Evaluation of an immunochromatography-based rapid antigen test, Inspecter Kowa® SARS-CoV-2, using saliva specimens for the detection of SARS-CoV-2.

BACKGROUND: In the context of the coronavirus disease 2019 (COVID-19) pandemic, a rapid and reliable point-of-care test is an essential tool for controlling the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In particular, an immunochromatography test (ICT) that uses saliva specimens for rapid antigen detection not only reduces the risk of secondary infections but also reduces the burden on medical personnel. METHODS: The newly developed salivary antigen test kit "Inspecter Kowa® SARS-CoV-2" is an ICT to which saliva specimens can be directly applied. We evaluated its usefulness in comparison with reverse transcription quantitative PCR (RT-qPCR) and the Espline® SARS-CoV-2 Kit for the detection of SARS-CoV-2 using nasopharyngeal swab specimens. In this study, 140 patients with suspected symptomatic COVID-19 who visited our hospital were enrolled, and nasopharyngeal swab and saliva specimens were collected after they consented to participate in the study. RESULTS: Inspector Kowa SARS-CoV-2 was positive in 45 of 61 (73.8%) saliva that were positive by RT-qPCR and the Espline® SARS-CoV-2 Kit was also positive in 56 of 60 (93.3%) Np swabs that were positive by RT-qPCR. Good antigen detection was achieved by ICT with saliva and nasopharyngeal swab specimens when viral load was ≥105 copies/mL, whereas detection sensitivity was low when viral load was <105 copies/mL, especially in saliva specimens. CONCLUSION: This ICT for the detection of SARS-CoV-2 salivary antigen is an attractive tool that does not require specialized equipment and allows patients to perform the entire process from sample collection to self-diagnose and to reduce the burden on medical care during a pandemic.

Pure red cell aplasia accompanied by COVID-19 successfully treated using cyclosporine.

A 67-year-old Japanese man was admitted to our hospital with severe coronavirus disease 2019 (COVID-19) in March 2020. Mechanical ventilation was initiated 8 days after admission, due to severe respiratory failure. Multiple severe complications such as liver dysfunction, arrhythmia, brain infarction, and venous thromboembolism were also observed. We initially diagnosed Coombs test-positive warm autoimmune hemolytic anemia. Corticosteroids proved ineffective and anemia worsened with severe erythroid hypoplasia (0.5% erythroblasts in bone marrow), so we diagnosed pure red cell aplasia (PRCA). We also identified massive infiltration of cytotoxic T-lymphocytes expressing CD8, granzyme B, and perforin in bone marrow. Systemic cyclosporine was started, with full resolution of anemia and no need for blood transfusions after 4 weeks. We believe that this represents the first report of COVID-19-associated PRCA successfully treated using cyclosporine.

Successful Treatment of Eosinophilic Granulomatosis With Polyangiitis: A Case of Refractory Peripheral Neuropathy and Comorbid Chronic Progressive Pulmonary Aspergillosis Treated With Mepolizumab.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic necrotizing vasculitis accompanied by granulomas and eosinophilic inflammation, exhibiting marked peripheral blood eosinophiliaandasthma. Neuropathy is a difficult-to-treat common manifestation that frequently remains after achieving clinical remission with current therapy in a subpopulation of patients with EGPA with or without life-threatening organ involvement. Refractory neuropathy regularly reduces the quality of life and requires glucocorticoids (GCs) and/or immunosuppressants for a long time. Long-term immunosuppressive therapy is a factor associated with a high risk of adverse effects. Mepolizumab, at three times the dose for severe asthma, provides benefits to induce the remission of relapsing or refractory EGPA and to reduce the doses of GC. Here, we present a case of EGPA successfully treated with mepolizumab at the reference dose for severe asthma. In this case, mepolizumab resolved peripheral neuropathy resistant to corticosteroids, immunosuppressants, and intravenous immunoglobulin and contributed to the improvement of comorbid chronic pulmonary aspergillosis during GC dose reduction.

Simultaneous bilateral spontaneous pneumothorax in a patient with anorexia nervosa.

Anorexia nervosa causes various complications accompanying weight loss and malnutrition. Although bilateral spontaneous pneumothorax (SBSP) is uncommon, caution is needed in anorexia nervosa because this complication can be fatal. We encountered a 17-year-old girl with SBSP from emphysematous pulmonary changes due to anorexia nervosa. She was hospitalized with SBSP during treatment for anorexia nervosa. Chest tube drainage was started on admission, but no improvement was achieved. Surgery was therefore performed. Lung lesions on surgical specimens demonstrated malnutrition-induced emphysematous changes, a risk factor for SBSP. Attention should be paid to the occurrence of SBSP during the clinical course of anorexia nervosa.