Published papers

We conducted a subgroup analysis of a study on the long-term effects of COVID-19 (long COVID) in Japan to assess the effect of vaccination on long COVID symptoms. We assessed the clinical course of 111 patients with long COVID at the time of vaccination. The follow-up period was one year from the onset of COVID-19 or until the administration of the third vaccine dose. Of the 111 patients, 15 (13.5%) reported improvement, four (3.6%) reported deterioration, and 92 (82.9%) reported no change in their long COVID symptoms after vaccination. The most common long COVID symptoms before vaccination were alopecia, dyspnea, muscle weakness, fatigue, and headache among participants whose symptoms improved. Reduced dyspnea and alopecia were the most frequently reported improvements in symptoms after vaccination. Some symptoms persisted, including sleep disturbance, myalgia, and hypersensitivity. Vaccination did not appear to have a clinically important effect on patients with long COVID symptoms.

BACKGROUND: The long-term exercise tolerance changes in patients with nontuberculous mycobacterial pulmonary disease (NTM-PD) are of great interest because of its chronic course. This study aimed to characterize the associations between changes over time in six-minute walking test (6MWT) parameters and clinical parameters in patients with NTM-PD. METHODS: Overall, 188 patients with NTM-PD, visiting outpatient clinics at Keio University Hospital from April 2012 to March 2020 were included in the study. Data were collected using the St. George's Respiratory Questionnaire (SGRQ), pulmonary function test (PFT), blood tests, and the 6MWT at registration and at least once after that. The association of the anchors and clinical indicators with the 6MWT parameters was assessed. RESULTS: The median age [interquartile range] of the patients was 67 [63-74] years. The median baseline six-minute walk distance (6MWD) and final Borg scale (FBS) were 413 [361-470] m and 1 [0-2], respectively. In the correlation analysis, ΔSGRQ total/year (yr), Δforced vital capacity (FVC, % predicted)/yr, Δforced expiratory volume in 1 s (FEV1, % predicted)/yr, and Δdiffusing capacity for carbon monoxide (DLCO, % predicted)/yr correlated with both Δ6MWD/yr and ΔFBS/yr in the longitudinal analysis (|Rho| > 0.20). When stratified into three quantiles of changes in each anchor, the 6MWT parameters worsened over time in the bottom 25% group by mixed-effects model. Specifically, Δ6MWD was affected by SGRQ activity, SGRQ impacts, PFT (FVC, FEV1, and DLCO), and C-reactive protein (CRP). ΔFBS was affected by all SGRQ components, total score, and PFT. Anchor scores and variables at baseline that worsened Δ6MWD were higher SGRQ scores, lower FVC (% predicted), lower DLCO (% predicted), higher Krebs von den Lungen-6, old age, and undergoing treatment at registration. Similarly, these clinical parameters and elevated CRP, excluding undergoing treatment at registration, worsened ΔFBS. CONCLUSIONS: The decreased walking distance and exacerbation of dyspnea on exertion over time in patients with NTM-PD may reflect a deterioration of health-related quality of life and pulmonary function. Thus, the change in 6MWT over time can be used as an indicator to accurately assess the patient's condition and tailor their healthcare environment.

Background: Although previous cross-sectional studies showed the feasibility and clinical association of the St. George's Respiratory Questionnaire (SGRQ) in Mycobacterium avium complex pulmonary disease (MAC-PD), its longitudinal validity is poorly understood. We aimed to determine the longitudinal validity and prognostic significance of SGRQ. Methods: In this prospective observational study conducted between May 2012 and August 2018, we evaluated 269 enrolled patients with MAC-PD and examined associations between baseline SGRQ total scores and mortality or clinical variables (anchors), including serum C-reactive protein levels and pulmonary function test results. Results: Age- and sex-matched SGRQ scores indicated significantly greater impairment in patients with MAC-PD than in the general population (P < 0.001). On multivariable Cox proportional hazards regression analysis, the SGRQ total score ≥25 was an independent risk factor for mortality (adjusted hazard ratio, 5.90; 95% confidence interval, 1.65–37.7) as well as age, body mass index, and forced vital capacity (FVC). Mixed-effect model results showed a significant association between SGRQ symptom/total scores and forced expiratory volume in 1 s (FEV1), FVC, and diffusing carbon monoxide capacity. Older age, a positive smear, non-nodular/bronchiectatic form, and cavity regions were associated with SGRQ total score deterioration. Patients with a greater decline from baseline FEV1 (% predicted) exhibited significantly worse impairment in the SGRQ total score (mean ± SE, 4.69 ± 10.9 points, P = 0.001). Conclusions: SGRQ showed longitudinal validity in assessing disease severity and was sensitive to changes in patients with MAC-PD, especially changes in %FEV1. The SGRQ total score may be an important prognostic factor.

