Clinical features of patients who visited the outpatient clinic for long COVID in Japan.

Background: The clinical course, comorbidity, and management of symptoms after the acute phase of coronavirus disease 2019 (COVID-19) remain controversial. Methods: This was a descriptive case series study, examining the characteristics of patients with longstanding symptoms related to COVID-19 who visited our outpatient clinic between 1 June and 31 December 2021. We analyzed patients' background, chief complaints, clinical course after COVID-19 onset, and clinical examination results. Results: A total of 90 patients with a mean age of 39.8 years were confirmed as having long COVID. The median time between diagnosis of COVID-19 and visiting our clinic was 66.8 days, and 89 patients (98.9%) were unvaccinated. Depression was the most common comorbidity (nine patients, 10.0%). The most common chief complaint was disturbance of smell and/or taste (35, 38.9%), followed by memory disturbance (22, 24.4%) and fatigue (29, 31.1%). Head MRI was performed for 42 (46.7%) patients, and the most common finding was sinusitis (four patients). Olfactory testing was conducted in 25 patients (27.8%) using a T&T olfactometer, and 14 patients (56%) had mild olfactory impairment. Of the five odors in the T&T, recognition of ß-phenylethyl alcohol was most impaired. Conclusions: This study describes the basic characteristics of long COVID in Japan. It suggests that long COVID is complex because it results in a wide range of symptoms.

Pathologic and Neuropathologic Study of a Case of COVID-19.

A 68-year-old woman with a history of schizophrenia developed coronavirus disease (COVID)-19 and was transferred to our hospital. Despite treatment, she died of respiratory failure 16 days after the onset. At the time of autopsy, polymerase chain reaction (PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA using swabs from the nasopharynx and the lung was positive; however, the cerebrospinal fluid was negative. An autopsy showed diffuse alveolar damage and recent multiple cerebral infarcts. Acute splenitis was observed with thrombi adhering to the vascular endothelium in areas of severe neutrophilic infiltration. Immunohistochemistry using an antibody against the SARS-CoV-2 nucleocapsid showed immunoreactivity along the hyaline membrane of the lung; however, the antibody showed no immunoreactivity in the medulla, the thalamus, the frontal lobe, and the pituitary. Future pathologic studies should clarify the mechanisms involved in a variety of clinical and pathological changes related to COVID-19.