Association of sarcoidosis and immune thrombocytopenia: presentation and outcome in a series of 20 patients.

The association of sarcoidosis and immune thrombocytopenia (ITP) has rarely been investigated. The aim of the current retrospective study was to investigate the clinical and biological phenotypes and outcome of this association in a large series of recent patients. Twenty patients (50% men) were included. Median age at sarcoidosis and ITP diagnosis was 36 (range, 10-83 yr) and 38 (range, 21-83 yr) years, respectively. In 11 of 20 (55%) patients, sarcoidosis onset preceded ITP (median interval, 48 mo; range, 6-216 mo). In 5 of 20 (25%) patients, the 2 conditions occurred concomitantly. In 4 of 20 (20%) patients, ITP onset preceded sarcoidosis (median interval, 68 mo; range, 15-153 mo). In 4 cases, sarcoidosis and ITP were not concomitant, since 1 condition was cured before the other was declared. In 12 of 20 (60%) patients there was a simultaneous onset or relapse of both ITP and sarcoidosis. Sarcoidosis phenotype was characterized by an acute onset in 40% of patients. The visceral involvement included thoracic sites in 19 of 20 (95%) patients and extrathoracic sites in 16 of 20 (80%) patients. At ITP onset, median platelet count was 11 × 10/L (range, 3-90); 17 (85%) patients had a platelet count <30 × 10/L. Seven (35%) patients had a bleeding score >8 without visceral bleeding.Nineteen of the 20 (95%) patients were treated specifically for ITP. After the first-line therapy (prednisone at 1 mg/kg per day for at least 3 consecutive weeks in all patients; with IVIg in addition for 10 patients with severe bleeding score), 12 of 19 (63%) patients achieved a complete response, 6 (31.5%) had a partial response, and only 1 patient failed to respond. At the end of ITP follow-up (median, 70 mo; range, 12-142 mo), 18 (90%) patients achieved a complete response, 1 achieved a partial response, and 1 had no response. After a median follow-up of 105 months, 13 of 20 (65%) patients had persistent sarcoidosis requiring prolonged therapy, and thus sarcoidosis represented the main long-term concern. Main conclusions were 1) ITP presentation was usually severe, but response to treatment was favorable in almost all cases, with no death and no severe bleeding, in contrast with older reports, 2) sarcoidosis was remarkable for the high proportion of cases with an acute onset, a chronic course, and the need for prolonged prednisone therapy, 3) sarcoidosis and ITP onset and evolution were not always synchronous.