Pure red cell aplasia and lymphoproliferative disorders: an infrequent association.

Pure red cell aplasia (PRCA) is a rare bone marrow failure syndrome defined by a progressive normocytic anaemia and reticulocytopenia without leukocytopenia and thrombocytopenia. Secondary PRCA can be associated with various haematological disorders, such as chronic lymphocytic leukaemia (CLL) or non-Hodgkin lymphoma (NHL). The aim of the present review is to investigate the infrequent association between PRCA and lymphoproliferative disorders. PRCA might precede the appearance of lymphoma, may present simultaneously with the lymphoid neoplastic disease, or might appear following the lymphomatic disorder. Possible pathophysiological molecular mechanisms to explain the rare association between PRCA and lymphoproliferative disorders are reported. Most cases of PRCA are presumed to be autoimmune mediated by antibodies against either erythroblasts or erythropoietin, by T-cells secreting factors selectively inhibiting erythroid colonies in the bone marrow or by NK cells directly lysing erythroblasts. Finally, focus is given to the therapeutical approach, as several treatment regimens have failed for PRCA. Immunosuppressive therapy and/or chemotherapy are effective for improving anaemia in the majority of patients with lymphoma-associated PRCA. Further investigation is required to define the pathophysiology of PRCA at a molecular level and to provide convincing evidence why it might appear as a rare complication of lymphoproliferative disorders.

High prevalence of Helicobacter pylori infection in Greek patients with myelodysplastic syndromes.

BACKGROUND/AIMS/METHODS: To determine the frequency of Helicobacter pylori infection (Hp-I) in 73 patients with myelodysplastic syndromes (MDS) and 40 controls, serologic analyses of Hp and ¹³C-urease breath tests (INFAI) were performed. Gastric mucosal biopsy specimens were obtained to determine the presence of Hp-I using a rapid urease test, i.e. the Campylobacter-like organism (CLO) test, and cresyl violet staining. Peripheral blood (PB) flow cytometry for CD3, CD4, CD8, CD14, CD19 and CD34 was conducted in 35 patients and in controls. RESULTS: Hp-I was detected by: (a) serology in 75.34% of patients (p = 0.000), (b) INFAI in 57.69% of patients, (c) CLO in 60.71% of patients and (d) histological confirmation in 80.36% of patients (p = 0.001). No correlation between Hp-I and CD3, CD4, CD8, CD14, CD19 expression, leukemic transformation or death was observed. However, in 20 cases, significant variation in the PB lymphocytic proportion possibly attributable to Hp-I was ascertained, in contrast to the expected MDS ratio. CONCLUSION: Although there is no evidence for a causal relationship between Hp-I and MDS, the increased prevalence of Hp-I among the MDS patients is an interesting finding that deserves further investigation as it may indicate a common factor causing susceptibilities to both MDS and Hp-I or that Hp might influence the pathophysiology of MDS.

Peripheral blood haematopoietic progenitor cells in patients with beta thalassaemia major receiving desferrioxamine or deferiprone as chelation therapy.

OBJECTIVES: The main adverse effect of deferiprone is the development of neutropenia, which occurs via an unknown mechanism. We aimed to gain insight into the pathogenesis of deferiprone-induced neutropenia by assessing the peripheral blood haematopoietic progenitor cells. METHODS: Sixteen patients with beta thalassaemia were studied; nine (Group A) were receiving desferrioxamine and seven (Group B) deferiprone. Ten healthy individuals comprised the control group (Group C). RESULTS: Granulocyte-erythrocyte-monocyte-megakaryocyte colony forming units were significantly more in Groups A and B compared with Group C. Granulocyte-macrophage colony forming units (CFU-GM) were significantly more in Group B compared with Group C. Macrophage colony forming units were significantly less in Group B compared with Group C. Granulocyte colony forming units (CFU-G) were significantly more in Group A compared with Group C. We found a trend in the difference in the number of CFU-G between patients' groups (P = 0.123). Adding serum from patients receiving deferiprone to cultures of controls resulted in a maturation arrest of the granulocytic lineage. CONCLUSION: Our findings point to a maturation arrest at the level of CFU-GM as a potential mechanism of deferiprone-induced neutropenia.