Familial thrombocytosis (FT) is a hereditary disorder probably involving the regulation of megakaryopoiesis. This report is the first documented case of FT in infancy. The clinical course was complicated by a leukaemoid reaction which lasted for several months, in combination with failure to thrive and hepatosplenomegaly. At the age of 5 years the patient, with the exception of thrombocytosis, is healthy and without medication.

We have examined the effect of graft-versus-host disease (GVHD) on the reconstitution of donor hematopoiesis in a murine bone marrow transplant (BMT) model of GVHD to minor histocompatibility antigens. GVHD had no effect on peripheral blood counts, which normalized by 1 month after BMT, and did not affect numbers of hematopoietic progenitors in the BM, which remained decreased in all transplant recipients. Donor stem cells (colony-forming unit-spleen day 8) and stem cell self-renewal remained low in all mice for 5 months after transplant, but GVHD further damaged the stem cell compartment. Peripheral counts 1 month after transplant were supported by increased numbers of stem cells in cycle and increased splenic hematopoiesis. However, GVHD altered the pattern of extramedullary hematopoiesis, causing dramatically decreased activity in the spleen and increased activity in the liver. We conclude that GVHD further decreases hematopoietic reserve and causes damage to the donor stem cell compartment during hematopoietic reconstitution after transplant, despite unaffected progenitor frequencies and peripheral blood counts.

A 5-month-old boy with congenital hypoplastic anaemia and triphalangeal thumbs, known as the Aase syndrome, is described. In addition he had unilateral cleft lip and palate and abnormal dermatoglyphics. Only ten cases have been reported previously; these are reviewed. This case is the third patient reported to have the Aase syndrome who also has a cleft lip. Bone marrow cultures failed to stimulate production of erythropoietic precursors.