title: Study of lymphocyte populations and natural killer activity in severe aplastic anaemia.
abstract: Thirty-one patients (pts) with aplastic anaemia (AA) were studied whose probable etiology were: idiopathic (16 pts), nocturnal aroxysmal haemoglobinuria (NPH) (2 pts), benzene (4 pts), agrotoxics (5 pts), pharmaceutical drugs (2 pts) and insecticides (2 pts). A decrease in total lymphocyte counts was seen in 10 pts belonging mainly to the NPH and pharmaceutical drug groups, whereas, in the benzene group the opposite was found. B cell levels were low in 9 out of 20 pts. T cell levels varied, the majority of patients had normal levels, 13 presented low levels and 4 had increased numbers. CD4 levels were low in 14 pts and T cell numbers were compensated in some by an increase in CD8 cells. Our results show that there is a great heterogeneity among the patients and there might be differences in the immunological profile of aplastic anaemia depending on the causative agent of the disease.
authors.affiliation: Immunology Laboratory, Instituto Nacional de Câncer, Rio de Janeiro, Brazil.
authors.forename: M H
authors.initials: MH
authors.lastname: De Souza
authors.forename: A R
authors.initials: AR
authors.lastname: Pires
authors.forename: H R
authors.initials: HR
authors.lastname: Diamond
mesh_terms: D000328:Adult; D000741:Anemia, Aplastic / Q000139:chemically induced / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D001554:Benzene / Q000506:poisoning; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology; D003602:Cytotoxicity, Immunologic; D006457:Hemoglobinuria, Paroxysmal / Q000150:complications; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology* / Q000473:pathology; D007958:Leukocyte Count; D008214:Lymphocytes / Q000276:immunology* / Q000473:pathology; D010575:Pesticides / Q000506:poisoning; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000473:pathology
chemical_list: D010575:Pesticides; D001554:Benzene