Autotaxin: A Potential biomarker for primary biliary cholangitis.

BACKGROUND

In some patients especially those AMA negative, the diagnosis may be a challenge requiring liver biopsy. This study determined whether autotaxin, a secreted lysophospholipase D encoded by the exonucleotide pyrophosphatase phosphodiesterase 2 gene, can be used as a serum biomarker for primary biliary cholangitis.

METHODS

Plasma samples were collected from 103 patients with PBC and 74 healthy controls. autotaxin levels were determined by Enzyme-linked immunosorbent assay, and its predictive value for diagnosing primary biliary cholangitis was analysed. The relationship between autotaxin and the clinical data was also evaluated.

RESULTS

Autotaxin levels in patients with primary biliary cholangitis were significantly higher than those in healthy control (median: 60.7 ng/ml vs. 32.6 ng/ml, P < 0.001). The cut-off value of autotaxin in patients with primary biliary cholangitis was 38.5 ng/ml, and the positivity rate was 33.9 %, calculated twice. The sensitivity, specificity, positive predictive value, and negative predictive value were 54.3 %, 93.1 %, 84.4 %, and 74.8 %, respectively, and the area under the curve was 0.73. Autotaxin level positively correlated with immunoglobulin M level (r = -0.22, P < 0.05) and Ludwig's classification (r = 0.76, P < 0.01) in patients with primary biliary cholangitis. The positivity rate of autotaxin (50.0 %) was higher than that of anti-sp100 (16.7 %) and anti-gp210 (11.1 %) antibodies in anti-mitochondrial antibody -negative patients with primary biliary cholangitis.

CONCLUSIONS

Autotaxin may be an effective noninvasive biomarker used in diagnosis, prognosis of primary biliary cholangitis, particularly in anti-mitochondrial antibody -negative patients.