OBJECTIVE: This study aimed to investigate the utility of CT quantification of lung volume for predicting critical outcomes in COVID-19 patients. METHODS: This retrospective cohort study included 1200 hospitalised patients with COVID-19 from 4 hospitals. Lung fields were extracted using artificial intelligence-based segmentation, and the percentage of the predicted (%pred) total lung volume (TLC (%pred)) was calculated. The incidence of critical outcomes and posthospitalisation complications was compared between patients with low and high CT lung volumes classified based on the median percentage of predicted TLCct (n=600 for each). Prognostic factors for residual lung volume loss were investigated in 208 patients with COVID-19 via a follow-up CT after 3 months. RESULTS: The incidence of critical outcomes was higher in the low TLCct (%pred) group than in the high TLCct (%pred) group (14.2% vs 3.3%, p<0.0001). Multivariable analysis of previously reported factors (age, sex, body mass index and comorbidities) demonstrated that CT-derived lung volume was significantly associated with critical outcomes. The low TLCct (%pred) group exhibited a higher incidence of bacterial infection, heart failure, thromboembolism, liver dysfunction and renal dysfunction than the high TLCct (%pred) group. TLCct (%pred) at 3 months was similarly divided into two groups at the median (71.8%). Among patients with follow-up CT scans, lung volumes showed a recovery trend from the time of admission to 3 months but remained lower in critical cases at 3 months. CONCLUSION: Lower CT lung volume was associated with critical outcomes, posthospitalisation complications and slower improvement of clinical conditions in COVID-19 patients.

The genetic make-up of an individual contributes to the susceptibility and response to viral infection. Although environmental, clinical and social factors have a role in the chance of exposure to SARS-CoV-2 and the severity of COVID-191,2, host genetics may also be important. Identifying host-specific genetic factors may reveal biological mechanisms of therapeutic relevance and clarify causal relationships of modifiable environmental risk factors for SARS-CoV-2 infection and outcomes. We formed a global network of researchers to investigate the role of human genetics in SARS-CoV-2 infection and COVID-19 severity. Here we describe the results of three genome-wide association meta-analyses that consist of up to 49,562 patients with COVID-19 from 46 studies across 19 countries. We report 13 genome-wide significant loci that are associated with SARS-CoV-2 infection or severe manifestations of COVID-19. Several of these loci correspond to previously documented associations to lung or autoimmune and inflammatory diseases3–7. They also represent potentially actionable mechanisms in response to infection. Mendelian randomization analyses support a causal role for smoking and body-mass index for severe COVID-19 although not for type II diabetes. The identification of novel host genetic factors associated with COVID-19 was made possible by the community of human genetics researchers coming together to prioritize the sharing of data, results, resources and analytical frameworks. This working model of international collaboration underscores what is possible for future genetic discoveries in emerging pandemics, or indeed for any complex human disease.

PURPOSE: Patients' values and priorities in their lives should be appreciated from an early phase of incurable diseases such as advanced cancer. However, studies examining these characteristics have been lacking. This study attempted to determine what patients with advanced lung cancer valued most, once they had been diagnosed, and any associated factors. METHODS: Patients with newly diagnosed advanced lung cancer (N = 248) were enrolled in a questionnaire survey conducted at 16 hospitals in Japan. Their priorities were assessed using a free-text response to the question what is the most important thing to you now? at the time of diagnosis and 3 months after diagnosis. The free-text responses were classified into 10 categories for quantification. The clinical characteristics associated with the category describing daily life were further examined. RESULTS: Free-text comments were obtained from 103 (44.0%) and 66 (42.6%) patients at the time of diagnosis and at 3 months, respectively. The most frequent categories were family (at diagnosis: 50.5%; at 3 months: 50.0%) and daily life (at diagnosis: 33.0%; at 3 months: 36.4%), followed by health (at diagnosis: 32.0%; at 3 months: 27.3%) at both time points. The patients mentioning daily life, the issues related to how to spend daily life, showed significantly higher total scores and functional well-being subscale scores on the Functional Assessment of Cancer Therapy-Lung scale at both time points and lower depression scores at diagnosis and lower anxiety scores at 3 months on the Hospital Anxiety and Depression Scale. CONCLUSION: Family and daily life were highly valued by patients with advanced lung cancer at diagnosis. A better quality of life and better mood were associated with mentioning daily life, which should be taken into account in care planning to maintain patients' involvement in daily life even with incurable diseases.

