New diagnostic tool for differentiation of idiopathic hypereosinophilic syndrome (HES) and secondary eosinophilic states

2006 Bethesda International Consensus recommendations on the flow cytometric immunophenotypic analysis of hematolymphoid neoplasia: medical indications

The clinical indications for diagnostic flow cytometry studies are an evolving consensus, as the knowledge of antigenic definition of hematolymphoid malignancies and the prognostic significance of antigen expression evolves. Additionally the standard of care is not routinely communicated to practicing clinicians and diagnostic services, especially as may relate to new technologies. Accordingly there is often uncertainty on the part of clinicians, payers of medical services, diagnostic physicians and scientists as to the appropriate use of diagnostic flow cytometry. In an attempt to communicate contemporary diagnostic utility of immunophenotypic flow cytometry in the diagnosis and follow-up of patients with hematolymphoid malignancies, the Clinical Cytometry Society organized a two day meeting of international experts in this area to reach a consensus as to this diagnostic tool. This report summarizes the appropriate use of diagnostic flow cytometry as determined by unanimous approval of these experienced practitioners.

Peripheral T-cell lymphoma-unspecified (PTCL-U) presenting with hypereosinophilic syndrome and pleural effusions

Hypereosinophilic syndrome (HES) is a clinical disorder characterized by persistent eosinophilia and systemic involvement, in which a specific causative factor for the eosinophilia cannot be verified during a certain period of time. There have been only a few reported cases of this syndrome associated with malignant lymphoma. We report a case of peripheral T-cell lymphoma-unspecified with hypereosinophilic syndrome. The patient was a 42-year-old woman with an uncontrolled fever and a sore throat. Eosinophilia was observed on the peripheral blood smear. We confirmed the diagnosis by bone marrow and liver biopsies:. A bone marrow aspiration demonstrated markedly increased eosinophils (24.8%), and a liver biopsy demonstrated infiltration by scattered eosinophils and atypical lymphoid cells, which were confirmed to be T-cell lymphoma cells. This case was a distinctive presentation of peripheral T-cell lymphoma with hypereosinophilic syndrome, probably due to a paraneoplastic condition.