Abstract: In systemic lupus eryThematosus (SLE) various antibodies are produced against cells including platelets and result in thrombocytopenia. !n the literature, the incidence of thrombocytopenia varied from 7% to 52%, in seven series of SLE patients with a mean cumulative percentage of 14.5% (1-5 ). SLE patients referred to the Lupus Unit of the Rheumatology Research Center. Tehran University for Medical Sciences. (Shariati Hospital) during the period of 1975 to 1977 ...