Hereditary hemochromatosis: population screening based on phenotype in Brazilian blood donors

A population of blood donors was screened for hereditary hemochromatosis (HH) based on the phenotype strategy in accordance with the European consensus.

Nonfasting serum samples were obtained from 1,050 donors. Transferrin saturation (TS) was measured using a threshold of 45%. Donors with a TS > or = 45% were retested in a fasting sample. If TS was elevated, the participants were tested for iron overload by ferritin measurement followed by genetic testing. All donors underwent clinical and laboratory workup for expression of the disease.

A total of 775 (74.6%) of the donors were men, 749 (72.1%) white, and had a mean age of 30 years (range, 8-60 years). Mean +/- SD TS was 25.9% +/- 13.1% (range, 2.1%-85.8%), and there were 58 (5.6%) donors with a TS > or = 45%. Fifty-four subjects had a repeat TS in a fasting serum sample with a mean +/- SD TS of 32.1% +/-16.1% (range, 15.4%-63.0%), and 12 donors had a TS > or = 45%. Ten complied with genetic testing and ferritin measurement. The study found four donors with HH-related mutations (C282Y and/or H63D); therefore, a gene allele frequency of 0.4%. Only the C282Y homozygote had diagnostic criteria for HH, defining a disease frequency of 0.1%. None of the donors who were mutations carriers had clinical or laboratory manifestations of organic injury.

We conclude that this is a feasible screening strategy that, by timely diagnosing HH, allows patients not only to benefit from effective treatment but also to have disease progression halted.