Assessment of bone metabolism biomarkers in serum and saliva of cirrhotic patients

Objective To assess the serum and salivary levels of biomarkers related to bone metabolism in cirrhotic patients as well as the evidence of osteoporotic changes on panoramic radiographs. Materials and methods Thirty-eight cirrhotic patients underwent anamnesis and physical examination. Specimens of blood and saliva were collected for evaluation by using Luminex™ xMAP technology to quantify RANKL, OPG, IL-1β, IL-6 and TNF-α. Panoramic radiographs were evaluated based on the mandibular cortical index (MCI) and the resulting data were compared to the expression of biomarkers in serum and saliva. Descriptive data analysis was performed and the Mann–Whitney’s test and Spearman’s correlation were used. Results Most of the sample consisted of males (68.4%) who had cirrhosis mostly resulting from alcoholism (28.9%). Median concentration values of RANKL (74.44 pg/mL), IL-1 β (45.91 pg/mL), IL-6 (67.69 pg/mL) and TNF-α (5.97 pg/mL) in saliva were higher than those observed in serum. In 72.7% of the panoramic radiographs, MCI was found to be suggestive of osteoporotic changes. No statistically significant correlation was observed between salivary and serum expressions of biomarkers or between biomarkers and MCI. Conclusion RANKL, OPG, IL-1β, IL-6 and TNF-α are expressed differently in serum and saliva and the concentration of these biomarkers is not related to MCI. Clinical relevance This study contributes to the study of the mechanisms of osteoporosis in cirrhotic individuals.