Immune-complex disease in mice and humans given C. parvum.

The present studies in mice and cancer-bearing patients, treated with C. parvum (CP) immunotherapy, were to determine the effects of CP on the production of immune complexes (IC) and associated disease. Using the Clq-binding assay, circulating immune complexes were detected in mice given a single high dose of CP (466 microgram) and repeated human-equivalent doses (70 microgram). All mice treated with CP developed proliferative glomerulonephritis, the severity of which was dose-related. The histological and immunofluorescent patterns of the nephritis were those attributed to immune-complex disease. The mice had haematuria but were not in renal failure. Fifty patients with inoperable lung cancer were studied. All received radiotherapy. Twenty-two had no other treatment (controls) and 28 were treated with infusions of CP. Using 2 immune-complex assays (Clq binding and monoclonal rheumatoid-factor binding) IC were found in 10/22 control patients but these did not develop haematuria or proteinuria. Twenty-four of the 28 patients treated with CP developed transient haematuria and/or proteinuria with red-cell and hyaline casts, the changes resolving over 5 days. Immune complexes were detected in 5 of these 28 patients before CP treatment. Although 16/28 had IC at the time of haematuria and proteinuria, these findings were difficult to interpret because IC may occur in response to the tumour, the radiotherapy, or the CP. Although no patient developed renal failure, we believe that those treated with CP should have regular assessment of their renal function.