Objectives: To assess subclinical inflammation in heterozygous carriers of Mediterranean fever (MEFV) gene mutations, analysis of classical inflammation markers and S100A12 was performed.
Methods: Exons 2, 3, and 10 of the MEFV gene, C-reactive protein (CRP), serum amyloid A protein (SAA), procalcitonin (PCT), and S100A12 concentrations, erythrocyte sedimentation rate (ESR), and differential blood count were analysed in apparently healthy parents (n=26) of homozygous children with familial Mediterranean fever (FMF). Their general health condition was assessed by a standardised questionnaire. In order to collect data on the disease course, subjects were reevaluated after 5 years by means of telephone interview and/or questionnaire.
Results: Twenty-two individuals with one typical mutation in the MEFV gene were included. Mean values (mean±SEM) of classical inflammation markers were within the normal range (ESR of 11.7±1.9 mm/h, SAA 4.7±0.4 mg/l, CRP 0.26±0.04 mg/dl), while PCT was non-detectable in all cases (<0.1 μg/l). Eleven subjects showed elevated S100A12 levels [>140 ng/ml] with a mean concentration of 205±43 ng/ml. Thus, the mean value of S100A12 was 1.5-fold higher than the regular cut-off.
Conclusions: 50% of the heterozygous MEFV mutation carriers exhibited elevated S100A12 levels, supporting previous observations that S100 molecules are very sensitive biomarkers of subclinical inflammation. Possibly, S100A12 could be a prognostic biomarker to detect individuals at risk of FMF manifestation who might benefit from colchicine therapy.