Ristocetin is a new antimicrobial agent consisting of two antibiotics, ristocetin A and B. These components have been separated from the fermentation broth of the actinomycete species Nocardia lurida. Advantages of this drug include the lack of development of resistant organisms and an absence of cross-resistance with other antibiotics. Several investigators have demonstrated the merit of ristocetin in problems of severe staphylococcal and enterococcal infections.1-4
In previous publications5,6 the development of thrombocytopenia in four patients during ristocetin therapy was noted. Platelet depression was related to high doses of ristocetin and could be reversed by discontinuing or reducing the dose. Individuals with renal insufficiency were more susceptible to thrombocytopenia due to drug accumulation.
The purpose of this publication is to report on the subsequent clinical experience and laboratory findings, and to relate these observations to the mechanism and site of action of ristocetin-induced thrombocyto-penia. Five patients have been treated with ristocetin