A single Centre Experience with allogeneic Stem Cell Transplantation for Severe Aplastic Anaemia in Childhood

Abstract BACKGROUND Severe aplastic anaemia (SAA) is a rare disorder which has a fatal course when allogeneic stem cell transplantation (SCT) or an immunosuppressive regimen is not applied. Stem cell replacement is the only curative approach for these patients but it is limited by the availability of a compatible donor. PATIENTS Between 1982 and 1993, 18 children (15 boys, 3 girls) with SAA and HLA identical, MLC negative donors underwent SCT in our institution. SAA was preceded by viral infection in 8 patients (3 × hepatitis, 1 × measles, 1 × herpes simplex infection and 3 × viral upper respiratory tract infections). It was drug-associated in one and idiopathic in the 9 others. The median age at diagnosis was 9.7 years (range, 2 months to 16 years). Pretreatments included corticosteroids in 11/18 patients, androgens in 4 patients in addition, two had received cyclosporin A (CSA). One patient progressing from Diamond- Blackfan anaemia to SAA had multiple immunosuppressive treatment courses over 7 years before his grand-uncle was identified as donor while 4 patients had no treatment prior to SCT. METHODS Early SCT (within 90 days after diagnosis) was performed in 9/18 patients and the median interval between diagnosis and SCT was 2,6 months (range, 0.5 to 7 years). The stem cell source was the bone marrow (BM) of a syngeneic twin in 2 patients, the BM (13 patients) or the cord blood (1 patient) of a sibling whilst it was BM from a HLA-phenotypic family donor (1 father, 1 granduncle) in two patients. Cyclophosphamide 50 mg/kg on 4 consecutive days was given as preparative regimen to 16 patients but not to the two syngeneic twins. Rejection prophylaxis included total lymphoid irradiation in 5/16 patients while in the other 11 patients donor buffy coat cells were given on days +1 to +4. The syngeneic twins had no need for either approach. Patients received a median number of 3,7 x 10 8 /kg nucleated cells (range, 2.6 to 6.7). Prophylaxis of graft versus host disease (GVHD) was carried out with MTX alone (n = 12), with CSA alone (n = 2) or with both (n =4). All patients received standard supportive care. RESULTS The overall survival is 89% at the median observation time of 100 months. The median time to reach 500 granulocytes was 24 days (range, 15 to 40). Median time to become transfusion independent after BMT was 30 days for platelets (range, 2 to 111) and was 28 days for packed red blood cells (range, 6 to l28). Acute GVHD was observed in 10/18 patients and