Published papers

BACKGROUND: Pulmonary nocardiosis frequently develops as an opportunistic infection in cell-mediated immunosuppressive patients, and sometimes requires differentiation from pulmonary malignancy. Ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) is a neoplastic disorder which leads to impaired cell-mediated immunity, and is commonly associated with small cell lung cancer (SCLC). Because pulmonary infection and causative malignancy can appear as pulmonary lesions with EAS, differentiation of these diseases remains a critical issue for physicians. CASE PRESENTATION: A 52-year-old woman with progressive lower limb paralysis and general fatigue was referred to us. She had been diagnosed with olfactory neuroblastoma (ONB) and treated with surgery and radiation therapy 10 years before the referral and had required stereotactic radiosurgery and chemotherapy 4 years later for a relapse of the ONB. On referral, she presented with Cushing's syndrome with elevated cortisol and ACTH levels. Potassium supplement improved her symptoms; however, a month later, she was urgently hospitalized due to acute pleuritic chest pain on inspiration. Chest computed tomography revealed left lower lobular consolidations and a contralateral nodule in the right middle lobe. The clinical history and laboratory work-up suggested that her Cushing's syndrome had most likely arisen from EAS. Additionally, the lungs were suspected as the ACTH source due to high levels of progastrin-releasing peptide and progressive pulmonary consolidation with a contralateral nodule, suggesting SCLC. However, histological examination from bronchoscopy revealed no evidence of malignancy, and Nocardia cyriacigeorgica was isolated from bronchoalveolar lavage fluid. Sulfamethoxazole/trimethoprim improved her pulmonary lesions. Somatostatin receptor scintigraphy revealed strong tracer uptake in the ONB lesions, indicating that the origin of the EAS was the olfactory tumor. However, histological examination of ONB specimens resected 10 years earlier showed no intracytoplasmic immunopositivity for ACTH. CONCLUSIONS: We highlight a rare case of pulmonary nocardiosis, which was associated with EAS mimicking SCLC, and was related to ONB transformation. Nocardiosis has to be considered even though anamnestic, clinical, and radiological aspects suggest the presence of metastasis. Additionally, physicians should carefully monitor patients with ONB for the development of Cushing's symptoms because the tumor can transform into an ACTH-producing form, even after long-term follow-up.

BACKGROUND AND OBJECTIVE: No reports exist regarding skeletal muscle involvement in patients with Mycobacterium avium complex lung disease (MAC-LD). The cross-sectional area of the erector spinae muscles (ESMCSA) reflects physical activity and can be assessed by computed tomography (CT). We investigated the relationship between ESMCSA and physiological parameters and prognosis in MAC-LD patients. MATERIAL AND METHODS: In this prospective observational study, the ESMCSA was measured on single-slice axial CT images. MAC-LD patients and sex- and age-matched controls (non-MAC-LD participants) were evaluated. We evaluated the relationship between the ESMCSA and physiological parameters and prognosis. RESULTS: A total of 260 patients (209 female; median age, 69 years; 190 with nodular/bronchiectatic disease; 74 with cavitary lesions) were enrolled. The ESMCSA was not different between MAC-LD patients and controls. In MAC-LD patients, the ESMCSA was significantly associated with age, body mass index (BMI), pulmonary function, CT severity, and health-related quality of life (HRQL). Multivariate Cox proportional hazards analyses revealed that an ESMCSA < -1 standard derivation (hazards ratio [HR], 2.76; P = 0.047) was significantly associated with all-cause mortality, along with BMI < 18.5 kg/m2 (HR, 3.67; P = 0.02) and presence of cavitary lesions (HR, 5.84; P = 0.001). However, the ESMCSA was not significantly associated with all-cause mortality when current treatment status, % predicted functional vital capacity, and forced expiratory volume in 1 s were added to the analyses. CONCLUSIONS: Although the prognostic impact was limited, ESMCSA was significantly associated with HRQL and prognostic physiological parameters, such as BMI and pulmonary function.

