Familial benign copper deficiency: an old case re-examined.

Seven years follow-up and re-examinations of a boy and his mother with "familial benign copper deficiency" revealed repeatedly subnormal serum copper and normal caeruloplasmin levels with relatively good psychosomatic development in the 9-year-old index patient. 64Cu-uptake was elevated in the mother's and normal in the proband's fibroblasts. The pathomechanism of the condition remained unknown, but the biochemical findings and the clinical course did not correspond to any of the previously described forms of congenital defects of copper metabolism.