Rheumatoid factors in Salmonella and Schistosoma infections

Rheumatoid serum factors (anti-globulin antibodies) were studied in chronic salmonella bacteriaemia associated with schistosomiasis, in acute typhoid and paratyphoid fevers, and in schistosomiasis. Rheumatoid factor existed in high frequency and high titre among patients with either chronic or acute salmonella infection, and in high frequency and low titre among patients with schistosomiasis. Following successful treatment of salmonella infections, titres of rheumatoid factor fell. 2-mercaptoethanol consistently eliminated completely the titres of rheumatoid factors, indicating that all were probably IgM. Similar complete elimination of salmonella somatic antigen agglutinins was observed in sera of some patients with either chronic or acute salmonella infection. This association of rheumatoid factors with chronic bacterial and helminthic infections is not unexpected. However, similar results in acute typhoid and paratyphoid fevers necessitate a review of the pathogenesis of IgM anti-globulin antibodies associated with infections.