Prediction Value of KREBS Von Den Lungen-6 (KL-6) Biomarker in COVID-19 Patients: A Systematic Review and Meta-Analysis

Abstract

The SARS-CoV-2 (COVID-19) pandemic is a major issue that necessitates the use of cutting-edge disease prediction models. The aim of the study was to assess the existing evidence regarding association between Krebs von den Lungen-6 levels and COVID-19 severity. A literature search was performed on Web of Science, PubMed, Scopus and Cochrane Central Register of Controlled Trials databases from 1 January 2020 up to 2 August 2022. The electronic database search was supplemented by searching Google Scholar. In addition, reference lists of relative articles were also reviewed. KL-6 levels among COVID-19 positive vs. negative patients varied and amounted to 443.37 ± 249.33 vs. 205.73 ± 86.8 U/mL (MD = 275.33; 95%CI: 144.57 to 406.09; p < 0.001). The KL-6 level was 402.82 ± 261.16 U/mL in the severe group and was statistically significantly higher than in the non-severe group (297.38 ± 90.46 U/mL; MD = 192.45; 95%CI: 118.19 to 266.72; p < 0.001). The KL-6 level in the mild group was 272.28 ± 95.42 U/mL, compared to 268.04 ± 55.04 U/mL in the moderate COVID-19 group (MD = −12.58; 95%CI: −21.59 to −3.57; p = 0.006). Our meta-analysis indicates a significant association between increased KL-6 levels and SARS-CoV-2 infection. Moreover, KL-6 levels are significantly higher in patients with a more severe course of COVID-19, indicating that KL-6 may be a useful predictor to identify patients at risk for severe COVID-19.

Treatment of COVID-19 during the Acute Phase in Hospitalized Patients Decreases Post-Acute Sequelae of COVID-19

“…Indeed, a very large number of people at risk of PASC are relatively young without any comorbidities, so they currently do not meet the criteria for receiving treatment during the acute phase. However, there is very limited evidence on the association between treatments administered during the acute phase and predisposition of persistent symptoms [ 22 , 23 , 24 , 25 ]. There is an Italian cohort, where patients were treated in the acute phase of COVID-19 with monoclonal drugs, which obtained a 56% reduction in the risk of PASC appearance [ 26 ]; unlike our cohort, they required no oxygen therapy or hospital admission for SARS-CoV-2 infection.…”

“…Indeed, a very large number of people at risk of PASC are relatively young without any comorbidities, so they currently do not meet the criteria for receiving treatment during the acute phase. However, there is very limited evidence on the association between treatments administered during the acute phase and predisposition of persistent symptoms [22][23][24][25].…”

How has the COVID-19 pandemic affected patients with stroke? An emergency department perspective

“…However, the changing profile of admissions and the need for increased sanitary rigor has forced a change in the organization of emergency departments (ED) [2]. Early detection and isolation of patients with COVID-19 was crucial to be able to provide appropriate help to patients with other diseases [3,4]. At the same time, as pandemics spread, many of the medics struggled with burnout, anxiety, depression, or PTSD symptoms and experiences of fear, moral distress, and workplace violence [5][6][7][8].…”

Krebs von den Lungen-6 (KL-6) Levels in Post-COVID Follow-Up: Differences According to the Severity of COVID-19

“…It is elevated in interstitial lung diseases and acute respiratory distress syndrome and reflects alveolar epithelial injury [14,15]. In COVID-19, serum KL-6 levels combined with inflammatory parameters such as CRP act as biomarkers of poor prognosis and are higher in severe disease [16][17][18]. These levels can also predict the appearance of pulmonary fibrotic sequelae, both in patients treated in intensive care units and in hospital wards [19].…”