Enhanced liver fibrosis test in patients with psoriasis, psoriatic arthritis and rheumatoid arthritis

Background: The enhanced liver fibrosis (ELF) test has been introduced to screen, diagnose and/or monitor liver conditions in large groups of patients with liver diseases. It has not been used in inflammatory skin or joint diseases.
Objectives: To evaluate the distribution of the ELF test, apply existing cut-offs for hepatic patients and healthy controls, and compare it with the procollagen-3 N-terminal peptide (P3NP) test in patients with psoriasis (PSO), psoriatic arthritis (PsA) and rheumatoid arthritis (RA), and controls.
Methods: In total, 531 patients were included. Demographic, lifestyle and disease-specific data were collected. ELF and P3NP tests were performed.
Results: Prevalence of an increased ELF score (> 11) and P3NP was highest in patients with RA (7·7% and 6·1%, respectively) followed by patients with PSO (1·7% and 5·2%, respectively) and PsA (0·7% and 1·3%, respectively). Mean ± SD ELF scores for PSO, PsA and RA were, respectively, 9·09 ± 0·86, 8·96 ± 0·76 and 9·55 ± 1·04. All subgroups with moderate-to-severe disease severity had higher (> 9·8) ELF scores (PSO 27·0% vs. 18·3%; PsA 19·2% vs. 12%; RA 45·8% vs. 30·5%) and P3NP values. Distribution of the ELF score was smaller than the P3NP value [mean ± SD: 9·15 ± 0·92 (range 6·53-13·05) vs. 8·37 ± 4·30 (range 0·53-63·88)].
Conclusions: ELF score and P3NP are elevated in PSO, PsA and RA. ELF may be superior to P3NP alone, but further research should be done to validate the ELF test in determining susceptibility for developing liver fibrosis in PSO, PsA and RA.