BACKGROUND: Mycobacterium abscessus (M. abscessus) is a rapidly growing bacterium (RGM) that causes refractory pulmonary and extrapulmonary infections. However, studies investigating pharyngeal and laryngeal M. abscessus infections are limited. CASE PRESENTATION: A 41-year-old immunocompetent woman complaining of bloody sputum was referred to our hospital. Although her sputum culture tested positive for M. abscessus subsp. abscessus, radiological findings were not indicative of pulmonary infection or sinusitis. Further diagnostic workup, including laryngeal endoscopy and positron emission tomography/computed tomography (PET/CT), confirmed the presence of nasopharyngeal M. abscessus infection. The patient was initially treated with intravenous amikacin, imipenem/cilastatin, azithromycin, and clofazimine for 28 days, after which the patient was provided with amikacin, azithromycin, clofazimine, and sitafloxacin for four months. After the completion of antibiotic therapy, the patient showed negative results on sputum smear and culture and normal findings on PET/CT and laryngeal endoscopy. Whole-genome sequencing of this strain revealed that it belonged to the ABS-GL4 cluster, which has a functional erythromycin ribosomal methylase gene, although it is not a major lineage in non-cystic fibrosis (CF) patients in Japan and Taiwan and in CF patients in European countries. We conducted a literature review and identified seven patients who developed pharyngeal/laryngeal non-tuberculous mycobacterium (NTM) infection. Four of the eight patients had a history of immunosuppressant use, including steroids. Seven of the eight patients responded well to their treatment regimens. CONCLUSION: Patients whose sputum culture tests are positive for NTM and who meet the diagnostic criteria for NTM infection but do not have intrapulmonary lesions should be evaluated for otorhinolaryngological infections. Our case series revealed that immunosuppressant use is a risk factor for pharyngeal/laryngeal NTM infection and that patients with pharyngeal/laryngeal NTM infections respond relatively well to antibiotic therapy.

BACKGROUND: Since nontuberculous mycobacterial pulmonary disease (NTM-PD) is common in middle-aged/elderly slender women at risk of osteoporosis, we hypothesized that NTM-PD could be associated with osteoporosis. The study aimed to evaluate the prevalence of osteoporosis in patients with NTM-PD compared with that in the general population and determine the factors associated with osteoporosis in the subjects, including the serum estradiol (E2) and 25-hydroxyvitamin D (25OHD) levels. METHODS: We have recruited 228 consecutive adult patients with NTM-PD from a prospective cohort study at the Keio University Hospital, who had no history of osteoporosis or osteoporosis-associated bone fracture but underwent dual-energy X-ray absorptiometry-based bone mineral density (BMD) evaluation from August 2017-September 2019. The E2 and 25OHD levels were measured in 165 patients with available stored serum samples. We performed multivariable logistic regression analyses for osteopenia and osteoporosis. RESULTS: Osteoporosis (T-score ≤  - 2.5) and osteopenia (T-score - 1 to - 2.5) were diagnosed in 35.1% and 36.8% of patients with NTM-PD, respectively. Compared with the general population, the proportion of osteoporosis was significantly higher in 50-59-, 60-69-, and 70-79-year-old women with NTM-PD. Multivariable analysis revealed that older age (adjusted odds ratio [aOR] for 1-year increase = 1.12; 95% confidence interval [CI] = 1.07-1.18), female sex (aOR = 36.3; 95% CI = 7.57-174), lower BMI (aOR for 1 kg/m2 decrease = 1.37; 95% CI = 1.14-1.65), and chronic Pseudomonas aeruginosa (PA) infection (aOR = 6.70; 95% CI = 1.07-41.8) were independently associated with osteoporosis. Additionally, multivariable analysis in 165 patients whose serum E2 and 25OHD levels were measured showed that both low E2 levels (< 10 pg/mL) and lower 25OHD levels were independently associated with osteoporosis. CONCLUSIONS: Middle-aged/elderly women with NTM-PD have a higher prevalence of osteoporosis than the general population. BMD screening should be considered in NTM-PD, especially in older females with severe diseases such as chronic PA infection and lower BMI, and low serum E2 and 25OHD levels.

