Significance of serum Krebs von den Lungen-6 in systemic sclerosis

Background Systemic sclerosis (SSc) is a well-known multi-system connective tissue disease, it has an unidentified aetiology that is characterised by abnormal immune system activation, vascular injury, which may progress to faulty neovascularization and inadequate vessel remodelling, and tissue scarring of the skin, lungs, and other internal viscera. Krebs von den Lungen-6 is a kind of transmembrane glycoprotein of type II alveolar epithelial cells and is specific for determining its damage. Regardless of the cause, serum Krebs von den Lungen-6 levels have been investigated in interstitial lung disease (ILD) of several etiologies and have been found to be a significant serum marker for ILD. The current research aims to look into the relationship between serum Krebs von den Lungen-6 levels and disease severity and clinical manifestations, specifically interstitial pulmonary fibrosis, in patients with SSc. In this study, 30 patients with systemic sclerosis and 30 control subjects-15 dermatomyositis patients and 15 healthy volunteers- were also incorporated to see if the change in serum Krebs von den Lungen-6 levels is specific for SSc as dermatomyositis is another connective tissue disorder with lung affection.Results A statistically significant difference (P < 0.001) in the median value of Krebs von den Lungen-6 when compared to the control groups was observed, which was 447.95 (145.68-817.98) in the SSc patients group, 158.80 (130.00-730.70) in the dermatomyositis group, and 48.10 (39.50-103.90) in the healthy control group. A significantly higher median value of Krebs von den Lungen-6 in ground glass, honeycombing, and nodular HRCT was established, with P-value (P < 0.001). There was a highly statistically significant discrepancy in the median Krebs von den Lungen-6 value between patients with ILD (717.7) and patients without ILD (145.7) with P-value (P < 0.001). A statistically significant positive correlation was found between Krebs von den Lungen-6 (U/ml) and Disease duration (years), Medsger severity scale, Digital ulceration, modified Rodnan skin score (MRSS), and P-value (P < 0.05).Conclusion Krebs von den Lungen-6 could be a scleroderma biomarker. It has been linked to the development and severity of interstitial lung disease in systemic sclerosis patients and may shed light on the pathophysiology of some fibrotic lung changes.