[Etiology of the cribra orbitalia: effect of amino acid profile in bone collagen and the iron content of bone minerals].

As long as cribra orbitalia manifests itself as an isolated skeletal lesion in excavated human skeletons, it is mostly diagnosed as being of nutritional origin, especially iron deficiency anemia. Since both iron and vitamin C function as cofactors at the hydroxylation of the amino acids proline and lysine in collagen, both amino acid analyses of bone collagen and the determination of bone mineral iron content was carried out at ten medieval skeletons with cribra orbitalia, opposed to ten morphologically healthy individuals from the same skeletal series. The skeletons with cribra orbitalia were significantly depleted with respect to OHpro (the OHpro/Pro-ratio being 16.9% lower than in the control group), but did not differ from the healthy individuals with respect to OHlys and iron content. No correlation was found between proline hydroxylation and age at death or degree of the disease. The data do not support the iron deficiency hypothesis. Most probably, vitamin C deficiency was responsible for the difference between diseased and morphologically healthy individuals. A combination of protein and elemental analysis of excavated bones should thus be suitable for the detection of deficient hydroxylation and its etiology: iron or vitamin C deficiency.