Interstitial lung disease (ILD) and severe ITP

Introduction: Platelets play an important role in inflammatory and immune responses. We report interstitial lung disease (ILD) developing during the acute phase of severe thrombocytopenia in 3 patients with severe refractory ITP. Methods and Results: We identified 3 cases with severe ITP who developed ILD in the course of refractory chronic ITP. The thrombocytopenia was severe in all cases. ILD was an incidental finding at the presentation and often misdiagnosed as lung infections. ILD was documented by lung biopsy in cases 1 and 2, supplemented by serial chest X-rays and/or CAT scan. As the ITP improved, ILD regressed in case 1, persisted in case 2, and progressed to advanced pulmonary fibrosis in case 3. Conclusion: We report an association of ILD with severe refractory ITP. ILD was detected in acute phase of platelet destruction, suggesting that platelet destruction may have triggered inflammation in the lung, leading to ILD.