Association of serum Krebs von den Lungen-6 and chest CT as potential prognostic factors in severe acute respiratory syndrome SARS-CoV-2: a preliminary experience

• Published in: Radiologia medica 2022-07, Vol.127 (7), p.725-732
• Main Authors: Anastasi, Emanuela, Manganaro, Lucia, Guiducci, Elisa, Ciaglia, Simone, Dolciami, Miriam, Spagnoli, Alessandra, Alessandri, Francesco, Angeloni, Antonio, Vestri, Annarita, Catalano, Carlo, Ricci, Paolo
• Format: Article
• Language: English
• Subjects: Biomarkers; Blood; Chest; Chest Radiology; Computed tomography; Coronaviruses; COVID-19; Diagnostic Radiology; Imaging; Interventional Radiology; Medical imaging; Medicine; Medicine & Public Health; Neuroradiology; Radiology; Serum proteins; Severe acute respiratory syndrome coronavirus 2; Ultrasound; Workflow
• ISSN: 1826-6983; 0033-8362; 1826-6983
• DOI: 10.1007/s11547-022-01504-6

Purpose To correlate in COVID-19 pneumonia CT-based semi-quantitative score of pulmonary involvement with high serum levels of KL-6, a biomarker of disease severity. Methods Between March 28 to May 21, 2020, 196 patients with strong suspicion of SARS-CoV-2 were evaluated with RT-PCR for SARS-CoV-2, chest CT scan and blood test, including KL-6 serum protein, in our Emergency Unit. The final population included only patients who underwent blood sampling for KL-6 within 5 days from CT scan ( n = 63), including n  = 37 COVID-19-positive patients and n  = 26 with negative RT-PCR testing for SARS-CoV-2 (control group). A semi-quantitative CT score was calculated based on the extent of lobar involvement (0:0%; 1, < 5%; 2:5–25%; 3:26–50%; 4:51–75%; 5, > 75%; range 0–5; global score 0–25). Results CT score was significantly correlated with serum value of KL-6 ( r  = 27, p  = 0.035). This correlation was also present in COVID-19 positive patients ( r  = 0.423, p  = 0.009) and CT score median value was significantly higher in patients with high KL-6 value (> 400 U/mL; 12.00, IQR 5.00-18.00, p-value 0.027). In control group, no statistically significant correlation was found between CT score and KL-6 value and CT score was higher in patients with high KL-6, although this difference was not statistically significant (5.00, IQR:1.75–8.00 versus 3.50, IQR:2.00–6.50). "Crazy paving" at the right upper ( n  = 8; 61.5%) and middle lobe ( n  = 4; 30.8%) and "consolidation" at the middle lobe (n=5; 38.5%) were observed in COVID-19 group with a significant difference between patients with high KL-6 value. Conclusion CT score is highly correlated with KL-6 value in COVID-19 patients and might be beneficial to speed-up diagnostic workflow in symptomatic cases.