BACKGROUND: Coexistence of aspergilloma and allergic bronchopulmonary aspergillosis (ABPA) has rarely been reported. Although the treatment for ABPA includes administration of corticosteroids and antifungal agents, little is known about the treatment for coexisting aspergilloma and ABPA. Furthermore, the impact of surgical resection for aspergilloma on ABPA is not fully understood. Here, we present an interesting case of recurrent ABPA with long-term follow-up after surgical resection of aspergilloma. CASE PRESENTATION: A 53-year-old man with a medical history of tuberculosis was referred to our hospital with cough and dyspnea. Imaging revealed multiple cavitary lesions in the right upper lobe of the lung, with a fungus ball and mucoid impaction. The eosinophil count, total serum immunoglobulin E (IgE), and Aspergillus-specific IgE levels were elevated. Specimens collected on bronchoscopy revealed fungal filaments compatible with Aspergillus species. Based on these findings, a diagnosis of ABPA with concomitant aspergilloma was made. Although treatment with corticosteroids and antifungal agents was administered, the patient's respiratory symptoms persisted. Therefore, he underwent lobectomy of the right upper lobe, which resulted in a stable condition without the need for medication. Twenty-three months after discontinuation of medical treatment, his respiratory symptoms gradually worsened with a recurrence of elevated eosinophil count and total serum IgE. Imaging revealed recurrent bronchiectasis and cavities with mucoid impaction in the right lower lobe, suggesting relapse of aspergilloma and ABPA. Corticosteroids and antifungal agents were re-administered; aspergilloma improved slightly over a 5-year period, and ABPA remained well controlled with low-dose prednisolone (5 mg/day). CONCLUSIONS: We describe the long-term follow-up outcomes of a patient with concomitant ABPA and aspergilloma, who underwent surgical resection for aspergilloma. Physicians should carefully monitor patients with coexisting ABPA and aspergilloma, as the condition may relapse after remission, even despite surgical resection for aspergilloma. Additionally, surgical resection for aspergilloma could result in resolution of ABPA.

Roving eye movements are the sign of cortical dysfunction not involving the brainstem. This finding is useful in the differential diagnosis of impaired consciousness and indicates cerebral damage in patients with hypoglycemic coma.

The mode of acquisition and causes for the variable clinical spectrum of coronavirus disease 2019 (COVID-19) remain unknown. We utilized a reverse genetics system to generate a GFP reporter virus to explore severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pathogenesis and a luciferase reporter virus to demonstrate sera collected from SARS and COVID-19 patients exhibited limited cross-CoV neutralization. High-sensitivity RNA in situ mapping revealed the highest angiotensin-converting enzyme 2 (ACE2) expression in the nose with decreasing expression throughout the lower respiratory tract, paralleled by a striking gradient of SARS-CoV-2 infection in proximal (high) versus distal (low) pulmonary epithelial cultures. COVID-19 autopsied lung studies identified focal disease and, congruent with culture data, SARS-CoV-2-infected ciliated and type 2 pneumocyte cells in airway and alveolar regions, respectively. These findings highlight the nasal susceptibility to SARS-CoV-2 with likely subsequent aspiration-mediated virus seeding to the lung in SARS-CoV-2 pathogenesis. These reagents provide a foundation for investigations into virus-host interactions in protective immunity, host susceptibility, and virus pathogenesis.

Background: Sitafloxacin (STFX) exhibits potent activity against Mycobacterium avium complex (MAC) in both in vitro and in vivo experiments. However, limited data are available for the clinical efficacy and adverse effects of STFX and the susceptibility of refractory MAC lung disease (MAC-LD) to the drug. Therefore, this study was aimed at evaluating the clinical efficacy and safety of an STFX-containing regimen for the treatment of refractory MAC-LD. Methods: We retrospectively evaluated treatment outcomes of 31 patients with refractory MAC-LD, who received an STFX-containing regimen for ≥4 weeks between January 2010 and July 2017. Refractory MAC-LD was defined as persistent positive sputum cultures for >6 months of macrolide-based standard therapy. Results: Clarithromycin resistance (minimum inhibitory concentration [MIC] ≥32 μg/mL) was identified in 15 patients (48%). Twelve months after receiving the STFX-containing regimen, 26% and 19% of patients showed symptomatic and radiological responses, respectively. Although STFX-associated adverse effects were noted in 9 patients, their severity was grade 1 (National Cancer Institute Common Terminology Criteria); only 1 patient discontinued STFX because of suspected gastrointestinal disturbance. Negative sputum culture conversion was achieved in 7 patients (23%). Both univariate and multivariate logistic regression analyses revealed that surgery, low STFX MIC (≤1 μg/mL), and macrolide resistance were significant predictors of negative sputum culture conversion. Conclusions: Our results demonstrate that STFX may be effective in one-fourth of patients with refractory MAC-LD. Prospective larger studies that include the analyses of MAC are needed to determine the clinical efficacy of STFX against refractory MAC-LD.

