[A case of idiopathic hypercalcemia (hypersensitivity to vitamin D 3].

Hypercalcaemia occurs in two forms: mild and severe. In the mild form, usually in young infants the characteristic signs of the severe from (Williams syndrome) are absent, and thus it may cause diagnostic difficulties. Because of that, in infants with muscular hypotonia, growth arrest, constipation and apathy the possibility of idiopathic hypercalcaemia, apart from rickets, should be considered.