Phylogenetic analyses indicate an atypical nurse-to-patient transmission of human immunodeficiency virus type 1.

A human immunodeficiency virus (HIV)-negative patient with no risk factor experienced HIV type 1 (HIV-1) primary infection 4 weeks after being hospitalized for surgery. Among the medical staff, only two night shift nurses were identified as HIV-1 seropositive. No exposure to blood was evidenced. To test the hypothesis of a possible nurse-to-patient transmission, phylogenetic analyses were conducted using two HIV-1 genomic regions (pol reverse transcriptase [RT] and env C2C4), each compared with reference strains and large local control sets (57 RT and 41 C2C4 local controls). Extensive analyses using multiple methodologies allowed us to test the robustness of phylogeny inference and to assess transmission hypotheses. Results allow us to unambiguously exclude one HIV-positive nurse and strongly suggest the other HIV-positive nurse as the source of infection of the patient.

Karyotype evolution in the bone marrow of a patient with Fanconi anemia: breakpoints in clonal anomalies of this disease.

A 21-year-old Fanconi anemia patient developed refractory anemia. Laboratory studies revealed a transitory increased platelet count and a typical del(5q). Bone marrow karyotyping showed a -6, +der(6)t(1;6)(q12;p25) rearrangement and, two years later, a mosaic -6, +der(6),t(1:6)(q12;p25)/-2, +der 2), t(1;2)(q12;q37) constitution. The chromosome mechanism operating in this patient is discussed.

[Cytogenetic study of acute leukemia]. / Contribution à l'étude cytogénétique des leucémies aiguës.

Chromosome banding techniques have been useful to define abnormal chromosomes in acute leukemia. The comparison between cases reported from different centers has been possible only with the acceptance of a universal system of classification and nomenclature for acute leukemia as well as for chromosomal rearrangements. Chromosomes abnormalities in acute leukemia are found in about 50 per cent of patients. They appear to be non random. Clinical, morphologic and cytogenetic findings have been correlated. Diagnosis and prognosis significance of chromosome abnormalities is of importance. The problem of normal or so called normal cells in 50 per cent of acute leukemia is set.

[Chromosome anomalies in acute lymphoblastic leukemia]. / Les anomalies chromosomiques des leucémies aiguës lymphoblastiques.

Detectable karyotypic changes have been observed in more than 50% of patients with ALL. Distinct nonrandom chromosome abnormalities have been found. Some of these can be correlated with particular parameters such as age, morphology of the blasts, lymphocyte surface markers, prognosis. Karyotype is an important independent prognostic factor in ALL, even when other well-known risk factors are considered but an abnormal clone is not always associated with a poor prognosis. Burkitt leukemia and lymphomas have been shown to present characteristic and specific translocations t(8;14) and variants t (2;8) and t(8;22). It appears that the structural change of chromosome n degree 8 involving band q24 is a consistent chromosome feature in these malignancies, and that this peculiar region on chromosome n degree 8 probably plays an important biological role in the development of these malignant proliferations. The association of cytogenetic and molecular biology techniques would allow in the near future a better understanding of the genesis and significance of chromosome anomalies in malignant blood diseases.

[Introduction to the cytogenetic study of acute leukemias]. / Introduction à l'étude cytogénétique des leucémies aiguës.

Chromosome banding techniques have been useful to define abnormal chromosomes in acute leukemia. The comparison between cases reported from different centers has been possible only with the acceptance of a universal system of classification and nomenclature for acute leukemia as well as for chromosomal rearrangements. Chromosomes abnormalities in acute leukemia are found in about 50 per cent of patients. They appear to be non random. Clinical, morphologic and cytogenetic findings have been correlated. Diagnosis and prognosis significance of chromosome abnormalities is of importance. The problem of normal or so called normal cells in 50 per cent of acute leukemia is set.

[Chromosome anomalies in acute lymphoblastic leukemias]. / Les anomalies chromosomiques des leucémies aiguës lymphoblastiques.

Detectable karyotypic changes have been observed in more than 50% of the patients with ALL, distinct nonrandom chromosome abnormalities have been found. Some of these can be correlated with particular parameters such as age, morphology of the blasts, lymphocyte surface markers, prognosis. Karyotype is an important independent prognostic factor in ALL, even when other well-known risk factors are considered but an abnormal clone is not always associated with a poor prognosis. Burkitt leukemia and lymphomas have been shown to present characteristic and specific translocations t(8;14) and variants t(2;8) and t(8;22). It appears that the structural change of chromosome no 8 involving band q24 is a consistent chromosome feature in these malignancies, and that this peculiar region on chromosome no 8 probably plays an important biological role in the development of these malignant proliferations. The association of cytogenetic and molecular biology techniques would allow in the near future a better understanding of the genesis and significance of chromosome anomalies in malignant blood diseases.