Predictive models for determining coronavirus disease 2019 (COVID-19) severity have been established; however, the complexity of the interactions among factors limits the use of conventional statistical methods. This study aimed to establish a simple and accurate predictive model for COVID-19 severity using an explainable machine learning approach. A total of 3,301 patients ≥ 18 years diagnosed with COVID-19 between February 2020 and October 2022 were included. The discovery cohort comprised patients whose disease onset fell before October 1, 2020 (N = 1,023), and the validation cohort comprised the remaining patients (N = 2,278). Pointwise linear and logistic regression models were used to extract 41 features. Reinforcement learning was used to generate a simple model with high predictive accuracy. The primary evaluation was the area under the receiver operating characteristic curve (AUC). The predictive model achieved an AUC of ≥ 0.905 using four features: serum albumin levels, lactate dehydrogenase levels, age, and neutrophil count. The highest AUC value was 0.906 (sensitivity, 0.842; specificity, 0.811) in the discovery cohort and 0.861 (sensitivity, 0.804; specificity, 0.675) in the validation cohort. Simple and well-structured predictive models were established, which may aid in patient management and the selection of therapeutic interventions.

RATIONALE: The incidence and sites of mucus accumulation, and molecular regulation of mucin gene expression, in COVID-19 lung disease have not been reported. OBJECTIVES: Characterize incidence of mucus accumulation and the mechanisms mediating mucin hypersecretion in COVID-19 lung disease. METHODS: Airway mucus and mucins were evaluated in COVID-19 autopsy lungs by AB-PAS and immunohistochemical staining, RNA in situ hybridization, and spatial transcriptional profiling. SARS-CoV-2-infected human bronchial epithelial (HBE) cultures were utilized to investigate mechanisms of SARS-CoV-2-induced mucin expression and synthesis and test candidate countermeasures. MEASUREMENTS AND MAIN RESULTS: MUC5B and variably MUC5AC RNA levels were increased throughout all airway regions of COVID-19 autopsy lungs, notably in the sub-acute/chronic disease phase following SARS-CoV-2 clearance. In the distal lung, MUC5B-dominated mucus plugging was observed in 90% of COVID-19 subjects in both morphologically identified bronchioles and microcysts, and MUC5B accumulated in damaged alveolar spaces. SARS-CoV-2-infected HBE cultures exhibited peak titers 3 days post inoculation, whereas induction of MUC5B/MUC5AC peaked 7-14 days post inoculation. SARS-CoV-2 infection of HBE cultures induced expression of EGFR ligands and inflammatory cytokines (e.g., IL-1α/β) associated with mucin gene regulation. Inhibiting EGFR/IL-1R pathways, or dexamethasone administration, reduced SARS-CoV-2-induced mucin expression. CONCLUSIONS: SARS-CoV-2 infection is associated with a high prevalence of distal airspace mucus accumulation and increased MUC5B expression in COVID-19 autopsy lungs. HBE culture studies identified roles for EGFR and IL-1R signaling in mucin gene regulation post SARS-CoV-2 infection. These data suggest that time-sensitive mucolytic agents, specific pathway inhibitors, or corticosteroid administration may be therapeutic for COVID-19 lung disease. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

