Among 25 patients with refractory Mycobacterium avium complex pulmonary disease treated with amikacin liposome inhalation suspension (ALIS), 9 achieved culture conversion. Culture conversion was associated with the absence of cavitary lesion, higher body mass index, lower inflammatory marker levels, and lower baseline Chronic Airways Assessment Test (CAAT) scores. Among the 20 patients evaluable for CAAT, 5 achieved culture conversion alone, 5 achieved CAAT improvement alone, and 2 achieved both, such that 12 patients demonstrated improvement in at least one of the two outcome measures. However, culture conversion and improvement in CAAT scores were discordant in many cases. These findings suggest that the efficacy of ALIS should be assessed multidimensionally by incorporating patient-reported outcomes.

A 45-year-old man with no underlying diseases developed dyspnea 6 days before presenting to our hospital. He initially visited a local physician, who suspected acute pulmonary thromboembolism, and referred him to our hospital. Type I respiratory failure, pulmonary hypertension, thrombocytopenia, and elevated serum lactate dehydrogenase suggested pulmonary tumor embolism. Pulmonary artery wedge aspiration cytology revealed atypical cells. Gastroscopy showed histological findings compatible with adenocarcinoma. Chemotherapy was initiated; however, the patient died due to progressive respiratory failure.

A 70-year-old man with a history of bronchial asthma presented with intractable wheezing. Chest CT demonstrated diffuse thickening of the tracheal and main bronchial walls with preservation of the membranous portion, suggesting relapsing polychondritis (RP). Bronchoscopic findings were consistent with airway inflammation, and a surgical tracheal cartilage biopsy enabled a definitive diagnosis. Airway-limited RP is often difficult to diagnose promptly because auricular or nasal involvement is absent. In this case, identification during the inflammatory phase allowed timely initiation of corticosteroid therapy, which led to rapid clinical improvement and obviated the need for interventional airway procedures. Careful assessment with imaging, endoscopy, and early tissue sampling is important for establishing the diagnosis of airway-limited RP and may contribute to improved outcomes.

A 65-year-old man had been receiving nivolumab for esophageal cancer since Year X−2 and maintained tumor shrinkage. In July of Year X, he presented a cough, and chest CT revealed an infiltrative shadow in the right lower lobe. His symptoms did not improve, and a chest CT in October showed progression of the lesion. On further evaluation, including bronchoscopy, he was diagnosed with a drug-induced sarcoid reaction, and oral corticosteroid therapy was started, which led to improvement. Cases diagnosed as sarcoid reactions in the lung parenchyma are rare, and those presenting with infiltrative shadows are particularly uncommon. However, when pulmonary shadows increase after immune checkpoint inhibitor therapy, it is necessary to consider a sarcoid reaction in addition to malignancy or infection.

In August to September 2024, eight cases of Legionella pneumonia were diagnosed in our hospital following a period of heavy rain. The patients’ residences were clustered within a confined area spanning a 5-km radius. In all four cases in which the bacterial isolate was successfully obtained, Legionella pneumophila was identified, and the sequenced-based typing revealed the same sequence type, ST1646. The regional outbreak resolved spontaneously over approximately three weeks. Although the source of the infection could not be determined, the combination of elevated ambient temperatures and heavy rainfall was considered a potential contributing factor to the emergence of this cluster of legionellosis. In addition, because antigen testing and nucleic acid amplification tests do not yield viable isolates, submission of respiratory specimens for culture and preservation of recovered strains are essential for epidemiological investigation in similar regional outbreaks.