[Hereditary hemochromatosis: phenotypic study in a Spanish population]

Hereditary hemochromatosis (HH) displays an important phenotypic variability and is a disease influenced by many factors.

We included 88 patients with HH. Main clinical and laboratory data were analyzed, and the influence of 6 variables on intensity of iron overload was evaluated.

In 38.6% (95% confidence interval [CI], 28.5-49.6%) patients, none of the typical symptoms of the disease was observed. 30,9% (95% CI, 21.7-41.7%) showed abnormalities of the glucose metabolism. We detected an increase in sideremia in 75.0% patients (CI 95%, 64.4-83.3%), transferrin saturation index (TSI) in 95.4% (CI 95%, 88.1-98.5%) and ferritin in 93.2% (CI 95%, 85.1-97.1%) of patients. In addition, we observed increased values of GPT and alkaline phosphatase in an appreciable percentage of patients. Ferritin was significantly higher in men (1329.4 [913.2] ng/ml vs 656.6 [644.5] ng/ml; p < 0.001), and in those older than 45 years (1293.9 [1006.9] ng/ml vs 868.9 [642.8] ng/ml; p = 0.023] and in not blood donors (1205.2 [926.8] vs 524.8 [365.9] ng/ml; p < 0.001). TSI was 81.9% (19.6) in C282Y homozygotes and 65.7% (19.2) in the rest of HFE genotypes (p = 0.002). Differences of TSI with regard to sex, age or status of blood donor were not detected. Sideremia was significantly higher in patients infected by virus C (251.8 [24.4] microg/dl vs 182.8 [45.8] microg/dl; p = 0.001).

HH patients have a noticeable phenotypic variability, and for that reason clinical symptoms are only orientative for the diagnosis. The relationship between HH and glucose metabolism should be investigated further. Iron parameters can be influenced by age, sex, HFE genotype, blood donation, alcohol intake and hepatitis C virus infection.