BACKGROUND: Renal impairment is a predictor of coronavirus disease (COVID-19) severity. No studies have compared COVID-19 outcomes in patients with chronic kidney disease (CKD) and patients with impaired renal function without a prior diagnosis of CKD. This study aimed to identify the impact of pre-existing impaired renal function without CKD on COVID-19 outcomes. METHODS: This retrospective study included 3,637 patients with COVID-19 classified into three groups by CKD history and estimated glomerular filtration rate (eGFR) on referral: Group 1 (n = 2,460), normal renal function without a CKD history; Group 2 (n = 905), impaired renal function without a CKD history; and Group 3 (n = 272), history of CKD. We compared the clinical characteristics of these groups and assessed the effect of CKD and impaired renal function on critical outcomes (requirement for respiratory support with high-flow oxygen devices, invasive mechanical ventilation, or extracorporeal membrane oxygen, and death during hospitalization) using multivariable logistic regression. RESULTS: The prevalence of comorbidities (hypertension, diabetes, and cardiovascular disease) and incidence of inflammatory responses (white blood counts, and C-reactive protein, procalcitonin, and D-dimer levels) and complications (bacterial infection and heart failure) were higher in Groups 2 and 3 than that in Group 1. The incidence of critical outcomes was 10.8%, 17.7%, and 26.8% in Groups 1, 2, and 3, respectively. The mortality rate and the rate of requiring IMV support was lowest in Group 1 and highest in Group 3. Compared with Group 1, the risk of critical outcomes was higher in Group 2 (adjusted odds ratio [aOR]: 1.32, 95% confidence interval [CI]: 1.03-1.70, P = 0.030) and Group 3 (aOR: 1.94, 95% CI: 1.36-2.78, P < 0.001). Additionally, the eGFR was significantly associated with critical outcomes in Groups 2 (odds ratio [OR]: 2.89, 95% CI: 1.64-4.98, P < 0.001) and 3 (OR: 1.87, 95% CI: 1.08-3.23, P = 0.025) only. CONCLUSIONS: Clinicians should consider pre-existing CKD and impaired renal function at the time of COVID-19 diagnosis for the management of COVID-19.

The effect of preexisting hypertension on coronavirus disease 2019 (COVID-19) prognosis remains controversial. Additionally, no studies have compared the association between blood pressure (BP) indices on admission and COVID-19 outcomes using preexisting hypertension status. Therefore, this study aimed to investigate the association between preexisting hypertension and COVID-19 outcomes in Japanese patients with COVID-19 and assess the impact of BP indices on admission on clinical outcomes in patients with and without preexisting hypertension. Preexisting hypertension presence was confirmed based on the patient's clinical history. Critical outcomes were defined as high-flow oxygen use, non-invasive and invasive positive-pressure ventilation, extracorporeal membrane oxygenation, or death during hospitalization. Preexisting hypertension was observed in 64.6% of the patients. Multivariable logistic regression analysis of severe COVID-19 risk factors indicated that preexisting hypertension was independently associated with critical outcomes [adjusted odds ratio (OR): 1.35; 95% confidence interval (CI): 1.05-1.73]. Low or high BP and high pulse pressure on admission were associated with critical outcomes in patients without preexisting hypertension [OR for systolic BP < 100 mmHg: 2.13, 95% CI: 1.21-3.75; OR for high BP stage 2 (160-179 systolic and/or 100-109 mmHg diastolic BP): 2.13, 95% CI: 1.27-3.58; OR for pulse pressure ≥60 mmHg: 1.68, 95% CI: 1.14-2.48]. Preexisting hypertension is a risk factor for critical outcomes in Japanese patients with COVID-19. BP indices are useful biomarkers for predicting COVID-19 outcomes, particularly in patients without preexisting hypertension. Thus, hypertension history, systolic BP, and pulse pressure should be assessed to predict severe COVID-19 outcomes.

BACKGROUND: To determine the effectiveness of baricitinib in patients with coronavirus disease 2019 (COVID-19), investigate whether baricitinib prevents the need for invasive mechanical ventilation and identify patient subgroups that would benefit from baricitinib. METHODS: This observational matched-cohort study was conducted by the Japan COVID-19 Task Force, a nationwide multicenter consortium. Patients with COVID-19 aged ≥18 years were identified from 70 hospitals in Japan. Among patients with confirmed COVID-19 from February 2020 to September 2021, those receiving baricitinib were propensity-score matched with controls. RESULTS: Among 3309 patients, 144 propensity score-matched pairs were identified. Thirteen (9.0%) patients in the baricitinib group and 27 (18.8%) in the control group required invasive mechanical ventilation during the disease course (odds ratio, 0.43). Although the baricitinib group had more severe disease, there were no significant differences in the intensive care unit admission rates (odds ratio, 1.16) and mortality rates (odds ratio, 0.74) between groups. In subgroup analyses, baricitinib was associated with a significant reduction in the need for invasive mechanical ventilation in patients requiring oxygen support (odds ratio, 0.28), with rapid shadow spread on chest radiography (odds ratio, 0.11), or treated with remdesivir (odds ratio, 0.27), systemic corticosteroids (odds ratio, 0.31), or anticoagulants (odds ratio, 0.17). CONCLUSIONS: Baricitinib is effective at preventing the need for invasive mechanical ventilation in patients with COVID-19.

