumors.This study was supported by a grant from the Acción Estratégica en Salud plan for the High Resolution Project on Prognosis and Care of Cancer Patients (No. AC14/00036) awarded by the Spanish Ministry of Economy and Competitiveness and co-funded by the European Regional Development Fund (ERDF)

PLoS One

The first objective of this study was to determine the GenoType NTM-DR assay performance for subspecies identification in Mycobacterium abscessus complex isolates. The second objective was to evaluate the GenoType NTM-DR assay ability to detect clarithromycin and amikacin resistance in M. abscessus complex isolates compared with drug susceptibility testing (DST) and PCR sequencing of the erm(41), rrl and rrs genes. The concordance between the GenoType NTM-DR and MLST results concerning subspecies identification was 100%. The wild type and mutated alleles of the rrl and rrs genes were detected by the GenoType NTM-DR assay and PCR sequencing with 100% (115/115) agreement. Similarly, 100% concordance between GenoType NTM-DR and DST was observed for clarithromycin and amikacin testing. Sensitivity for the detection of clarithromycin and amikacin resistance was 100%. The GenoType NTM-DR assay provides a robust and complementary tool to the gold standard methods (MLST and broth microdilution) for subspecies identification and drug resistance detection

Biological attenuation of arsenic and iron in a continuous flow bioreactor treating acid mine drainage (AMD)

International audienc

Biomarker-indicated extent of oxidation of plant-derived organic carbon (OC) in relation to geomorphology in an arsenic contaminated Holocene aquifer, Cambodia

The poisoning of rural populations in South and Southeast Asia due to high groundwater arsenic concentrations is one of the world’s largest ongoing natural disasters. It is important to consider environmental processes related to the release of geogenic arsenic, including geomorphological and organic geochemical processes. Arsenic is released from sediments when iron-oxide minerals, onto which arsenic is adsorbed or incorporated, react with organic carbon (OC) and the OC is oxidised. In this study we build a new geomorphological framework for Kandal Province, a highly studied arsenic affected region of Cambodia, and tie this into wider regional environmental change throughout the Holocene. Analyses shows that the concentration of OC in the sediments is strongly inversely correlated to grainsize. Furthermore, the type of OC is also related to grain size with the clay containing mostly (immature) plant derived OC and sand containing mostly thermally mature derived OC. Finally, analyses indicate that within the plant derived OC relative oxidation is strongly grouped by stratigraphy with the older bound OC more oxidised than younger OC