Long-term outcome of haematopoietic stem cell transplantation in autosomal recessive osteopetrosis: an EBMT report

A retrospective analysis was made of 122 children who had received an allogeneic haematopoietic stem cell transplantation (HSCT) for autosomal recessive osteopetrosis between 1980 and 2001. The actuarial probabilities of 5 years disease free survival were 73% for recipients of a genotype HLA-identical HSCT (n = 40), 43% for recipients of a phenotype HLA-identical or one HLA-antigen mismatch graft from a related donor (n = 21), 40% for recipients of a graft from a matched unrelated donor (n = 20) and 24% for patients who received a graft from an HLA-haplotype-mismatch related donor (n = 41). In the latter group, a trend towards improvement was achieved at the end of the study period (17% before 1994, 45% after 1994, P = 0.11). Causes of death after HSCT were graft failure and early transplant-related complications. Severe visual impairment was present in 42% of the children before HSCT. Conservation of vision was better in children transplanted before the age of 3 months. Final height was related to height at the time of HSCT and better preserved in children transplanted early. Most children attended regular school or education for the visually handicapped. At present, HSCT is the only curative treatment for autosomal recessive osteopetrosis and should be offered as early as possible.