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Differencing of digital surface models derived from structure from motion (SfM) processing of airborne imagery has been used to produce snow depth (SD) maps with between ∼ 2 and ∼ 15 cm horizontal resolution and accuracies of ±10 cm over relatively flat surfaces with little or no vegetation and over alpine regions. This study builds on these findings by testing two hypotheses across a broader range of conditions: (i) that the vertical accuracy of SfM processing of imagery acquired by commercial low-cost unmanned aerial vehicle (UAV) systems can be adequately modelled using conventional photogrammetric theory and (ii) that SD change can be more accurately estimated by differencing snow-covered elevation surfaces rather than differencing a snow-covered and snow-free surface. A total of 71 UAV missions were flown over five sites, ranging from short grass to a regenerating forest, with ephemeral snowpacks. Point cloud geolocation performance agreed with photogrammetric theory that predicts uncertainty is proportional to UAV altitude and linearly related to horizontal uncertainty. The root-mean-square difference (RMSD) over the observation period, in comparison to the average of in situ measurements along ∼ 50 m transects, ranged from 1.58 to 10.56 cm for weekly SD and from 2.54 to 8.68 cm for weekly SD change. RMSD was not related to microtopography as quantified by the snow-free surface roughness. SD change uncertainty was unrelated to vegetation cover but was dominated by outliers corresponding to rapid in situ melt or onset; the median absolute difference of SD change ranged from 0.65 to 2.71 cm. These results indicate that the accuracy of UAV-based estimates of weekly snow depth change was, excepting conditions with deep fresh snow, substantially better than for snow depth and was comparable to in situ methods.

Background: Recent studies report very low adherence of practitioners to ATS/IDSA recommendations for the treatment of nontuberculous mycobacteria pulmonary disease (NTM-PD), as well as a great variability of practices. Type of management could impact prognosis., Methods: To evaluate management and prognosis of patients with NTM-PD cases with respect to ATS recommendations, we conducted a multicenter retrospective cohort study (18 sentinel sites distributed throughout France), over a period of six years. We collected clinical, radiological, microbiological characteristics, management and outcome of the patients (especially death or not)., Results: 477 patients with NTM-PD were included. Respiratory comorbidities were found in 68% of cases, tuberculosis sequelae in 31.4% of patients, and immunosuppression in 16.8% of cases. The three most common NTM species were Mycobacterium avium complex (60%), M. xenopi (20%) and M. kansasii (5.7%). Smear-positive was found in one third of NTM-PD. Nodulobronchiectatic forms were observed in 54.3% of cases, and cavitary forms in 19.1% of patients. Sixty-three percent of patients were treated, 72.4% of patients with smear-positive samples, and 57.5% of patients with smear-negative samples. Treatment was in adequacy with ATS guidelines in 73.5%. The 2-year mortality was 14.4%. In the Cox regression, treatment (HR = 0.51), age (HR = 1.02), and M. abscessus (3.19) appeared as the 3 significant independent prognostic factors., Conclusion: These findings highlight the adequacy between French practices and the ATS/IDSA guidelines. Treatment was associated with a better survival., (© 2021. The Author(s).)

Background: Clostridium difficile infection (CDI) is associated with a substantial Quality of life impact on patients that has not been so far measured with a generic validated instrument., Methods: A prospective study was performed in 7 French acute-care settings in patients presenting with a bacteriologically-confirmed CDI. The EQ-5D-3 L was filled in by patients at 7 ± 2 days after CDI diagnosis to describe their state of health at that date as well as their state of health immediately before the CDI episode (baseline). Individual utility decrement was obtained by subtracting the corresponding utilities. The Quality Adjusted Life Year (QALY) loss was calculated by multiplying the days spent from baseline to the date of the interview, by the decrement of utility. A multivariate analysis of variance of the utility decrement according to CDI and patients characteristics was performed., Results: Eighty patients were enrolled (mean age: 69.4 years, 55% females). The utility scores dropped from a mean 0.542 (SD: 0.391) at baseline to 0.050 (SD: 0.404) during the CDI episode with a mean adjusted utility decrement of 0.492 (SD: 0.398) point. This decrement increased significantly with CDI severity (Zar score ≥ 3) (p = 0.001), in patients with a positive baseline utility (p = 0.032), in women as compared to men (p = 0.041) and in patients aged more than 65 years (p = 0.041). No association with the Charlson index was found. The associated QALY loss not integrating the excess mortality was 0.028 (SD: 0.053)., Conclusions: The impact on quality of life of CDI episodes is major and translates in a substantial QALY loss despite their short duration.

