Remission of Lymphocytic Interstitial Pneumonia in Sjögren’s Syndrome after Autologous Peripheral Blood Stem Cell Transplantation

Interstitial pneumonia occurs in approximately 25% of patients with primary Sjögren's syndrome. Interstitial pneumonia combined with primary Sjögren's syndrome usually responds well to systemic steroids, and fatal cases are rare. Lymphocytic interstitial pneumonia shows diffuse infiltration of polyclonal B and T cells. Autologous stem cell transplantation is performed in cases of primary Sjögren's syndrome as an optional treatment when the condition responds poorly to conventional treatment. The hypothesis that primary Sjögren's syndrome improves after transplantation relies on the role of B-cell abnormalities in pathogenesis or the strong effects of immunosuppressive therapy. We experienced the case of a patient diagnosed with primary Sjögren's syndrome and lymphocytic interstitial pneumonia progression refractory to conventional treatment (steroid and immunosuppressive drugs) and cyclophosphamide pulse therapy. Our patient demonstrated improvement of lung manifestations and autoimmune disease activity after autologous stem cell transplantation.