T-cell lineage acute lymphoblastic leukemia with chromosome 5 abnormality in a patient with Crohn's disease and lipoid nephrosis.

We describe a 17-year-old patient with a documented history of Crohn's disease (CD) and of minimal-change nephrotic syndrome (MCNS) in whom a diagnosis of T-cell acute lymphoblastic leukemia (ALL) was made. The diagnosis of ALL was established by morphological examination of bone-marrow aspirates and confirmed by means of immunophenotypic analysis showing the involvement of T-cell lineage leukemic cells. The lymphoid clone showed a karyotypic abnormality involving the long arm of chromosome 5 in a translocation (5;6). Few cases of CD complicated by ALL have been previously reported. The present one is the first case combining CD and ALL in a patient with a past history of MCNS. This raises the possibility of a relationship among those diseases. The possible mechanisms for such a relationship are discussed here.