Tropical hypergammaglobulinaemia and tissue antibodies

High prevalence of polyclonal hypergamma-globulinemia in adult males in Ghana, Africa

Chronic antigenic stimulation is associated with hypergamma-globulinemia. Higher rates of hypergamma-globulinemia in tropical populations are maintained even with migration to temperate regions. We conducted a population-based screening study to assess the prevalence and risk factors for hypergamma-globulinemia in Ghana, Africa. 917 Ghanaian males (50-74 years) underwent in-person interviews and health examinations. Serum from all persons was analyzed by electrophoresis performed on agarose gel; serum with a discrete/localized band was subjected to immunofixation. 54 persons with monoclonal proteins were excluded and 17 samples were insufficient for analysis. Using logistic regression and Chi-square statistics we analyzed patterns of hypergamma-globulinemia. Among 846 study subjects, the median γ-globulin level was 1.86 g/dL. On the basis of a U.S. reference, 616 (73%) had hypergamma-globulinemia (>1.6 g/dL) and 178 (21%) had γ-globulin levels >2.17 gm/dl. On multivariate analyses, lower education status (P = 0.0013) and never smoking (P = 0.038) were associated with increased γ-globulin levels. Self-reported history of syphilis was associated with hypergamma-globulinemia. We conclude that three quarters of this population-based adult Ghanaian male sample had hypergamma-globulinemia with γ-globulin levels >1.6 g/dL. Future studies are needed to uncover genetic and environmental underpinnings of our finding, and to define the relationship between hypergamma-globulinemia, monoclonal gammopathy of undetermined significance (MGUS), and multiple myeloma.

Survival patterns in patients with Hodgkin's lymphoma with a pre-existing hospital discharge diagnosis of autoimmune disease

PURPOSE

Autoimmune diseases (AIs) are associated with elevated risk for Hodgkin's lymphoma (HL); however, information on the interplay of AIs and HL on survival is sparse.

PATIENTS AND METHODS

We evaluated survival patterns for 7,414 patients with HL in relation to a pre-existing hospital discharge diagnosis of an AI. We also assessed survival patterns in relation to a prior AI diagnosis among 29,240 population-based matched controls.

RESULTS

Among female patients with HL with (v those without) a pre-existing AI, the 5-year and 10-year overall survival was 46.0% (63.3%) and 41.0% (51.9%); for males, the corresponding numbers were 48.5% (59.2%) and 43.6% (51.5%), respectively (P < .001). Among female controls with (v those without) a pre-existing AI, the 5-year and 10-year overall survival was 79.1% (90.2%) and 67.2% (83.3%); for males, the corresponding numbers were 82.5% (90.3%) and 68.6% (81.6%), respectively (P < .001). Female patients with HL with (v those without) a pre-existing AI had a 1.8-fold (range, 1.3- to 2.4-fold) increased relative risk of dying at 5 years of follow-up; for males, the corresponding excess relative risk of dying was 1.7-fold (range, 1.3- to 2.2-fold).

CONCLUSION

Patients with HL have an overall excellent outcome from treatment but also pose some of the most complex challenges of cancer survivorship due to many late effects (eg, second malignancies, thyroid disease, cardiovascular disease, and altered reproductive and sexual function). Our finding that patients with HL with a hospital discharge diagnosis of an AI have a substantially higher risk of dying, emphasizes that underlying chronic diseases, such as AIs, should be high of the list of survivorship concerns for clinicians that treat HL.

Tropical rheumatology. Immunological aspects

The presence of auto-antibodies in infectious diseases continues to puzzle and provoke. It is hoped that sequencing studies in particular will yield further clues as to the role and mechanism of production of autoantibodies in infectious diseases. This, in turn, may also provide further insights into the role of auto-antibodies in auto-immune diseases. From a practical clinical viewpoint, the search for improved auto-antibody tests and new diagnostic markers with improved sensitivity and specificity must continue in the tropics. Until this is achieved, the results of auto-antibody tests in persons living in the tropics, persons from the tropics or patients with tropical infections, must be interpreted with caution.

Autoantibodies in malaria, tuberculosis and hepatitis B in a west African population

Following reports of associations between autoantibodies and living in the tropics, we have studied the seroprevalence and nature of anti-nuclear antibodies, anti-cardiolipin antibodies, antibodies to extractable nuclear antigens and anti-neutrophilic cytoplasmic antibodies in 351 West Africans with malaria, tuberculosis or hepatitis B, or in good health. Amongst healthy West Africans we found a seroprevalence of 7% for anti-nuclear antibodies with several staining patterns, and of 30.3% for anti-cardiolipin antibodies. Among patients with tuberculosis and malaria there was twice that frequency of anti-nuclear antibodies (predominantly speckled in pattern), and anti-neutrophil cytoplasmic antibodies (predominantly IgM) were demonstrated in a few cases. A possible association between IgG anti-cardiolipin antibodies and tuberculosis was observed (P < 0.05), but antibodies to double-stranded DNA were not elevated and no antibodies to extractable nuclear antigens were found in any of the patients or healthy individuals studied. Our findings suggest the need for caution in the interpretation of autoantibody tests in subjects from or living in the tropics, as well as in patients with tropical infections.

Heterologous reactions involving parasites, blood group antibodies and tissue components

The sera of many patients with malaria and filariasis, and also anti-A and B blood group sera, were found to react by immunofluorescence with the somatic musculature of nematodes, especially Ascaris, and human and rat muscle, especially the skeletal type. These reactions were attributed to a polysaccharide related to AB substance in adult nematodes and to raised AB antibodies in malaria. Similar heterologous reactions were found to involve the integument of schistosome adult worms and the microfilariae of Loa loa, which were attributed to the incorporation of host AB blood group substances into the parasite. Other parasites and sera gave mainly negative results. These heterologous reactions constitute a potential hazard in immunofluorescence tests, against which skeletal muscle provides a control. The antibodies concerned were not operative in complement fixation tests, but there was a relationship to anti-complementary activity which suggested the transient presence of a circulating antigen.