Síndrome de hiperviscosidad como presentación de la macroglobulinemia de waldenström: Reporte de caso / Waldenström's macroglobulinemia presenting as hyperviscosity syndrome. Case report

La Macroglobulinemia de Waldenström (MW) es una neoplasia hematológica infrecuente, caracterizada por presentar gammapatía monoclonal de IgM e infiltración linfoplasmocítica en la médula ósea. Representa cerca del 1-2% de las neoplasias malignas hematológicas y es importante diferenciarla de otros procesos linfoproliferativos como la gammapatía monoclonal de significado incierto (MGUS) y de otros trastornos asociados a IgM.Suele debutar con síntomas inespecíficos, o ser un hallazgo de laboratorio, pudiendo presentar malestar general, astenia, baja de peso, o bien un cuadro poco frecuente producido por el aumento de la concentración de IgM sérica, denominado síndrome de hiperviscosidad. Éste corresponde a una urgencia hematológica que debe ser tratada precozmente ya que conlleva consecuencias graves para el paciente. Reportamos el caso de una mujer de 64 años con antecedente de MGUS IgM que progresa a Macroglobulinemia de Waldenström con síndrome de hiperviscosidad, presentado manifestaciones clínicas inespecíficas que al inicio minimiza, pero que conlleva a lesiones retinianas extensas. Dado la gravedad del cuadro, requiere manejo con plasmaféresis en unidad de paciente crítico.

Waldenström's macroglobulinemia is an infrequent hematological neoplasm characterized by Ig M monoclonal gammopathy and lymphoplasmacytic infiltration of the bone marrow. It accounts for 1-2% of malignant hematological neoplasms and it is important to distinguish it from other lymphoproliferative disorders such as monoclonal gammopathy of undetermined significance and other disorders involving IgM. It usually presents with non-specific symptoms, or is a laboratory finding, and may present as general malaise, weakness, weight loss or, rarely, hyperviscosity syndrome caused by a rise in the levels of circulating IgM. This is a hematological emergency which must be treated at once as it can have serious consequences for the patient. We report a case of a 64 year old woman with previously diagnosed monoclonal gammopathy of undetermined significance who progressed to Waldenström´s macroglobulinemia with hyperviscosity syndrome and minimal non-specific clinical signs which led to extensive retinal lesions. Given the seriousness of her condition she was treated with plasmapheresis in Intensive Care.

Progress of myeloid differentiation factor 88 L265P mutation in B-cell proliferative neoplasms / 白血病·淋巴瘤

Myeloid differentiation factor 88 (MYD88) is a key linker in the Toll-like receptor (TLR) signaling pathway, which plays an important role in the progression of the tumour. Recent studies have shown that the activating mutation of MYD88 L265P has been identified in about of 90% lymphoplasmacytic lymphoma/Waldenstrom's macroglobulinemia and about of 40% diffuse large B-cell lymphoma and other subtypes of B-cell proliferative neoplasms. Different types of B-cell proliferative neoplasms have their own histology, immunohistochemistry and clinical characteristics, thus, mutation rates of MYD88 L265P are different. This review discusses the latest progress of MYD88 L265P mutation in B-cell proliferative neoplasms.