堀口 智也

BACKGROUND: No comprehensive analysis of the pulmonary sequelae of coronavirus disease 2019 (COVID-19) in Japan based on respiratory function tests and chest computed tomography (CT) has been reported. We evaluated post-COVID-19 conditions, especially focusing on pulmonary sequelae assessed by pulmonary function tests and chest CT. METHODS: For this prospective cohort study, we enrolled 1069 patients who presented pneumonia at the time of admission in 55 hospitals from February 2020 to September 2021. Disease severity was classified as moderateⅠ, moderate II, and severe, defined primarily according to the degree of respiratory failure. The data on post-COVID-19 conditions over 12 months, pulmonary function, and chest CT findings at 3 months were evaluated in this study. Additionally, the impact of COVID-19 severity on pulmonary sequelae, such as impaired diffusion capacity, restrictive pattern, and CT abnormalities, was also evaluated. RESULTS: The most frequently reported post-COVID-19 conditions at 3 months after COVID-19 were muscle weakness, dyspnea, and fatigue (48.4%, 29.0%, and 24.7%, respectively). The frequency of symptoms gradually decreased over subsequent months. In pulmonary function tests at 3 months, the incidence of impaired diffusion capacity and restrictive pattern increased depending on disease severity. There also were differences in the presence of chest CT abnormalities at the 3 months, which was markedly correlated with the severity. CONCLUSION: We reported a comprehensive analysis of post-COVID-19 condition, pulmonary function, and chest CT abnormalities in Japanese patients with COVID-19. The findings of this study will serve as valuable reference data for future post-COVID-19 condition research in Japan.

INTRODUCTION: Increasing numbers of cases of mild asymptomatic pulmonary alveolar proteinosis (PAP) are being reported with the recent increase in chest computed tomography (CT). Bronchoscopic diagnosis of mild PAP is challenging because of the patchy distribution of lesions, which makes it difficult to obtain sufficient biopsy samples. Additionally, the pathological findings of mild PAP, particularly those that differ from severe PAP, have not been fully elucidated. This study aimed to clarify the pathological findings of mild PAP and the usefulness of optical biopsy using probe-based confocal laser endomicroscopy (pCLE). METHODS: We performed bronchoscopic optical biopsy using pCLE and tissue biopsy in five consecutive patients with PAP (three with mild PAP and two with severe PAP). We compared the pCLE images of mild PAP with those of severe PAP by integrating clinical findings, tissue pathology, and chest computed tomography images. RESULTS: pCLE images of PAP showed giant cells with strong fluorescence, amorphous substances, and thin alveolar walls. Images of affected lesions in mild PAP were equivalent to those obtained in arbitrary lung lesions in severe cases. All three patients with mild PAP spontaneously improved or remained stable after ≥3 years of follow-up. Serum autoantibodies to granulocyte-macrophage colony-stimulating factor were detected in all five cases. CONCLUSION: Optical biopsy using pCLE can yield specific diagnostic findings, even in patients with mild PAP. pCLE images of affected areas in mild and severe PAP showed similar findings, indicating that the dysfunction level of pathogenic alveolar macrophages in affected areas is similar between both disease intensities.

BACKGROUND: Bronchial thermoplasty (BT) is a recently developed non-pharmacological therapy for refractory bronchial asthma. Although increasing evidence has suggested that BT is effective for various phenotypes of severe asthma, its safety and efficacy in patients with severe irreversible impaired lung function are unclear. OBJECTIVES: To assess the efficacy and safety of BT in patients with refractory asthma, including patients with a severely impaired forced expiratory volume in 1 second (FEV1). DESIGN: This was a single-center, retrospective, observational cohort study. METHODS: We retrospectively reviewed the medical records of 15 patients with refractory asthma (Global Initiative for Asthma step 4 or 5), including patients with severely impaired airflow limitation (% predicted pre-bronchodilator FEV1 <60%), who had undergone BT between June 2016 and January 2022. We analyzed the efficacy (change in asthma symptoms, exacerbation rate, pulmonary function, asthma medication, and serum inflammatory chemokine/cytokines before and after BT) and complications in all patients. We compared these data between patients with severe obstructive lung dysfunction [group 1(G1)] and patients with FEV1 ⩾ 60% [group 2 (G2)]. RESULTS: Six patients were in G1 and nine were in G2. Clinical characteristics, T2 inflammation, and concurrent treatment were equivalent in both groups. BT significantly improved asthma-related symptoms (measured using the Asthma Control Test and Asthma Quality of Life Questionnaire scores) in both groups. FEV1 was significantly improved in G1 but not in G2. Four patients in G2, but none in G1, experienced asthma exacerbation requiring additional systemic corticosteroids (including two requiring prolonged hospitalization) after BT. Long-term responders (patients who reduced systemic or inhaled corticosteroid without newly adding biologics in a follow-up > 2 years) of BT were identified in G1 and G2 (n = 2, 33.3% and n = 4, 44.4%, respectively). CONCLUSION: BT in patients with refractory asthma and severe airflow limitation is equally safe and efficacious as that in patients with moderate airflow limitation.

Syphilis can cause a wide range of systemic manifestations, such as papular rash, malaise, weight loss, muscle aches, generalized lymphadenopathy, and meningitis. However, pulmonary involvement in patients with secondary syphilis is thought to be relatively rare. Moreover, bone involvement in patients with secondary syphilis is also considered rare, and only a few cases of involvement of lung and bone in such patients have been reported. In this paper, we report a case of secondary syphilis with pulmonary involvement in the form of multiple nodules with low attenuation areas, lymphadenopathy and multiple bone lesions detected on computed tomography and 18F fluorodeoxyglucose-positron emission tomography/computed tomography.

Secondary fungal infections are a critical problem that accompany immunosuppressive therapy for severe coronavirus disease 2019 (COVID-19). We report a fatal case of COVID-19 with disseminated mucormycosis diagnosed during autopsy. A 58-year-old man with diabetes was hospitalized for severe COVID-19 and treated with remdesivir, systemic steroids and tocilizumab. Following treatment, he was provided extracorporeal membrane oxygenation support. However, he died of multiple organ failure accompanied by pulmonary and kidney infarction, as revealed by computed tomography. Autopsy revealed that the infarction was caused by thromboangiitis due to mucormycosis in the brain, lungs, heart, liver and kidneys. Therefore, the diagnosis of disseminated mucormycosis was established. Disseminated mucormycosis is a rare complication of COVID-19. Although its early diagnosis is difficult, the disease progresses rapidly. Hence, we propose that immunosuppressive treatment for COVID-19 should be administered with caution considering the risk of developing severe opportunistic infections, such as mucormycosis.