Familial occurrence of Ivemark syndrome with splenic hypoplasia and asplenia in sibs

Two sibs with Ivemark syndrome are described. This is the fourth observation of familial Ivemark syndrome, while over 200 cases reported in the literature have been sporadic. One of the affected sibs reported here had total absence of the spleen, while a hypoplastic spleen was found in the other sib. The occurrence of splenic aplasia and splenic hypoplasia in the same family would be in support of the unitary concept of Ivemark syndrome. Contrary to previous concepts, Ivemark syndrome with splenic hypoplasia and Ivemark syndrome with splenic aplasia represent variants of one and the same disease entity.