Coronavirus disease 2019 (COVID‐19) is one of the most pressing health problems of this century, but our knowledge of the disease is still limited. In this study, we aimed to examine serum‐soluble urokinase plasminogen activator receptor (suPAR) and kidney injury molecule 1 (KIM‐1) levels based on the clinical course of COVID‐19. Our study included 102 patients over the age of 18 who were diagnosed as having COVID‐19 between September 2020 and December 2020 and a control group of 50 health workers over the age of 18 whose severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) PCR results were negative. KIM‐1 was measured by ELISA and suPAR by suPARnostic™ assay. Analysis of previously identified variables of prognostic significance in COVID‐19 revealed high neutrophil to lymphocyte ratio, lactose dehydrogenase, prothrombin time, C‐reactive protein, PaO₂/FiO₂, D‐dimer, ferritin, and fibrinogen levels in patients with severe disease (p < 0.05 for all). KIM‐1 and suPAR levels were significantly higher in COVID‐19 patients compared to the control group (p = 0.001 for all). KIM‐1 level was higher in severe patients compared to moderate patients (p = 0.001), while suPAR level was lower (p = 0.001). KIM‐1, which is believed to play an important role in the endocytosis of SARS‐CoV‐2, was elevated in patients with severe COVID‐19 and may be a therapeutic target in the future. SuPAR may have a role in defense mechanism and fibrinolysis, and low levels in severe patients may be associated with poor prognosis in the early period.

The COVID‐19 pandemic, which has ravaged our world for more than a year, still shapes our agenda with a scale of intensity that fluctuates over time. In our study, we aimed to determine the correlation between serum migration inhibitory factor (MIF) level and disease severity in COVID‐19 with different prognoses. Between 15 October 2020 and 20 January 2021, 110 patients over the age of 18 who were diagnosed with COVID‐19 and 40 volunteer healthcare personnel were included in our study. MIF levels were measured by enzyme‐linked immunosorbent assay. In the comparison of serum MIF values in the patient and control group, it was observed that the MIF level was significantly higher in patients with both moderate and severe COVID‐19 levels compared to the control group (p = 0.001, 0.001). In the comparison of serum MIF values of moderate to severe COVID‐19 patients, it was observed that MIF level was higher in severe patients (p = 0.001). In the receiver operating characteristic curve analysis performed to differentiate between severe and moderate COVID‐19 patients with MIF levels, the area under the curve was observed as 0.78. When the cutoff value of the MIF level was taken as 4.455 ng/ml, the sensitivity was 83% and the specificity was 62%. Failure to adequately balance the pro‐inflammatory cytokines synthesized in COVID‐19 with anti‐inflammatory effect is the most important reason for the aggravation of the disease course. Playing a role in pro‐inflammatory cytokine synthesis, MIF can provide important information about the disease prognosis in the early period.

In addition to the highly variable clinical presentation of acute COVID‐19 infection, it can also cause various postacute signs and symptoms. This study aimed to evaluate patients with postacute COVID‐19 over 12 weeks of follow‐up. The study included 151 patients who were diagnosed with COVID‐19 by real‐time polymerase chain reaction of a nasopharyngeal swab 1 month earlier, had radiologic findings consistent with COVID‐19 pneumonia, and presented to the post‐COVID‐19 outpatient clinic between May and August 2021. The patients were divided into three groups based on COVID‐19 severity: nonsevere pneumonia (Group 1), severe pneumonia (Group 2), and severe pneumonia requiring intensive care (Group 3). Evaluation of laboratory parameters at 4 and 12 weeks showed that Group 3 had a higher lactose dehydrogenase (LDH) level and a lower mean platelet volume than the other groups at both time points (p = 0.001 for all). Group 3 also had lower percent predicted forced vital capacity (FVC%), percent predicted forced expiration volume in 1 s (FEV1%), and percent predicted diffusion capacity of the lungs for carbon monoxide divided by alveolar volume (DLCO/VA%) compared to Groups 1 and 2 at Week 4 (p = 0.001, 0.004, 0.001, respectively) and compared to Group 1 at 12 weeks (p = 0.002, 0.03, 0.001, respectively). Patients with persistent dyspnea at 12 weeks had significantly lower FEV1%, FVC%, DLCO/VA%, and saturation levels in room air and significantly higher LDH, pro‐BNP, D‐dimer, and heart rate compared to those without dyspnea (p = 0.001 for all). Although the lungs are most commonly affected after COVID‐19 infection, vascular and endothelial damage also causes multisystem involvement. Our study indicates that laboratory values, radiological signs, and pulmonary functional capacity improved in most patients after 12 weeks of follow‐up.

