The use of transient elastography and FibroTest for monitoring hepatotoxicity in patients receiving methotrexate for psoriasis.

IMPORTANCE There is a need for noninvasive tools to monitor hepatotoxicity in patients with psoriasis who are receiving methotrexate sodium. OBJECTIVE To evaluate the use of transient elastography (TE) and FibroTest (FibroSURE in the United States), an indirect serum marker of fibrosis, in this population. DESIGN, SETTING, AND PARTICIPANTS Patients receiving methotrexate therapy for psoriasis between January 2008 and September 2009 were recruited from a dermatology outpatient department. Transient elastography and FibroTest were performed, and patients with abnormal results were considered for liver biopsy. Serial procollagen III peptide (PIIINP) results were recorded. INTERVENTIONS Transient elastography uses pulse-echo ultrasonography to measure liver stiffness, and this result is an indirect measure of hepatic fibrosis. FibroTest is an indirect serum marker of hepatic fibrosis. MAIN OUTCOMES AND MEASURES Procollagen III peptide, TE, and FibroTest results, as well as the need for liver biopsy in this cohort. RESULTS Seventy-seven patients (41 male [53%]) were included. Fifty (65%) patients had a valid TE assessment, and 9 (18%) had an abnormal result (range, 7.1-11.3 kPa). Being overweight or obese increased the possibility of obtaining an invalid TE result significantly (P = .01). On univariate analysis body mass index (r = 0.40, P = .005) and age (r = 0.52, P = .005) were correlated with abnormal TE results. Seventy-one patients received a FibroTest and 11 of 70 analyzed (16%) had an abnormal result (METAVIR score >F1). Age (r = 0.31, P = .009), cumulative methotrexate dose (r = 0.31, P = .01), and duration of methotrexate therapy (r = 0.36, P = .002) were correlated with abnormal FibroTest results. There was no correlation between PIIINP levels and TE results or between PIIINP levels and FibroTest results. Steatosis was demonstrated in all 5 patients who received liver biopsies during the study. Two patients had hepatic fibrosis, with 1 showing a sinusoidal pattern of fibrosis attributed to steatohepatitis. CONCLUSIONS AND RELEVANCE Transient elastography and FibroTest are effective noninvasive tools for monitoring hepatotoxicity in patients receiving methotrexate for psoriasis. We propose that the need for liver biopsy could be reduced if abnormalities in at least 2 tests (serial PIIINP, TE, or FibroTest) are required before biopsy is considered. This strategy should be evaluated in prospective studies.