BACKGROUND: Interleukin-6 (IL-6) is elevated in SARS-CoV-2 infection. IL-6 regulates acute-phase proteins, such as alpha-1 antitrypsin (AAT), a key lung anti-protease. We investigated the protease-anti-protease balance in the circulation and pulmonary compartments in SARS-CoV-2 acute respiratory distress syndrome (ARDS) compared to non-SARS-CoV-2 ARDS (nsARDS) and the effects of tocilizumab (IL-6 receptor antagonist) on anti-protease defence in SARS-CoV-2 infection. METHODS: Levels and activity of AAT and neutrophil elastase (NE) were measured in plasma, airway tissue and tracheal secretions (TA) of people with SARS-CoV-2 ARDS or nsARDS. AAT and IL-6 levels were evaluated in people with moderate SARS-CoV-2 infection who received standard of care +/- tocilizumab. FINDINGS: AAT plasma levels doubled in SARS-CoV-2 ARDS. In lung parenchyma AAT levels were increased, as was the percentage of neutrophils involved in NET formation. A protease-anti-protease imbalance was detected in TA with active NE and no active AAT. The airway anti-protease, secretory leukoprotease inhibitor was decreased in SARS-CoV-2-infected lungs and cleaved in TA. In nsARDS, plasma AAT levels were elevated but TA samples had less AAT cleavage, with no detectable active NE in most samples. Induction of AAT in ARDS occurred mainly through IL-6. Tocilizumab down-regulated AAT during SARS-CoV-2 infection. INTERPRETATION: There is a protease-anti-protease imbalance in the airways of SARS-CoV-2-ARDS patients. This imbalance is a target for anti-protease therapy. FUNDING: NIH Serological Sciences Network, National Heart, Lung, and Blood Institute and National Institute of Diabetes and Digestive and Kidney Diseases.

Background: Pulmonary resection along with multiple antimicrobial therapy has produced favorable outcomes at a few centers. However, little is known regarding the risk factors for long-term survival and microbiological recurrence after pulmonary resection for nontuberculous mycobacterial pulmonary disease (NTMPD). We evaluated the long-term outcomes of pulmonary resection, including microbiological recurrence and survival. Methods: This retrospective cohort study included 125 patients (median age, 60 years) with NTMPD treated by pulmonary resection at two referral centers between January 1994 and August 2015. Results: Postoperative complications occurred in 27 patients (22%). The complication rate after pneumonectomy was significantly higher than those after other types of pulmonary resection (odds ratio, 4.1; 95% confidence interval [CI], 1.6-10.3; P = .005). The median follow-up period was 7.1 years. While 19 patients experienced microbiological recurrence, 26 died. Multivariate analysis revealed pneumonectomy (adjusted hazard ratio [aHR], 0.12; 95% CI, .007-.66; P = .0098) and cavitary lesions after surgery (aHR, 6.73; 95% CI, 1.68-22.7; P = .0095) to be predictors of microbiological recurrence and old age (aHR, 1.06; 95% CI, 1.01-1.13; P = .016), low body mass index (BMI; aHR for every 1-kg/m2 increase, 0.72; 95% CI, .60-.85; P < .0001), pneumonectomy (aHR, 4.38; 95% CI, 1.78-11.3; P = .014), and remnant cavitary lesions (aHR, 3.53; 95% CI, 1.35-9.57; P = .011) to be predictors of poor prognosis. Conclusions: Patients who could benefit from pulmonary resection should be carefully selected considering age, BMI, remnant lesions after surgery, and type of pulmonary resection.

