Cryoglobulinaemia and circulating immune complexes in tropical splenomegaly syndrome.

Large amounts of cryoglobulins and soluble immune complexes were detected in the sera of thirteen patients with tropical spenomegaly syndrome (TSS). Complexes were detected by three different methods: radiobioassay, a modified rheumatoid factor-binding activity method and a modified Clq-binding assay. Protein precipitable by 4% polyethylene glycol (PEG) was also measured. The cryoglobulins contained IgM, IgG and in some cases, C3. It is likely that in TSS, marked immune complex formation is associated with hypergammaglobulinaemia and that continuous engulfment of these complexes by cells of the reticuloendothelial system (RES) is the cause of the hepatosplenomegaly.