Background: The experimental observation that plasma from TTP patients sometimes exhibits a protein which can cause platelet agglutination, and that such agglutination can be inhibited in vitro by the use of IgG led some authors to treat plasma exchange-resistant TTP patients with high-dose IgG (HDIgG).
Methods: We report the results obtained with HDIgG treatment in 17 patients retrospectively examined by the Italian Cooperative Group for the study of TTP: 6 males and 11 females, mean age was 31.7 years for the women (range: 20-65) and 44.6 for the men (range: 26-66). In all cases HDIgG administration was combined with other treatment modalities.
Results: Of the 17 patients, 7 died from disease progression (41.1%), 2 achieved partial remission (11.7%) and the remaining 8 achieved complete remission (47%). Of the 10 cases (58.8%) with a positive response, only in 4 did the addition of HDIgG seem to produce significant improvement. All efforts made to characterize the subgroup of patients who responded to HDIgG and compare them with the non responders failed.
Conclusions: Although our results do not unquestionably demonstrate the role of HDIgG in the treatment of TTP, they suggest a possible role for HDIgG in the treatment of those rare plasma exchange-resistant TTP cases.