There is accumulating evidence of the involvement of biological metal imbalance in the progression of amyloid diseases such as Alzheimer's, Parkinson's and prion diseases. However, the mineral status in patients affected with familial amyloidotic polyneuropathy (FAP) has not been investigated. It is the aim of this study to determine the metal concentrations in the serum and in the transthyretin (TTR) amyloid fibrils of FAP amyloidogenic TTR (ATTR) V30M patients. Multi-elemental analysis of 17 metals by high-resolution inductively coupled plasma mass spectrometry (ICP-MS) revealed a significant decrease of the metals Fe, Cu, Zn, Cs and Ba in the serum of FAP patients (mean age 38.5 +/- 8.3 years; duration of disease 4 +/- 2.6 years) in comparison with that of healthy individuals (mean age 36.2 +/- 9.2 years). On the other hand, these metals, except Cs, were found at high levels in the amyloid fibrils of FAP patients (mean age 55.8 +/- 9.2; duration of disease 6.5 +/- 1.3 years) compared with other metals. These findings firstly suggest that the mineral status could be a candidate factor, which participates in the wide spectrum of clinical pictures of FAP patients.