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shwachmann - diamond syndrome ( sds ) is a rare autosomal recessive disorder characterized by exocrine pancreatic insufficiency , somatic abnormalities ( particularly metaphyseal dystosis ) and bone marrow dysfunction .
it was first described in 1964 by shwachman et al . and is now recognized as the second most frequent cause of pancreatic insufficiency in children .
in addition , myelodysplastic syndrome and acute myeloid leukemia ( aml ) have been recognized as major complications in this disease and occur in up to one third of patients .
when leukemia develops , due to the preceding bone marrow failure , serious complications may be induced by chemotherapy and underlying organ dysfunctions . at present , the only curative treatment option for bone marrow dysfunction and leukemia in sds is allogeneic bone marrow transplantation ( bmt ) .
we report the first case in korea of a patient with sds to undergo related bmt following transformation to aml .
a 21-year - old woman was admitted to the hospital because of indigestion and poor oral intake .
she was pancytopenic ( hb 9.7 g / dl white cell count of 4,200/l [ neutrophils 800/l ] and platelets 220,000/l ) .
marrow aspirate showed high cellularity with massive infiltration by blast cells which were positive for sudan black and myeloperoxidase ( figure 1 ) .
the blast population displayed the following immunophenotype : cd13 48% , cd33 59% , cd34 61% , hla - dr 59% and cd20 negative .
a complex karyotype was found in 20 out of 20 metaphases : 47xx , del ( 20)(q11.2 ) , tas ( 21;22 ) ( q22;q13 ) , + 22 ( figure 2 ) .
the abdominal mri showed an enlarged pancreas , a hyperintense signal on t1-and t2-weighted image and low signal on fat - suppressed image ( figure 3a , b ) .
the period of aplasia was characterized by numerous complications , including persistent fever despite empiric antibacterial and antifungal therapy and hematemesis .
unmanipulated donor marrow was given following conditioning with cyclophosphamide ( 60 mg / kg2 ) and total body irradiation ( tbi ) ( 1200 cgy in 6 fractions ) using a combination of cyclosporin a and methotrexate as graft - versus - host disease ( gvhd ) prophylaxis .
the post - transplant period was complicated by staphylococcal septicemia and acute gvhd in grade ii .
but she has been alive disease free and off any immunosuppressives , for a follow - up of 13 months after bmt .
sds is an inherited constitutional bone marrow failure syndrome and has a marked propensity of developing leukemia . in a recent study
, the overall risk of malignant transformation was found to be 24% , while leukemia was observed in 70% of a subgroup of patients with pre - existing pancytopenia , myelodysplastic features and clonal cytogenetic abnormalities .
one patient died from congestive heart failure attributed to cyclophosphamide toxicity as part of the conditioning regimen .
although a similar cyclophosphamide dose was used in the patient reported here , no cardiac dysfunction was observed in the pre- and post - bmt period .
our observations indicate that a cyclosphosphamide / tbi conditioning regimen might be taken into consideration in patients with sds .
the unspecific cytogenetic abnormalities are a common finding in sds and were detected in about 40% of patients in an earlier study .
this led to the hypothesis that sds might also be a chromosomal breakage syndrome caused by a dna repair defect . and
also , constitutional karyotype of our patient was abnormal : 47xx , del ( 20 ) ( q11.2 ) , tas ( 21;22 ) ( q22;q13 ) , + 22 .
as the same with other cases of acute leukemia in patients with sds , the clinical course of the disease in our patient was characterized by multiple complications after chemotherapy , and by a delayed hematologic reconstitution .
although the correct clinical approach for leukemic sds patients is still to be determined , our case shows that a stable remission may be obtained by allogeneic bmt , even in the presence of an adverse complex bone marrow karyotype .
shwachman - diamond syndrome ( sds ) is a rare genetic disorder of unknown pathogenesis involving exocrine pancreatic insufficiency and hematological and skeletal abnormalities . 
 about 25% of patients develop hematopoietic malignancies . 
 we report on a case of acute myeloid leukemia ( m2 ) in a 21-year - old woman affected by sds . 
 she was treated with conventional chemotherapy ( idarubicin plus cytarabine ) and reached complete remission of leukemia . 
 after induction chemotherapy , she underwent allogeneic bone marrow transplantation ( bmt ) . 
 the bmt preparative regimen consisted of total body irradiation ( tbi ) followed by cyclophosphamide . 
 cyclosporin a and short term methotrexate were used for graft - versus - host disease prophylaxis . after a follow - up of 12 months , she is alive leukemia free off any immunosuppressive agent . 
 although experience in this field is scarce , we speculate that bone marrow failure in sds is an indication for bmt which is the only curative treatment option .