Substantia nigra echogenicity in Parkinson's disease: relation to serum iron and C-reactive protein.

In Parkinson's disease (PD), substantia nigra hyperechogenicity (SN-h) has been related to both, local iron accumulation and microglia activation. We analysed its relationship in PD patients with serum iron (n = 31) and C-reactive protein (CRP; n = 193). SN-h correlated with lower CRP and iron levels. Also, patients with a first-degree relative with PD had lower iron levels. Microglia activation, if reflected by SN-h, may be therefore unrelated to serum CRP. Findings support the idea that SN-h indicates inherited alteration of iron metabolism.