Immunophenotypic analysis of bone marrow B lymphocyte precursors (hématogones) by flow cytometry.

The aims of this flow cytometry study were to quantify B lymphoid precursors known as hématogones across age and clinical conditions and to study the immunophenotypic profile of these benign immature B cells. A total of 406 consecutive marrow specimens were analyzed for hématogones using 4-color flow cytometry during a 19 month period (60% males and 40% females). The age range was 3 months to 89 years. Hématogones were present in 80% of the specimens. Morphologic analysis of the smears from each patient showed small numbers of hématogones (<13% of total cellularity). The B cell population was defined by CD19 + CD45 bright positivity, coexpression of other B lineage markers: CD20, CD22, CD10, CD29, CD38 and CD58 in addition to HLA-DR and CD34. In our study we found a significant decline in hématogones with increasing age but a broad range was found at all ages. Marrow from some adults contained relatively high numbers. Diagnosis in these patients included cytopenias, infections, and neoplastic diseases. Distinction of hématogones is critical for disease management particularly after therapy of paediatric B acute lymphoblastic leukaemia to monitor for minimal residual disease.

[Haematological characteristics, FAB and WHO classification of 153 cases of myeloid acute leukaemia in Tunisia]. / Caractéristiques hématologiques et classification FAB et OMS de 153 cas de leucémies aiguës myéloïdes en Tunisie.

A complete blood analysis with a careful morphologic examination of peripheral blood and bone morrow smears completed by cytochemical reaction will help to classify the most acute myeloid leukaemia (AML). Actually, the study of other cytogenetis and immunophenotypic markers are now necessary to confirm diagnosis. The World Health Organisation WHO classification (2001) incorporates theses approaches. The purpose of this study is a bio-clinical review according to the WHO recommendations in 153 cases of LAM diagnosed between January 1998 and December 2003. The patients were aged 2 months to 90 years with sex ratio (M/F) of 1,22. The morphologic conclusion was difficult in 12% cases. Presence of dysplasia is noted in 50% of cases with multilineage dysplasia in 42% of cases. Our results showed cloned chromosomal abnormalities in 57% of cases (t(8;21): 12%, t(15;17) : 10%, Inv16: 1,3%, 11q23: 2,6% et complex karyotype: 14,3%). In 69% of cases with multilineage dysplasia, the karyotype was normal. 3 cases of LAM were noted at patients treated for breast cancer with chirurgic chemotherapy and radiotherapy 3, 4 et 5 years after treatment (LAM3 with t(15;17), LAM4 with genetic abnormalities of chromosomes 3, 5, 7, 8, 9, 14 et 16 et LAM 6 with genetic abnormalities of chromosomes 4, 7, 12, 14, 19 et 21). In WHO classification, cytology is essential in diagnosis of LAM even if the karytype have an important prognostic value. Research of signs of dysplasia lineage after lineage constitutes an important microscopic work and it is difficult to quantify dysplasia when the lineage is poor.

Identification of the translocation t(15;17) in acute myeloid leukemia (AML) initially classified as FAB M1: case report and review of the literature.

We report a case of a patient aged about 53 years, who initially presented with hematological disorders (WBC: 44000/mm3, Hb: 11g/dl, Pit: 127000/mm3) without tumoral syndrome. The Wright-Giemsa stained bone marrow and peripheral blood smears showed a population of blast cells characterized by cells with high N/C and strongly basophilic cytoplasm without granules. The nuclei were predominantly round. Nuclear chromatin was fine and contained small nucleoli. Cytochemisty was positive for peroxidase activity. Immunophenotyping showed myeloid typical markers of granulocytic lineage (MP0+, CD13+, CD33+, CD117+, CD34-). The karyotype revealed the expression of t(15;17) chromosomal translocation. The diagnosis of acute myeloid leukaemia (AML) was then evoked initially. The cytological features corresponded closely to the M1 subtype as defined in the FAB classification. The patient was treated with induction therapy according to the 7/3 protocol. One month later, he was discharged from hospital on hematological and cytogenetic remission. He died at home because of a heart attack. From the biological findings the patient was retrospectively diagnosed as having promyelocytic leukemia (hyperbasophilic form).

[Antiphospholipid antibodies in 146 women with repeated pregnancy losses]. / Anticorps antiphospholipides et pertes foetales: étude rétrospective de 146 cas.

Antiphospholipid antibodies are associated with arterial and venous thrombosis and recurrent abortions. However, the prevalence of these antibodies in repeated miscarriages varies in different reports. To obtain quantitative data with restricted criteria and discuss the origin of the variability on the literature, we investigated the presence of antiphospholipid antibodies in 146 women who had 2 or more consecutive pregnancy losses and in 99 women whose pregnancies were successful. Antiphospholipid antibodies (lupus anti-coagulant or anticardiolipin antibodies of 20 or more IgG units) were found in 45% of women with pregnancy losses and in 9% of controls (p < 0.001). The type of loss was determined according to the trimester of pregnancy and the time of the fetal loss. 68% of patients with antiphospholipid antibodies had at least one fetal loss on the second or third trimester compared with 45% of patients without fetal loss (p < 0.01). Further studies should be conducted using more rigorous definition of clinical and laboratory characteristics in a way to allow better comparison between studies.