Objective: Coronavirus 2019 disease presents in a spectrum that can range from mild viral infection to pneu- monia. Common symptoms of coronavirus disease 2019 pneumonia include cough, sputum, and shortness of breath. High-frequency chest wall oscillation is a pulmonary rehabilitation method used for the recovery of pulmonary functions and removal of secretions in the lungs. The aim of the study was to evaluate the efficacy of high-frequency chest wall oscillation on patients with coronavirus disease 2019 pneumonia. Materials and Methods: In this study, 100 patients, between 18 and 70 years old, with a positive polymerase chain reaction result for coronavirus disease 2019, were included. Standard medical treatment was applied to all patients. In group rehabilitation, high-frequency chest wall oscillation treatment was applied twice a day for 20 minutes for 5 days. No additional intervention was made to the control group. Pulmonary function tests and oxygenation were evaluated on the first and fifth days. Patients’ high-flow oxygen, non-invasive mechani- cal ventilation, and invasive mechanical ventilation needs were evaluated and recorded. Results: Compared with the control group, the forced expiratory volume in 1 second, forced vital capacity, and peak expiratory flow rates were statistically higher in the rehabilitation group on the fifth day (P < .05). On evaluating the oxygenation of patients, the fifth day to first-day oxygen saturation difference was signifi- cantly higher in rehabilitation group than in control group (P < .05). Furthermore, the number of patients who needed non-invasive mechanical ventilation was lower in the rehabilitation group (P < .05). Conclusion: This study demonstrated that pulmonary rehabilitation applied with the high-frequency chest wall oscillation device in patients with coronavirus disease 2019 in the early period contributed to the improvement of oxygenation by providing significant improvement as observed in the pulmonary function tests of the patients. Cite this article as: Çelik M, Murat Yayık A, Kerget B, et al. High-frequency chest wall oscillation in patients with COVID-19: A pilot feasibility study. Eurasian J Med 2022;54(2):150-156.

Background: In obstructive sleep apnea (OSA), recurrent upper airway obstruction and apnea/hypopnea episodes result in endothelial dysfunction, which leads to the release of many proinflammatory cytokines and reactive oxygen species (ROS). ROS induces NLRP3, a protein involved in the synthesis of interleukin (IL)-1 and IL-18; vaspin is a serine protease inhibitor that has an important role in suppressing the activation of NLRP3 inflammasome. In this study, we aimed to investigate the effect of NLRP3 rs10159239 (rs9239) and vaspin rs2236242 (rs6242) single nucleotide polymorphisms (SNPs) on OSA development. Methods: This study included 220 individuals who underwent polysomnography (118 patients with OSA and 102 healthy controls). NLRP3 rs9239 and vaspin rs6242 mutation frequencies were analyzed. Results: The NLRP3 rs9239 SNP genotype analysis revealed no statistically significant differences between the OSA and control groups. In the vaspin gene analysis, the rs6242 AA genotype was significantly more frequent in the OSA group compared with the control group, while the AT genotype was more frequent in controls (P = 0.004, P = 0.02). Comparison of rs6242 allele levels showed that the A allele was significantly more frequent in OSA patients than in controls (P = 0.03). The AA genotype was significantly more frequent in patients with severe OSA than in patients with mild or moderate OSA and the control group (P = 0.001 for all). Serum vaspin levels were significantly lower in carriers of the AA genotype than those with AT and TT genotypes (P = 0.001). Conclusion: The vaspin rs6242 SNP AA genotype increased susceptibility to OSA, while the AT genotype appeared to be protective. The lower plasma vaspin levels in OSA compared with the control group and in patients with the AA genotype suggest that vaspin may be a protective biomarker for OSA.