The visual system in thrombotic thrombocytopenic purpura.

Thrombotic thrombocytopenic Purpura (TTP) is a rare, acute usually fatal disease of unknown cause. As the name indicates, it is typified by the abnormal rate of platelet consumption with the deposition of thrombi in many vessels. Approximately 300 cases of TTP have been described in the literature since the first report by Moschowitz in 1925. It may occur at any age, but the peak incidence is during the third decade. Females are affected more frequently than males in the ration 3:2. TTP has occurred in siblings and in a husband and wife. It has been associated with pregnancy in 24 cases. "Visual changes" have been reported in 8% of cases; however, the nature of these visual changes has not been elucidated. It is the purpose of this report to call the attention of ophthalmologists to the severe involvement of the visual system which may occur. We will illustrate with a case report one cause of the blurred vision in TTP, and illustrate other ways the visual system may be involved with a review of the pertinent literature.