RESUMO
Background: The role of chest computed tomography (CT) scan is controversial in the management of chronic cough patients with normal chest X-rays. We investigated the utilization pattern and diagnostic outcomes of chest CT scans using institutional routinely collected data (RCD) in South Korea. Methods: This is a retrospective analysis of adults with chronic cough (>8 weeks in duration) identified from routinely collected electronic health records (EHRs). Structured data were retrieved, including demographics, medical history, symptoms, and diagnostic test results (including chest X-rays and CT scans). Chest CT scan outcomes were classified into major abnormal findings (malignancy, infectious diseases, or other critical conditions that warrant immediate treatment decisions), minor abnormal findings (other abnormal findings), or normal CT. Results: A total of 5,038 chronic cough patients with normal chest X-rays were analyzed. Chest CT scans were performed in 1,006 patients. Prescription of CT scans was significantly associated with older age, male sex, smoking history, and physician-diagnosed history of lung disease. Only 8 of 1,006 (0.8%) patients had major abnormal findings (4 pneumonia, 2 pulmonary tuberculosis, and 2 lung cancer), while 367 (36.5%) had minor findings, and 631 (62.7%) had normal CT scans. However, no baseline parameters were significantly associated with major CT findings. Conclusions: Chest CT scans were frequently prescribed for chronic cough patients with normal chest X-rays, and abnormal findings were frequently found (37.3%). However, the diagnostic yield for malignancy or infectious disease were low (<1%). Given the potential radiation harm, a routine chest CT scan may not be warranted in chronic cough patients with normal chest X-rays.
RESUMO
BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine subtype 2 (TMPRSS2) are key proteins mediating viral entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although gene expressions of ACE2 and TMPRSS2 have been analyzed in various organs and diseases, their soluble forms have been less studied, particularly in asthma. Therefore, we aimed to measure circulating ACE2 and TMPRSS2 in the serum of asthmatics and examine their relationship with clinical characteristics. METHODS: Clinical data and serum samples of 400 participants were obtained from an asthma cohort. The soluble ACE2 (sACE2) and soluble TMPRSS2 (sTMPRSS2) level was measured by enzyme-linked immunosorbent assay, and the values underwent a natural log transformation. Associations between sACE2 and TMPRSS2 levels and various clinical variables were analyzed. RESULTS: The patients younger than 70 years old, those with eosinophilic asthma (eosinophils ≥ 200 cells/µL), and inhaled corticosteroids (ICS) non-users were associated with higher levels of sACE2. Blood eosinophils and fractionated exhaled nitric oxide levels were positively correlated with serum ACE2. In contrast, lower levels of sTMPRSS2 were noted in patients below 70 years and those with eosinophilic asthma, while no association was noted between ICS use and sTMPRSS2. The level of sTMPRSS2 also differed according to sex, smoking history, coexisting hypertension, and forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) ratio. The proportion of sputum neutrophils was positively correlated with sTMPRSS2, while the FEV1/FVC ratio reported a negative correlation with sTMPRSS2. CONCLUSION: The levels of ACE2 and TMPRSS2 were differently expressed according to age, ICS use, and several inflammatory markers. These findings suggest variable susceptibility and prognosis of SARS-CoV-2 infection among asthmatic patients.