BackgroundPatients with Mycobacterium avium complex (MAC) lung disease (LD) have a heterogeneous prognosis. This study aimed to develop and validate a prognostic scoring model for these patients using independent risk factors for survival.MethodsWe retrospectively analyzed the data of patients with MAC-LD from two hospitals (cohort 1, n = 368; cohort 2, n = 118). Cohort 1 was evaluated using a multivariate Cox proportional hazards model to identify independent risk factors for overall survival (OS). A prognostic scoring model composed of these factors was developed, and cohort 1 was stratified into three groups according to risk using the log-rank test. Finally, the prognostic scoring model was validated using the data of cohort 2.ResultsSeven independent risk factors for OS were selected from cohort 1, including the male sex, age ≥ 70 years, the presence of a malignancy, body mass index <18.5 kg/m2, lymphocyte count <1000 cells/μL, serum albumin levels <3.5 g/dL, and fibrocavitary disease. The areas under the receiver operating characteristic curves for the prognostic scoring model were 0.84 [95% confidence interval (CI), 0.80 − 0.89] for cohort 1 and 0.84 (95% CI, 0.75 − 0.92) for cohort 2. The 5-year OS rates of patients stratified into low-risk, intermediate-risk, and high-risk groups were 97.6, 76.6, and 30.8%, respectively (P < 0.001), in cohort 1, and 97.2, 82.3, and 45.4%, respectively (P < 0.001), in cohort 2.ConclusionsThis study is the first to develop and validate a prognostic scoring model for patients with MAC-LD. This model may prove useful in clinical settings and practical in estimating the prognosis.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-017-2544-0) contains supplementary material, which is available to authorized users.

PurposeEpisodic nocturnal hypercapnia (eNH) caused by rapid eye movement (REM) sleep-related hypoventilation is often noted in patients with advanced COPD. The purpose of this study was to clarify the clinical significance of eNH and the effectiveness of eNH-targeted noninvasive positive pressure ventilation (NPPV).Patients and methodsWe enrolled patients with stable, severe, or very severe COPD with daytime arterial partial oxygen pressure PaO2 ≥55 mmHg and daytime arterial partial carbon dioxide pressure PaCO2 <55 mmHg, who underwent overnight transcutaneous carbon dioxide pressure (PtcCO2) monitoring from April 2013 to April 2016. We retrospectively compared clinical characteristics, daytime blood gas analysis, frequency of exacerbation, serum albumin levels, and ratio of pulmonary artery to aorta diameter (PA:A ratio), between patients with COPD with and without eNH. For those with eNH, we applied NPPV and compared these clinical characteristics before and after NPPV.ResultsTwenty-one patients were finally included in this study. Ten patients (47.6%) were evaluated to have eNH. These patients had lower albumin levels (p=0.027), larger PA:A ratio (p=0.019), and higher frequency of exacerbations during the last year (p=0.036). NPPV for the patients with eNH improved daytime PaCO2 compared with that 12 months after NPPV (p=0.011). The frequency of exacerbations 1 year before NPPV decreased 1 year after NPPV (p=0.030). Serum albumin levels improved 1 year after NPPV (p=0.001).ConclusionIn patients with stable severe or very severe COPD, eNH may be a risk factor of exacerbations, hypoalbuminemia, and pulmonary hypertension. NPPV may be effective against hypoalbuminemia and acute exacerbations. However, further study is necessary to validate these findings.

Background: Ceftriaxone (CTRX) and ampicillin/sulbactam (ABPC/SBT) are recommended by various guidelines as the first-line antibiotics for community-acquired pneumonia (CAP). However, which of these antibiotics is more effective for treating non-aspiration CAP remains unclear. Methods: This study was a prospective, single-center, open-label, quasi-randomized controlled trial. Patients with adult CAP without risk for aspiration were allocated to either a CTRX or ABPC/SBT group based on the date of hospital admission. Macrolide was added to patients in each group. The primary outcome was the clinical response in the validated per-protocol (VPP) population at end of treatment (EOT). The secondary outcomes were clinical response during treatment and at end of study (EOS) in the VPP population, and mortality rate at day 30 in the modified intention-to-treat (MITT) population.

The discriminative power of CURB-65 for mortality in community-acquired pneumonia (CAP) is suspected to decrease with age. However, a useful prognostic prediction model for older patients with CAP has not been established. This study aimed to develop and validate a new scoring system for predicting mortality in older patients with CAP. We recruited two prospective cohorts including patients aged ≥ 65 years and hospitalized with CAP. In the derivation (n = 872) and validation cohorts (n = 1,158), the average age was 82.0 and 80.6 years and the 30-day mortality rate was 7.6% (n = 66) and 7.4% (n = 86), respectively. A new scoring system was developed based on factors associated with 30-day mortality, identified by multivariate analysis in the derivation cohort. This scoring system named CHUBA comprised five variables: confusion, hypoxemia (SpO2 ≤ 90% or PaO2 ≤ 60 mmHg), blood urea nitrogen ≥ 30 mg/dL, bedridden state, and serum albumin level ≤ 3.0 g/dL. With regard to 30-day mortality, the area under the receiver operating characteristic curve for CURB-65 and CHUBA was 0.672 (95% confidence interval, 0.607–0.732) and 0.809 (95% confidence interval, 0.751–0.856; P < 0.001), respectively. The effectiveness of CHUBA was statistically confirmed in the external validation cohort. In conclusion, a simpler novel scoring system, CHUBA, was established for predicting mortality in older patients with CAP.

A standard treatment regimen against Mycobacteroides abscessus complex (MABC) infections has not yet been established, making MABC difficult to treat successfully. In this study, we sought to develop an active ingredient for the clinical treatment of MABC infections. Methods: We screened 102 MABC strains isolated from clinical specimens using DNA sequence analysis with the housekeeping genes hsp65 and rpoB. Drug susceptibility testing was performed against two subspecies-Mycobacteroides abscessus subsp. abscessus (M. abscessus) and Mycobacteroides abscessus subsp. massiliense (M. massiliense)-using eight antimicrobial agents (clarithromycin, amikacin, doxycycline, imipenem, linezolid, moxifloxacin, faropenem, and rifampicin). The combined efficacy of the antimicrobial agents was investigated using a checkerboard method. Results: We identified 51 isolates as M. abscessus, 46 as M. massiliense, and five as others. Most of the M. abscessus isolates (83.0 %) exhibited inducible resistance to clarithromycin via the expression of the erm (41) gene. Combinations of imipenem with linezolid, moxifloxacin, and rifampicin exhibited additive effects against 81.0 %, 40.7 %, and 26.9 % of M. abscessus, respectively, and against 54.5 %, 69.2 %, and 30.8 % of M. massiliense, respectively. Conclusions: These results demonstrated the potential efficacy of a regimen containing imipenem against M. abscessus and M. massiliense infections.