[Hereditary factors in the etiology of chronic lymphocytic leukemia]

Leukocyte counts, hemoglobin concentration, PAS positivity index in lymphocytes, leukocyte alkaline phosphatase, karyotype, HLA phenotype as wall as the quality of the cellular and humoral immunity have been studied in 45 patients with chronic lymphocytic leukemia (CLL) and in 103 their closest relatives (sibs, parents). The aim was to detect the possible preleukemic condition in the relatives as a strong propensity towards developing has been previously established in families of patients with CLL. In the CLL patients our studies have confirmed the results of the determination of similar parameters by other authors, namely a higher percentage of PAS+ lymphocytes than normal together with a variety of humoral and cellular immunity disturbances. Regarding the morphological and cytochemical changes in lymphocytes in family members of the CLL patients a higher frequency of PAS+ lymphocytes have been observed: it has been established in over 10 per cent lymphocytes (normally 4-8 per cent) in 31 (30%) examinees and in 14 (13.5%) of these persons the percentage of PAS positivity was equal to that found in CLL patients. Cellular immunity examinations established that in one third of examined E rossete counts counts were lower and in 2 persons the degree of this decrease corresponded to the decrease observed in CLL patients. In one fifth of the examined family members T4:T8 ratio was reduced. In the 13 per cent of the examined M rossete counts were increased, a fact which supports the notion that immunity of B cells exists in relatives of CLL patients. The authors contend that the increased percentage of PAS+ lymphocytes and inadequate functional maturity of the T and B cells in a relatively large number of family members of the CLL patients, intimates that a hereditary disturbance in the lymphocyte make up and their role in the immunity pathways exists and could possibly represent one of the factors implicated in a high frequency of CLL in some families.