Background: Preterm delivery during pregnancy (<37 weeks' gestation) is a leading cause of perinatal mortality and morbidity. Treating bacterial vaginosis during pregnancy can reduce poor outcomes, such as preterm birth. We aimed to investigate whether treatment of bacterial vaginosis decreases late miscarriages or spontaneous very preterm birth., Methods: PREMEVA was a double-blind randomised controlled trial done in 40 French centres. Women aged 18 years or older with bacterial vaginosis and low-risk pregnancy were eligible for inclusion and were randomly assigned (2:1) to three parallel groups: single-course or triple-course 300 mg clindamycin twice-daily for 4 days, or placebo. Women with high-risk pregnancy outcomes were eligible for inclusion in a high-risk subtrial and were randomly assigned (1:1) to either single-course or triple-course clindamycin. The primary outcome was a composite of late miscarriage (16-21 weeks) or spontaneous very preterm birth (22-32 weeks), which we assessed in all patients with delivery data (modified intention to treat). Adverse events were systematically reported. This study is registered with ClinicalTrials.gov, number NCT00642980., Findings: Between April 1, 2006, and June 30, 2011, we screened 84 530 pregnant women before 14 weeks' gestation. 5630 had bacterial vaginosis, of whom 3105 were randomly assigned to groups in the low-risk trial (n=943 to receive single-course clindamycin, n=968 to receive triple-course clindamycin, and n=958 to receive placebo) or high-risk subtrial (n=122 to receive single-course clindamycin and n=114 to receive triple-course clindamycin). In 2869 low-risk pregnancies, the primary outcome occurred in 22 (1·2%) of 1904 participants receiving clindamycin and 10 (1·0%) of 956 participants receiving placebo (relative risk [RR] 1·10, 95% CI 0·53-2·32; p=0·82). In 236 high-risk pregnancies, the primary outcome occurred in 5 (4·4%) participants in the triple-course clindamycin group and 8 (6·0%) participants in the single-course clindamycin group (RR 0·67, 95% CI 0·23-2·00; p=0·47). In the low-risk trial, adverse events were more common in the clindamycin groups than in the placebo group (58 [3·0%] of 1904 vs 12 [1·3%] of 956; p=0·0035). The most commonly reported adverse event was diarrhoea (30 [1·6%] in the clindamycin groups vs 4 [0·4%] in the placebo group; p=0·0071); abdominal pain was also observed in the clindamycin groups (9 [0·6%] participants) versus none in the placebo group (p=0·034). No severe adverse event was reported in any group. Adverse fetal and neonatal outcomes did not differ significantly between groups in the high-risk subtrial., Interpretation: Systematic screening and subsequent treatment for bacterial vaginosis in women with low-risk pregnancies shows no evidence of risk reduction of late miscarriage or spontaneous very preterm birth. Use of antibiotics to prevent preterm delivery in this patient population should be reconsidered., Funding: French Ministry of Health., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Among risk factors of prematurity, bacterial vaginosis (BV) could play an important role, but few studies took place in our country., Aim: In a French population of women booking in a hospital maternity, to search a link between prematurity and BV in the first trimester of pregnancy., Methods: A hospital cohort study was carried out between May 2006 and September 1(st), 2009. Pregnant women were screening for BV before 13+6 weeks' gestation. BV was determined by a Gram-Stained Vaginal score greater or equal to 7., Results: One thousand three hundred and thirty-six patients were included in the study among whom 203 patients had BV and 1133 patients did not have. The presence of BV was significantly associated with preterm delivery (OR: 1.6; 95% IC: 1.1-2.7). But this increase concerned only the spontaneous prematurity (ORa: 1.8, 95% IC: 1.0-3.2) and the statistical association disappeared after taking into account maternal tobacco addiction and socio-economic weak level (ORa: 1.6; 95% IC: 0.9-2.9). At the patient with BV, moreover, the risk of miscarriage before 16SA was significantly augmented at the patient with BV (OR: 3.4; 95% IC: 1.1-10.4), but this risk disappeared after taking into account tobacco addiction and maternal level of studies (ORa: 1.9; 95% IC: 0.5-7.2)., Conclusion: The presence of BV in the first trimester of pregnancy seems to be associated with increased risks of preterm delivery and early spontaneous miscarriage. However, this relation seems to be partly linked to a level of weaker study and a more frequent tobacco addiction among the women with BV., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

