Acute hypercapnic respiratory failure in patients with obesity hypoventilation syndrome during the COVID-19 pandemic: Four case reports.

Obesity hypoventilation syndrome (OHS) can cause acute hypercapnic respiratory failure (AHRF). The onset of AHRF in four patients with OHS during the coronavirus disease 2019 (COVID-19) pandemic is reported in this study. Two men (23 and 45 years old) and two women (both 77 years old) presented to our hospital with AHRF. In the two elderly women, a prolonged supine position due to falls seemed to be the cause of AHRF. Treatment was started with bilevel positive airway pressure for all patients. While one patient died, the condition of the other three improved; they were discharged with continuous positive airway pressure. AHRF due to OHS was rarely reported in the rural region of Japan. It is suggested that increased rates of obesity due to lifestyle changes during the COVID-19 pandemic may be responsible for an increase in the prevalence of OHS-associated AHRF.

Methicillin-resistant Staphylococcus aureus Necrotizing Bronchitis after Radiotherapy in Combination with Axitinib.

A 38-year-old man with renal cell carcinoma was referred to our hospital because of a productive cough. He had received radiotherapy for lung metastasis and been treated with axitinib. Bronchoscopy revealed necrosis in the bronchi of the right middle and lower lobes. Culture of the necrotic bronchial specimen revealed methicillin-resistant Staphylococcus aureus (MRSA). Although radiotherapy in combination with axitinib carries a risk of causing airway toxicity, MRSA necrotizing bronchitis has not been reported. Physicians should consider the possibility of infectious necrotizing bronchitis if irradiated patients show prolonged respiratory symptoms.

Complete remission of advanced lung adenocarcinoma with first-line pembrolizumab monotherapy: Two case reports.

Immune checkpoint inhibitors (ICIs) are clinically used for treating advanced lung cancer, and some patients have achieved complete remission (CR) with ICI therapy in clinical trials. However, reports summarizing the clinical courses of such patients are limited. We report two cases of lung adenocarcinoma in which CR was achieved with first-line pembrolizumab monotherapy, and the therapeutic effect was maintained after treatment completion. Specific patients can achieve CR, even those who do not meet the previously reported predictors of treatment response other than high programmed death-ligand 1 expression. Thus, biomarkers that can accurately predict the clinical efficacy of ICIs are warranted.