BACKGROUND: The risk factors for Mycobacterium avium complex lung disease (MAC-LD) are not well known. We hypothesized that low serum estradiol (E2) levels are related to MAC-LD as most patients with MAC-LD are postmenopausal women. METHODS: This cross-sectional study compared patients with MAC-LD and healthy controls. Study subjects were postmenopausal women aged 65 years or younger. Serum testosterone, dehydroepiandrosterone sulfate (DHEA-S), and E2 levels were measured and categorized as high or low based on median levels. We performed multivariate analysis, receiver operating characteristic (ROC) curve analysis, and age- and body mass index (BMI)-matched subgroup analysis to evaluate the association between low serum E2 levels and MAC-LD. Additionally, using blood samples obtained for other clinical studies, the levels of sex steroid hormones were compared between age- and BMI-matched MAC-LD and bronchiectasis female patients without non-tuberculosis mycobacterial infections (non-NTM BE). RESULTS: Forty-two patients with MAC-LD and 91 healthy controls were included. The median E2 (2.20 pg/mL vs. 15.0 pg/mL, p < 0.001), testosterone (0.230 ng/L vs. 0.250 ng/L, p = 0.005), and DHEA-S (82.5 μg/dL vs. 114.0 μg/dL, p < 0.001) levels were lower in the MAC-LD group than in the control group. Multivariate analysis revealed that low serum E2 (adjusted odds ratio = 34.62, 95% confidence interval = 6.02-199.14) was independently related to MAC-LD, whereas low DHEA-S and testosterone were not. ROC analysis illustrated a strong relationship between low serum E2 levels and MAC-LD (area under the curve = 0.947, 95% confidence interval = 0.899-0.995). Even the age- and BMI-matched subgroup analysis of 17 MAC-LD patients and 17 healthy controls showed lower serum E2 in MAC-LD patients than in healthy controls. Additionally, serum E2 levels of 20 MAC-LD patients were lower than plasma E2 levels of 11 matched non-NTM BE patients (1.79 pg/mL vs. 11.0 pg/mL, p < 0.001). CONCLUSIONS: Low serum E2 levels were strongly related to MAC-LD in postmenopausal women.

Cytomegalovirus superinfection is associated with a poor prognosis in non-HIV Pneumocystis pneumonia (PCP) and can cause deterioration of PCP not only simultaneously but also after initiating PCP treatment. Cytomegalovirus pneumonia should be considered in cases with deterioration after initiating PCP treatment; multiple nodular lesions are useful findings for the diagnosis.

BACKGROUND: Presence of Mycobacterium fortuitum in respiratory tracts usually indicates mere colonization or transient infection, whereas true pulmonary infection occurs in patients with gastroesophageal disease. However, little is known about the diagnostic indications for true M. fortuitum pulmonary infection and the natural history of the disease. CASE PRESENTATION: A 59-year-old man was referred to our hospital for treatment against M. fortuitum pulmonary infection. Fifteen years before the referral, he underwent total gastrectomy, after which he experienced esophageal reflux symptoms. After the referral, the patient was closely monitored without antimicrobial therapy because of mild symptoms and no pathological evidence of M. fortuitum pulmonary infection. During the observation, chest imaging showed migratory infiltrates. Two years after the referral, his lung biopsy specimen revealed foamy macrophages and multinucleated giant cells, indicating lipoid pneumonia. However, he was continually monitored without any treatment because there was no evidence of nontuberculous mycobacterial infection. Four years after the referral, he developed refractory pneumonia despite receiving adequate antibiotic therapy. After confirmation of granulomatous lesions, multiple antimicrobial therapy for M. fortuitum resulted in a remarkable improvement with no exacerbation for over 5 years. Random amplified polymorphic DNA polymerase chain reaction analysis revealed identical M. fortuitum strains in seven isolates from six sputum and one intestinal fluid specimens obtained during the course of the disease. CONCLUSIONS: We have described a patient with M. fortuitum pulmonary infection who presented with migratory infiltrates. The pathological evidence and microbiological analysis suggested that M. fortuitum pulmonary infection was associated with lipoid pneumonia and chronic exposure to gastrointestinal fluid. Therefore, physicians should carefully monitor patients with M. fortuitum detected from lower respiratory tract specimens and consider antimicrobial therapy for M. fortuitum infection when the patient does not respond to adequate antibiotic therapy against common pneumonia pathogens.