An aminoglycoside in association with beta-lactam antibiotic are usually the most efficient treatment for Pseudomonas aeruginosa infections in cystic fibrosis patients. Tobramycin has the lower MICs than the other aminoglycosides to Pseudomonas aeruginosa. The aim of the work was to compare pharmacokinetics of tobramycin after once daily (15 mg/kg/day; 11 patients) or thrice daily dose (5 mg/kg/day; 9 patients) in combination ceftazidime (CAZ 200 mg/day in 3 inj. IVD) in sputum and sera for two weeks. No statistical difference in the serum concentration obtained in each group of patients was observed between the first and the 14th day. Serum concentrations were three fold higher when tobramycin was administered in once daily dose. Low through concentrations were quickly obtained, but they were slightly higher after thrice daily doses. Bronchial concentrations were 2 to 2.5 superior and near the critical concentration of tobramycin. The clinical efficacy were comparable in the two regimens.

The bactericidal activity of cefpirome (CPO)-aminoglycoside (AG) combination was assessed by a kinetic time-kill method against 8 strains of Pseudomonas aeruginosa showing intermediate susceptibility to cefpirome (MICS: 8-32 mg/l). Six strains had an acquired beta-lactam resistance mechanism (moderate cephalosporinase hyperproduction, OXA-2 or PSE-1 enzyme production, non enzymatic resistance) and one strain was resistant to tobramycin (TOB). Antibiotic concentrations used for time-kill curves were 1/2, 1 and 2x MIC for cefpirome, 8 mg/l for tobramycin and 16 mg/l for amikacin (AKN). Bactericidal activity was defined as a (4 log10 reduction of the initial inoculum. At the concentrations used in this study, CPO was not bactericidal; AG were bactericidal in 3 to 24 hours. CPO-AG combination was bactericidal against all the strains with no secondary regrowth. For 7/8 strains, the combination of CPO with TOB and/or AKN was more rapidly bactericidal than the AG alone. In conclusion, despite an intermediate susceptibility against numerous strains of P. aeruginosa, the CPO-AG combination is bactericidal at concentrations achievable with standard dosing regimens in man.

A single daily dose of amikacin 35 mg/kg by i.v. infusion over 30 min in 18 cystic fibrosis patients achieved mean serum peak and trough concentrations of 121.4 mg/L (+/- 37.3) and 0.88 mg/L (+/- 0.62), respectively. Pharmacokinetic parameters and bronchial diffusion of amikacin showed marked inter-patient variability. The highest concentrations in sputum were obtained at 2 h (10.95 +/- 7.55 mg/L) and decreased slowly to reach a mean concentration of 2.14 mg/L (range 0.2-3.8 mg/L) just before the following infusion. An increase in the body clearance of amikacin and a decrease in the volume of distribution according to age were observed.

The interest of the treatment with a single daily dose of amikacin (AMK) in cystic fibrosis (CF) patients with P. aeruginosa infections has been much debated. The aim of work was to study the efficiency of this treatment on (CF) patients with chronic bronchopulmonary P. aeruginosa infections previously treated for two weeks with the combination ceftazidime (CAZ 200 mg/day in 3 inj. IVD) and AMK (35 mg/day in one IV perf. of 30 minutes). The bacteriological supervision of this treatment was performed 1: by the determination of MICs before and after treatment, 2: by the decrease of P. aeruginosa colonization immediately after this treatment and during 11 months, 3: by the identification of P. aeruginosa strains with phenotypic methods (serotyping and antibiotyping) and with genotypic method (pulsed field gel electrophoresis). The use of AMK in a single daily dose in order to treat chronic lung infections colonized with P. aeruginosa susceptible to this antibiotic shows encouraging results as far as bacteriology is concerned: this treatment has given means to reduce colonization for a month in 15 of 18 patients. For 9 of the 18 patients, no P. aeruginosa strains were isolated for nine months. The serotyping and antibiotyping systems do not enable us to study the P. aeruginosa epidemiology. Genome macrorestriction fingerprinting of P. aeruginosa in pulsed field gel electrophoresis confirms that patient with CF were colonized with one or several clones. In our study no variation of these clones was noticed for the first eleven months. Genome macrorestriction fingerprinting appears to be one of the most effective methods for delineate strains of P. aeruginosa colonizing CF patients.