Prolonged dimethylsulphoxide treatment in 13 patients with systemic amyloidosis.

Continuous oral dimethylsulphoxide (DMSO) treatment (7-15 g/day) was given to 3 patients with amyloidosis of familial Mediterranean fever (FMF), 3 patients with idiopathic amyloidosis, and 7 patients with secondary amyloidosis. The nephrotic syndrome and various degrees of renal insufficiency were the major clinical manifestation in all case. Renal function was used as the main parameter for evaluation of therapy. DMSO treatment for 7-16 months produced no effect in the FMF patients and in the patient with idiopathic amyloidosis; they all ran the predictable clinical course of their disease and either died of cardiac failure or have been maintained on chronic haemodialysis. In the 7 patients with secondary amyloidosis an unequivocal improvement of renal function was observed following 3-6 months of DMSO treatment. It was shown by a 30-100% rise of creatinine clearance and a decline in proteinuria. This new equilibrium has been maintained as long as DMSO was administered. No serious side effects of DMSO wee encountered. Mild nausea and an unpleasant breath odour were the patients' main concern. We conclude that a therapeutic trial with oral DMSO is warranted in all patients with secondary amyloidosis. This treatment is unpleasant but bears no exceptional risks. It may significantly prolong life, though its effect on amyloid deposits themselves is doubtful.