Low serum apolipoprotein AI levels in amyloidosis related to familial Mediterranean fever

Amyloidosis (A) related to familial Mediterranean fever (FMF) causes serious morbidity and mortality in children. Our study evaluates serum levels of apolipoprotein (Apo) AI, AII, B, and E and Apo AII/AI ratios as a non-invasive diagnostic tool for amyloidosis in children with FMF and FMF-A. Results were compared with those of patients with childhood nephrotic syndrome (NS) and healthy children (controls). Significantly lower serum levels of Apo AI (90.20+/-28.30 mg/dl) were documented in patients with FMF-A than in all other groups (FMF 126.89+/-51.07 mg/dl, NS 140.38+/-33.73 mg/dl, and controls 134.67+/-12.73 mg/dl) (P<0.01). Diagnostic sensitivity, specificity, and predictive value for this test were 85%, 80%, and 85%, respectively. Apo AII/AI ratio results were essentially equal in all groups (P>0.05). It is concluded that a decreased Apo AI serum level, but not Apo AII/AI ratio, is a useful, non-invasive test for the early diagnosis of FMF-A in children.