Antiglobulin antibody in the sera of contacts of children with leukaemia.

Healthy adults (parents, neighbours, and hospital staff) in close contact with children with leukaemia were found to have a high incidence of positive latex agglutination antiglobulin tests (probably an IgM antiglobulin antibody). This may explain a previous report of a high incidence of IgM anti-EB virus antibodies in parents of leukaemic children, which our results did not confirm (IgM antiglobulin, reacting with IgG anti-EB virus, could have been misinterpreted as IgM anti-EB virus). The antiglobulin antibody probably represents a nonspecific response to an infective agent. Other hospital staff, including those exposed to nonleukaemic children with infections, had a much lower incidence of the antibody, and it may represent a response to the leukaemic process itself, rather than to the infections to which such children are prone. Some leukaemic children have a similar antibody.

Contact with hospital, drugs, and chemicals as aetiological factors in leukaemia.

45 adults with acute leukaemia or chronic myeloid leukaemia and a control group of patients from the same hospital were asked about the people they had close social contact with before their illness, and about their use of drugs and chemicals. 18 (40%) leukaemia and 6 (13%) control patients had close social contact with hospital personnel or leukaemia patients. 8 (18%) leukaemia patients, but no control patients, had been in close contact with haemotological ward personnel. These differences were statistically significant. 9 (20%) leukaemia and 4 (9%) control patients lived in the same house as healthy persons working in a hospital. No conclusion could be drawn from differences between the two groups in their use of drugs, since the possibility that they were used to treat initial symptoms of leukaemia could not be excluded. Exposure to chemicals, including weed-killers and agricultural insecticides containing a benzene-ring known to be leukaemogenic, was about the same in the two groups.

Leukaemia and lymphoma patients interlinked by prior social contact.

Patients with either leukemia or lymphoma were asked if they had close personal associations with other patients before the onset of disease. Iinitial interviews indicated that several patients could be interlinked into social clusters. Tumour-registry records were used to contact each patient (or a surviving relative) diagnosed during the years 1964-73 in three areas of West Virginia. Close personal associations, antedating the onset of disease in 1 or both individuals of each linkage pair, were detected in 14 of 23 (61%), 14 of 22 (68%), and 6 of 8 (75%) patients from these three areas during this ten-year period. In addition, among 28 randomly selected patients with Hodgkin's disease from various parts of the United States, 10 (36%) had direct or indirect close personal associations with 17 other patients with leukemia or lymphoma. Patients with leukemia or lymphoma frequently are interlinked by prior close personal associations to other patients with these diseases.