Abstract

A newborn infant with congenital T cell lymphoblastic leukaemia presented with hepatosplenomegaly and pancytopenia at birth and died on the 21st day of multiorgan failure. Biopsy and necropsy examination showed extensive atypical lymphoid infiltrates in the lungs, liver, spleen, kidneys, lymph nodes, and bone marrow. Immunohistochemically, the lymphoid cells were TdT+, CD3+, CD45RO+, and CD10−, CD79a−, CD20−. Genotypic analysis using polymerase chain reaction showed T cell receptor γ chain gene rearrangement and absence of immunoglobulin heavy chain gene rearrangement. This appears to be the first documented case of congenital T cell lymphoblastic leukaemia. The case had unusual histological and immunogenotypic features, disseminated early, and pursued a highly aggressive course. Consideration of the diagnosis is of paramount importance. The immunophenotypic studies and molecular characterisation of such congenital leukaemias are critical in arriving at a definite diagnosis.