OUR EXPERIENCE OF TRANSIENT ELASTOGRAPHY AND FIBROTEST ® IN MONITORING PATIENTS TAKING METHOTREXATE FOR PSORIASIS

Abstract

Frequent evaluation of liver enzymes, procollagen III peptide (PIIINP) levels and periodic liver biopsy are used to assess liver toxicity during methotrexate therapy for psoriasis. Monitoring PIIINP levels has reduced the need for liver biopsy, but some patients who proceed to biopsy do not have fibrosis or cirrhosis. The aim of our study was to evaluate transient elastography (TE) (Fibroscan; Echosens, Paris, France) and Fibrotest (Biopredictive, Cambridge, U.K.) in patients taking methotrexate for psoriasis. The v2-test was used for the comparison of dichotomous variables, and Mann-Whitney U-test for continuous variables. Forty-five patients (26 women, 58%), mean age 55 +/- 14.6 years, had TE assessments. The median cumulative methotrexate dose was 3.3 g (range 0.125-17.5, mean duration 6.0 years). The mean body mass index (BMI) was 28.7 +/- 7.2 kg m-2, and 62% were overweight or obese. Three patients (7%) had type 2 diabetes mellitus, and 13 (29%) had psoriatic arthritis (PsA). No patients reported excessive alcohol intake. Twenty-seven (60%) TE results were valid. The risk of TE failure was significantly higher in patients with a higher BMI (P < 0.01). Of the 27 valid TE results, 6 (22%) were abnormal (> 7.1 kPa). Two of 6 patients with abnormal TE results had persistently elevated PIIINP levels, and did not have PsA. Of 21 patients with normal TE results, 4 had persistently elevated PIIINP levels, and did not have PsA. Twenty-nine patients had Fibrotest, three (10%) of whom had abnormal Fibrotest results (> 0.31/> F1). One of these three patients had persistently elevated PIIINP levels, and did not have PsA. Five liver biopsies were done because of persistently elevated PIIINP levels, and showed mild or moderate steatosis. Three of these could have been avoided based on normal TE or Fibrotest results. Liver biopsy was contraindicated in some patients, and others decided to have an alternative drug rather than have a liver biopsy. Older age was the only characteristic associated with an abnormal TE result (P < 0.05). Older patients, those on methotrexate for a longer duration, and with a higher cumulative dose were more likely to have an abnormal Fibrotestresult (P < 0.05). We suggest that unnecessary liver biopsies may be avoided if abnormalities in at least two tests (PIIINP, TE or Fibrotest .) are required prior to biopsy. This strategy will need to be evaluated in prospective studies. Funding for Fibrotest was received from the City of Dublin Skin and Cancer Hospital Charity.