Rituximab for managing acquired hemophilia A in a case of chronic neutrophilic leukemia with the JAK2 kinase V617F mutation.

Background: Acquired hemophilia A is rarely found in association with myeloproliferative neoplasms, such as the JAK2 kinase V617F mutation-positive chronic neutrophilic leukemia (CNL).

Case Report: An 80-year-old Japanese male was diagnosed with acquired hemophilia A. He had compartment-like symptoms due to soft tissue hemorrhage in his left forearm and right lower extremity.

Validation of the revised 2008 WHO diagnostic criteria in 75 suspected cases of myeloproliferative neoplasm.

The objective of this study was to validate the recently revised 2008 WHO diagnostic criteria of myeloproliferative neoplasms (MPN) together with the analysis of correlation of JAK2 (Janus kinase 2)-V617F mutant allele burden with clinical/laboratory findings on each patient. We made a diagnosis of 75 suspected MPN patients based on both diagnostic criteria of the 2001 WHO classification and the revised 2008 WHO classification, and found that both criteria show a quite similar diagnostic power except for two patients (idiopathic erythrocytosis (IE) and thrombocytosis) who were diagnosed as essential thrombocythemia by the 2008 WHO criteria. From JAK2-V617F analysis, hemoglobin and hematocrit values were significantly higher and platelet count was lower in JAK2-V617F high allele burden group than JAK2-V617F middle allele burden group.