[Three cases of idiopathic thrombocytopenic purpura showing an increase in the platelet count following clarithromycin treatment].

Macrolides have immuno-modulatory effects as well as anti-bacterial effects. We successfully treated three idiopathic thrombocytopenic purpura (ITP) patients with clarithromycin (CAM). Case 1: A 69-year-old male ITP patient was treated with CAM at a dose of 400 mg/day. His platelet count increased from 5.6 x 10(4)/microliter to 10.1 x 10(4)/microliter. Case 2: A 72-year-old male ITP patient was treated with CAM at the same dose. The platelet count increased from 1.3 x 10(4)/microliter to 12.3 x 10(4)/microliter. Case 3: A 68-year-old female ITP patient was treated with CAM at the same dose. The platelet count increased from 2.3 x 10(4)/microliter to 13 x 10(4)/microliter. These facts suggest that CAM is useful in the treatment of ITP.