Implementation of flow cytometry in the diagnostic work-up of myelodysplastic syndromes in a multicenter approach: report from the Dutch Working Party on Flow Cytometry in MDS.

Flow cytometry (FC) is recognized as an important tool in the diagnosis of myelodysplastic syndromes (MDS) especially when standard criteria fail. A working group within the Dutch Society of Cytometry aimed to implement FC in the diagnostic work-up of MDS. Hereto, guidelines for data acquisition, analysis and interpretation were formulated.

[Monoclonal B-cell lymphocytosis: physiological entity or preliminary stage of chronic lymphocytic leukaemia?].

The criteria for the diagnosis of chronic lymphocytic leukaemia (CLL) have recently been changed, with the absolute number of monoclonal B cells instead of the total number of lymphocytes now important. CLL is diagnosed when the number of monoclonal B cells with the characteristic CLL phenotype in peripheral blood exceeds 5 x 10(9)/l; fewer than 5 x 10(9)/l of monoclonal B cells with the characteristic CLL phenotype present in peripheral blood leads to a diagnosis of monoclonal B-cell lymphocytosis (MBL): a new diagnostic entity. The prevalence of MBL is estimated to be 3% and has a relatively mild course with a progression rate from MBL to CLL of 1-2% per year.

Differences in residual white blood cell subset counts in buffy coat-depleted red cell concentrates prepared with bottom and top or quadruple-bag systems.

Background: For preparation of buffy coat-depleted red cell concentrates (RCCs) in additive solution whole blood is currently collected in The Netherlands both in quadruple-bag and bottom and top bag systems. By using the quadruple-bag system both plasma and buffy coat cells are transferred into integrated satellite bags while the red cells remain in the collection bag. When bottom and top bags are used, the buffy coat remains in the collection bag while both red cells and plasma are transferred into satellite bags.

Platelet activation in the Dutch haemocytometry quality assessment programme: correlation between P-selectin expression and variation in platelet count.

Since 1990, our laboratory has prepared a set of 8 fresh whole blood samples for use in a countrywide quality assessment (QA) programme. The samples are intended as external controls for haemocytometry analysers. These samples are of 8 different haematocrit levels and each one is prepared from a single donor.

Regulation of iron metabolism in the acute-phase response: interferon gamma and tumour necrosis factor alpha induce hypoferraemia, ferritin production and a decrease in circulating transferrin receptors in cancer patients.

Background: The acute-phase response and anaemia of chronic disease are characterized by hypoferraemia associated with an increased ferritin synthesis, which might be mediated by the activated cytokine cascade.

Methods: We examined the prolonged effects of isolated limb perfusion (ILP) with recombinant human tumour necrosis factor alpha (rTNF), recombinant human interferon gamma (rIFN-gamma) and melphalan on interleukin (IL) 6 and acute-phase protein levels, iron status and serum transferrin receptor (sTfR) levels in 12 patients with melanoma or sarcoma. Patients were treated with ILP during 90 min after pretreatment with rIFN-gamma during 2 days.