Diagnostic Values of Clusterin and α-Klotho Levels in Patients with Sarcoidosis

Aim: Sarcoidosis is a multifactorial disease with unknown aetiology and characterized by non-caseous granulomatous inflammation. The pathogenesis of sarcoidosis is defined as inflammation and autoimmune activation. Here, we aimed to evaluate plasma clusterin (CLU) and α-klotho levels in those with sarcoidosis.                                        

Patients and methods: Forty patients with sarcoidosis (mean age: 52.10±12.60 years; 12 males, 28 females) and 40 healthy volunteers (mean age: 37.40±18.20 years; 12 males, 28 females) were enrolled into the study. Blood samples were drawn from both groups, and plasma CLU and α-klotho levels were investigated by enzyme-linked immunosorbent assay (ELISA) technique.                                                               

Results: Patients with sarcoidosis had significantly higher plasma CLU levels (309.73±40.68 ng/mL), compared with healthy controls (117.86±102.03 ng/mL) (p=0.005). The plasma levels of α-klotho were measured as 5.34±7.30 in the sarcoidosis patients and 7.21±9.84 ng/mL in the controls. A minimal decrease was observed, but there was no statistically significant difference (p=0.338). The hemoglobin levels of sarcoidosis patients were decreased, when compared with the control group (12.93±1.02 g/dL vs 14.06±1.50 g/dL) (p=0.012).                                                                    

Conclusion: We concluded that sarcoidosis is associated with high levels of CLU. Plasma CLU may be a potential biomarker of sarcoidosis. Based on literature and to the best of our knowledge, this is the first study to provide insight in the determination of plasma levels of CLU and α-klotho in sarcoidosis. Further and comprehensive investigations are needed to clarify the entity.