Esplenomegalia familiar como manifestación clínica del síndrome linfoprolifetativo autoinmune / Familial splenomegaly as a first clinical sign of autoimmune lymphoproliferative syndrome

Introducción: El síndrome linfoproliferativo autoinmune es la consecuencia de un defecto genético que compromete la apoptosis de los linfocitos. La linfoproliferación se manifiesta por adenomegalias y/o esplenomegalia crónica. El diagnóstico requiere demostrar el defecto de la apoptosis linfocitaria y el aumento de linfocitos T dobles negativos (TDN) que carecen de CD4 y CD8. Existe riesgo de desarrollar linfomas y enfermedades autoinmunes, sobre todo citopenias. Métodos: Estudiamos a un niño de 14 años con esplenomegalia de varios años de evolución con antecedentes familiares de esplenomegalia y adenomegalias. Se analiza el fenotipo de los linfocitos T y el defecto molecular del gen TNFRSF6 en el niño, su hermana y el padre. Se estudia el defecto de la apoptosis en el niño y su padre. Resultados: En el niño y su padre se confirman el defecto de la apoptosis de los linfocitos, el aumento de linfocitos dobles negativos (el 18 y 5%, respectivamente) y la misma mutación del gen TNFRSF6. La hermana presenta la misma mutación con un 16% de linfocitos doblemente negativos. Comentarios: La esplenomegalia crónica familiar puede ser la única manifestación del síndrome linfoproliferativo autoinmune (AU)

Background: The autoimmune lymphoproliferative syndrome (ALPS) is caused by genetic defect in lymphocyte apoptosis. Chronic lymphadenopathy and splenomegaly are the consequence of lymphoproliferation. The diagnosis is based on the assessment of the defective lymphocyte apoptosis and the identification of lymphocyte T subset that are double negative (CD4-CD8-). The susceptibility to lymphoma and autoimmune diseases, mainly blood cytopenias is increased. Methods: We studied a 14 year-old boy with chronic splenomegaly and familial history of splenomegaly and lymphadenopathy. T lymphocyte phenotypes, and molecular defect of TNFRSF6 gene were studied in the child, his sister and his father. Lymphocyte apoptosis was also analysed in the child and his father. Results: The boy and his father showed in vitro apoptosis defects, an increased number of double negative T lymphocytes (18% and 5%, respectively) and the same mutation in the TNFRSF6 gene. His sister had 16% of double negative T lymphocytes and the mutation in the TNFRSF6 gene. Comments: Chronic familial splenomegaly can be the only clinical sign of autoimmune lymphoproliferative syndrome (AU)

[Familial splenomegaly as a first clinical sign of autoimmune lymphoproliferative syndrome]. / Esplenomegalia familiar como manifestación clínica del síndrome linfoprolifetativo autoinmune.

BACKGROUND: The autoimmune lymphoproliferative syndrome (ALPS) is caused by genetic defect in lymphocyte apoptosis. Chronic lymphadenopathy and splenomegaly are the consequence of lymphoproliferation. The diagnosis is based on the assessment of the defective lymphocyte apoptosis and the identification of lymphocyte T subset that are double negative (CD4-CD8-). The susceptibility to lymphoma and autoimmune diseases, mainly blood cytopenias is increased. METHODS: We studied a 14 year-old boy with chronic splenomegaly and familial history of splenomegaly and lymphadenopathy. T lymphocyte phenotypes, and molecular defect of TNFRSF6 gene were studied in the child, his sister and his father. Lymphocyte apoptosis was also analysed in the child and his father. RESULTS: The boy and his father showed in vitro apoptosis defects, an increased number of double negative T lymphocytes (18% and 5%, respectively) and the same mutation in the TNFRSF6 gene. His sister had 16% of double negative T lymphocytes and the mutation in the TNFRSF6 gene. COMMENTS: Chronic familial splenomegaly can be the only clinical sign of autoimmune lymphoproliferative syndrome.