Lack of HLA-DR expression in a patient with B-chronic lymphocytic leukemia.

We describe a rare case of a patient with chronic lymphocytic leukemia (CLL) whose immunophenotype analysis revealed lack of HLA-DR in B-cells.

A case of HLA-DR negative B-precursor acute lymphoblastic leukemia.

We present the case of a 9-year-old girl from northwestern Greece admitted to our Hospital because of malaise, low-grade fever, intermittent hip joint pain, anemia, leukopenia and thrombocytopenia. The examination of a bone marrow aspirate revealed the predominance of blast cells (97%) with FAB L1 morphology, immunopheno-typically positive for CD19 (95%), CD10 (95%), CD22 (95%), CD13 (82%), CD34 (95%) and CD38 (72%), with dim expression of CD45 and of the intracellular antigen terminal deoxynucleotidyl transferase (Tdt). Only 10% of the blasts expressed HLA-DR. Staining for CD2, CD3, CD5, CD7, CD20, CD23, CD33, CD14, CD15, AC133 and KOR-SA3544 was negative. Blast cells were lacking surface immunoglobulin expression and bcr/abl rearrangements were not detected. Cell cycle analysis revealed a diploid cell population. Karyotypic abnormalities were not identified. The lack of expression of HLA-DR and the presence of myeloid antigen CD13 indicated that it was a rare case of B-precursor ALL with aberrant immunophenotypic characteristics.

Recurrent episodes of deep vein thrombosis in a young man.

We present the case of a 32-year-old man suffering from recurrent episodes of deep vein thrombosis (DVT). He was heterozygous for the G1691A mutation in the Factor V gene. His father was heterozygous for the same mutation and had a unique episode of DVT after a fracture of the tibia. Genetic predisposition significantly influences the prevalence of thrombotic events, however, additional unknown factors may be involved in the initiation and recurrence of venous thromboembolism.

Prevalence of the G20210A prothrombin gene mutation in Northwestern Greece and association with venous thromboembolism.

AIM: The G20210A mutation of the prothrombin gene is a genetic risk factor for venous thromboembolism (VTE). Variability exists in the mutation prevalence in both normal individuals and VTE patients. The aim of this study was to determine the mutation prevalence in Northwestern Greece and evaluate its association with VTE. METHODS: Presence of the G20210A mutation was investigated using DNA analysis in 176 consecutive patients with a history of venous thrombosis or pulmonary embolism and in 300 healthy controls, all Caucasian residents of Northwestern Greece. RESULTS: The mutation was present 12 patients (6.8%) and 8 controls (2.7%). The odds ratio for presence of the mutation versus the normal genotype in VTE was 2.7 (95% CI: 1.1 to 6.7), which was statistically significant. The prevalence of the G20210A prothrombin gene mutation in Northwestern Greece is 2.7% (95% CI: 0.8% to 4.4%) with an allele frequency of 1.3% (95% CI: 0.4% to 2.3%). CONCLUSION: The G20210A mutation of the prothrombin gene is associated with VTE in the Caucasian residents of this geographic region.

Lack of association between the C677T mutation in the 5,10-methylenetetrahydrofolate reductase gene and venous thromboembolism in Northwestern Greece.

BACKGROUND: Hyperhomocysteinemia has been associated with venous thrombosis. Under known and unknown conditions the C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene is accompanied by elevated levels of homocysteine. However, the relationship of this mutation with venous thromboembolism (VTE) remains controversial. The purpose of this study was to evaluate the association of the MTHFR mutation with VTE. METHODS: The presence of the C677T mutation in the MTHFR gene was investigated in a population of 176 consecutive patients with a history of venous thromboembolism and in a control group of 300 healthy subjects, using DNA analysis. RESULTS: The prevalence of homozygosity in the patient group was 13.6% and in healthy subjects 10%. The odds ratio for venous thromboembolism in the presence of the homozygous genotype (677TT) was 1.4 (95% confidence interval (C.I.), 0.8 to 2.5), which was not statistically significant. CONCLUSIONS: Homozygosity for the T677 allele of the MTHFR gene, although slightly more prevalent in patients compared to controls, has not been found in association with venous thromboembolism.