Multilocular thymic cyst detected during COVID­19 treatment in an HIV­positive adult man: A case report and literature review.

A multilocular thymic cyst (MTC) is a rare mediastinal tumor with multiloculated cyst-like structures in the anterior mediastinum. This tumfor is associated with inflammatory diseases, including human immunodeficiency virus (HIV) infection. The present study reports a case of MTC detected during coronavirus disease 2019 (COVID-19) treatment in an adult who was tested HIV positive. An anterior mediastinal tumor was incidentally detected on computed tomography in a 52-year-old man with a 20-year history of HIV infection on the 9th day of COVID-19. The patient was asymptomatic with no notable physical findings. Magnetic resonance imaging revealed a 28-mm bilocular cyst. Robot-assisted thoracoscopic tumor resection was performed. Pathological examination showed that the cyst was lined with squamous or cuboidal epithelium, and the cystic lesion wall was mainly composed of thymic tissue with follicular hyperplasia. Based on these findings, the patient was diagnosed with MTC. To date, only 15 MTC cases have been reported in patients with HIV, and the majority of cases showed HIV infection-related symptoms such as lymphoid interstitial pneumonia and parotid gland enlargement. The present case was atypical for an HIV-related MTC because it did not involve HIV infection-related symptoms, suggesting the possibility for an alternative etiology such as COVID-19. Further reports on MTC development in patients with COVID-19 are required to elucidate the relationship between MTC and COVID-19.

Relationship between surgical field contamination by patient's exhaled air and the state of the drapes during eye surgery.

The coronavirus disease (COVID-19) pandemic has led to a dramatic increase in facemask use. Consequently, it has been reported that exhaled airflow toward the eyes can cause the dispersal of bacteria into the eyes, potentially increasing the incidence of postoperative endophthalmitis. In addition to wearing a facemask, gaps between the surgical drape and skin can also direct exhaled airflow toward the eyes. Here, we aimed to examine how the risk of contamination varies depending on the state of the drapes. We used a carbon dioxide imaging camera to visualize changes in exhaled airflow under different drape conditions and a particle counter to evaluate changes in the number of particles around the eye. The results revealed airflow present around the eye and a significant increase in the number of particles when the nasal side of the drape was detached from the skin. However, when a metal rod called "rihika" was used to create space above the body, the airflow and number of particles were significantly reduced. Thus, if drape coverage becomes incomplete during surgery, exhaled airflow toward the eye may contaminate the surgical field. On hanging up the drape, airflow can escape in the direction of the body, potentially preventing contamination.

An Autopsy Report of a Case with Cerebral Infarction Complicated by Coronavirus Disease 2019 Infection.

We herein report a case of cerebral infarct in a patient with coronavirus disease 2019 (COVID-19) infection who died of aspiration pneumonia. The postmortem examination of the brain revealed embolic infarct with negative findings on quantitative reverse transcription polymerase chain reaction (qRT-PCR) as well as immunohistochemistry to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The systemic examination only revealed low copy numbers of SARS-CoV-2 in the bronchus. This is the first and so far only autopsy case of COVID-19 infection with pathologic and virologic findings of the postmortem brain in Japan.

COVID-19 mRNA vaccine-related interstitial lung disease: Two case reports and literature review.

The Pfizer-BioNTech mRNA vaccine (BNT162b2) is an effective and well-tolerated coronavirus disease 2019 (COVID-19) vaccine. However, rare adverse events have been reported. We report two cases of COVID-19 mRNA vaccine-related interstitial lung disease (ILD). A 67-year-old man and a 70-year-old man with underlying ILD presented to our hospital with a few days of fever and respiratory symptoms after receiving the BNT162b2 vaccine. Drug-related pneumonitis due to the COVID-19 mRNA vaccine was diagnosed. One case was diagnosed with lymphocytic alveolitis by bronchoalveolar lavage fluid and transbronchial lung cryobiopsy. Both patients were successfully treated with corticosteroids, and they attended outpatient clinics thereafter. Although the safety and efficacy of COVID-19 vaccines have been established, further studies are needed to estimate long-term data and reports of rare adverse reactions. We present the clinical course of two cases, review previously published case reports on COVID-19 mRNA vaccine-related ILD and discuss the relevant findings.

Autopsy findings of a patient with severe COVID-19 treated with long-term extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO) therapy in patients with coronavirus disease 2019 (COVID-19) has a low frequency of use, and thus pathological findings in such patients are valuable. In this case report, a 62-year-old man with a history of hypertension presented with a runny nose. After an at-home COVID-19 positive test, he developed dyspnea and fever. Once admitted to our hospital, his oxygenation worsened, and ECMO was initiated. He died from respiratory failure 69 days after ECMO induction. Macroscopically, the lungs gained mass, were partially consolidated, and were airless. Histological analysis revealed diffuse bronchial epithelial metaplasia and adenoid metaplasia in the alveolar epithelium. Although the lung parenchyma was partially preserved, there was organizing and fibrosis that filled pulmonary alveolus due to COVID-19 and changes resulting from disuse and long-term ECMO.