Small cell lung cancer (SCLC) causes paraneoplastic syndromes, such as diabetes mellitus, by eliciting the expression of various antibodies including anti-glutamate decarboxylase (GAD) antibody. A 62-year-old woman presented to our hospital with a 1-week history of progressive dyspnea and difficulty in walking. Computed tomography showed a tumor obstructing the left bronchus and obstructive lung abscesses with pleural effusions. A biopsy during bronchoscopy revealed SCLC, and the clinical stage was ultimately determined to be IIIB. SCLC was complicated by diabetes mellitus with high titers of serum anti-GAD antibody. An immunohistochemical analysis showed GAD expression in the cancer cells, which is a novel finding.

Sphingolipids play a pivotal role in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, little is known about the precise roles of sphingosine-1-phosphate (S1P), a bioactive sphingolipid metabolite, and its receptor modulation in COPD. In this study, we demonstrated that the S1P receptor modulator ONO-4641 induced the expansion of lung CD11b+Gr-1+ cells and lymphocytopenia in naive mice. ONO-4641-expanded CD11b+Gr-1+ cells showed higher arginase-1 activity, decreased T cell proliferation, and lower IFN-γ production in CD3+ T cells, similar to the features of myeloid-derived suppressor cells. ONO-4641 treatment decreased airspace enlargement in elastase-induced and cigarette smoke-induced emphysema models and attenuated emphysema exacerbation induced by post-elastase pneumococcal infection, which was also associated with an increased number of lung CD11b+Gr-1+ cells. Adoptive transfer of ONO-4641-expanded CD11b+Gr-1+ cells protected against elastase-induced emphysema. Lymphocytopenia observed in these models likely contributed to beneficial ONO-4641 effects. Thus, ONO-4641 attenuated murine pulmonary emphysema by expanding lung CD11b+Gr-1+ cell populations and inducing lymphocytopenia. The S1P receptor might be a promising target for strategies aimed at ameliorating pulmonary emphysema progression.

RATIONALE: Hyper IgE syndrome (STAT3-HIES), also known as Job's syndrome, is a rare immunodeficiency disease typically caused by dominant-negative STAT3 mutations. STAT3-HIES is characterized by chronic pulmonary infection and inflammation, suggesting impaired innate host defense. OBJECTIVES: To identify airway epithelial host defense defects caused by STAT3 mutations that, together with immune dysfunction, contribute to recurrent pulmonary infections in STAT3-HIES. METHODS: STAT3-HIES sputum was analyzed for biochemical and biophysical properties. STAT3-HIES excised lungs were harvested for histology; and bronchial brush samples were collected for RNA sequencing and in vitro culture. A STAT3-HIES-specific R382W mutation, expressed via lentivirus, and STAT3 knockout (CRISPR/Cas9), were studied in normal human bronchial epithelial cells under basal or inflammatory (IL1β)-stimulated conditions. Effects of STAT3 deficiency on transcriptomics, epithelial ion channel, secretory, antimicrobial, and ciliary functions were assessed. MEASUREMENTS AND MAIN RESULTS: STAT3-HIES sputum showed increased mucus concentration and viscoelasticity. STAT3-HIES excised lungs exhibited mucus obstruction and elevated IL1β expression. STAT3 mutations reduced CFTR mRNA and protein levels, impaired CFTR-dependent fluid and mucin secretion, suppressed antimicrobial peptide, cytokine, and chemokine expression, and acidified airway surface liquid at baseline and post-IL1β exposure. Notably, mutant STAT3 suppressed IL1R1 expression. Furthermore, STAT3 mutations impaired multiciliogenesis by blocking commitment to ciliated cell lineages through inhibition of HES6, leading to defective mucociliary transport. Administration of a γ-secretase inhibitor restored HES6 expression, improved ciliogenesis in STAT3 R382W mutant cells. CONCLUSIONS: STAT3 dysfunction leads to multi-component defects in airway epithelial innate defense, which, in conjunction with immune deficiency, contributes to chronic pulmonary infection in STAT3-HIES.

Asakura T, Higuchi A, Mori N, QJM : monthly journal of the Association of Physicians, 2016

Intramedullary spinal cord metastases (ISCMs) of non-small cell lung cancer (NSCLC) constitute a serious if infrequent complication, characterised by rapid progression of neurological deficits, with poor prognosis. We describe a 52-year-old man with ISCMs secondary to lung adenocarcinoma who acquired the T790M mutation of the epidermal growth factor receptor (EGFR) after previous use of a first-generation EGFR tyrosine kinase inhibitor (TKI); he was successfully treated with osimertinib. This is the first report of the use of osimertinib in ISCMs: due to its high central nervous system activity, osimertinib could be useful for treating ISCMs secondary to NSCLC in patients who exhibit the T790M mutation.

Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI)-induced interstitial lung disease (ILD) may be a life-threatening condition that may develop during treatment of lung cancer patients harboring EGFR mutations. We herein present the case of a 41-year-old female patient diagnosed with lung adenocarcinoma with an EGFR mutation (exon 19 deletion). The patient was treated with gefitinib followed by erlotinib and developed ILD induced by both EGFR-TKIs; furthermore, the patient acquired resistance to EGFR-TKI treatment. A repeat biopsy revealed a T790M mutation, which is associated with resistance to first-generation EGFR-TKIs, along with an exon 19 deletion identified by cytology of the pleural fluid. Treatment with afatinib and prednisolone resulted in tumor shrinkage, without worsening of the ILD. The present case demonstrated that combination treatment with afatinib and a glucocorticoid may be effective for the treatment of lung cancer patients who develop EGFR-TKI-induced ILD.

RATIONAL: The efficacy of nintedanib, a multitarget receptor tyrosine kinase inhibitor, has been demonstrated in recent randomized controlled trials involving patients with idiopathic pulmonary fibrosis (IPF). However, accelerated disease progression after nintedanib discontinuation has never been reported. PATIENT CONCERNS: We report 2 cases involving patients with a history of IPF who presented with respiratory deterioration at 3 weeks after the discontinuation of nintedanib therapy for IPF. Neither patient fulfilled the definition of "acute exacerbation of IPF" on unilateral computed tomography. DIAGNOSES: Accelerated disease progression after the discontinuation of nintedanib therapy for IPF. INTERVENTIONS: One patient received steroid therapy. The other patient refused to undergo steroid therapy. OUTCOMES: The first patient showed that the affected lobe exhibited volume loss with traction bronchiectasis after receiving steroid therapy, and succumbed to pneumothorax after 3 months. The other patient was transferred to another hospital because of a decline in his general condition. LESSONS: To our knowledge, this report is the first to document accelerated disease progression after the discontinuation of nintedanib therapy for IPF. Although the accurate mechanism remains unclear, the effects of nintedanib against vascular endothelial growth factor and platelet-derived growth factor receptor may play a role. Our findings suggest that physicians should carefully monitor patients with IPF after nintedanib discontinuation.

BACKGROUND: In multidrug regimens, including an intravenous aminoglycoside (e.g. amikacin [AMK]) is recommended for difficult-to-treat non-tuberculous mycobacterial (NTM) lung diseases. We aimed to evaluate the efficacy, safety, and feasibility of inhaled AMK therapy in patients with difficult-to-treat NTM lung diseases in a retrospective chart review. METHODS: The study population consisted of patients with NTM lung diseases who received combination therapy, including inhaled AMK therapy, at Keio University Hospital (Tokyo, Japan), from January 2014 through May 2016. A total of 26 cases, consisting of 23 Mycobacterium avium complex (MAC) and three Mycobacterium abscessus complex (MABC) infections cases, were included in this study. The efficacy, safety, and feasibility of inhaled AMK therapy were retrospectively investigated. The Research Ethics Committee of Keio University Hospital approved this study, and informed consent was obtained from all patients. RESULTS: All 26 patients were culture-positive at enrolment. Twenty-three of the 26 patients (88.5%), including 21/23 MAC patients (91.3%) and 2/3 MABC patients (66.7%), were administered inhaled AMK therapy for >3 months. The proportion of patients who had clinical symptoms, including, cough and sputum, declined after inhalation AMK therapy. Ten of the 23 patients (43.5%) who received AMK inhalation, including 8/21 MAC (38.1%) and 2/2 MABC patients (100%), showed sputum conversion, defined as at least three consecutive negative sputum cultures. Seven of the 23 patients, including, 5/21 MAC and 2/2 MABC patients, showed improvements in high-resolution computed tomography imaging of the chest. In addition, the serum AMK trough levels before the second inhalation were <1.2 μg/mL in all 26 patients, with no occurrence of severe adverse events, such as renal toxicity. One patient (3.8%) experienced auditory toxicity, in the form of tinnitus. However, this symptom was reversible, after temporary interruption of AMK, the patient was able to safely resume the therapy. CONCLUSIONS: Inhaled AMK therapy is an effective and feasible therapy for difficult-to-treat NTM lung disease.