Myelofibrosis in a Patient with Sarcoidosis.

Abstract

Secondary bone marrow fibrosis can be seen in several conditions such as hematological malignancy, metastatic malignancy and autoimmune disorders like lupus. We report here a 50 year old Middle Eastern female with a history of pulmonary sarcoidosis diagnosed by lung biopsy in January of 2004, beta thalassemia trait, hypertension and hypothyroidism. At the time of diagnosis she was started on bronchodilating inhalers. Nine months later she was referred to hematology for left lower quadrant pain and possible enlarged spleen on examination. CT scan revealed extensive mediastinal, retroperitoneal and inguinal adenopathy but no splenomegaly. Hemoglobin was 12.3 with a hematocrit of 38 and an MCV of 61, WBC was 7.8with a normal differential and Platelet count was 238. Her peripheral blood smear revealed moderate anisocytosis, polychromasia and some teardrops. Bone marrow biopsy showed significant fibrosis confirmed by reticulin staining. Biopsy of an inguinal node was consistent with her lung biopsy showing granulomatous disease. In the course of follow up she developed fever, fatigue, anemia, and splenomegaly proven by ultrasound (16cm). Her labs also revealed increased ACE and ESR levels. We started her on prednisone at 1mg/kg and her hemoglobin rose from 8.0 to 12.5. X-chromosome transcription-based clonality assays were employed to deteremine whether this patient had primary myelofibrosis with myeloid metaplasia, a myeloproliferative disorder characterized by clonal hematopoiesis or secondary myelofibrosis which is characterized by polyclonal hematopoiesis. Six exonic X-chromosome polymorphisms were tested to determine the clonality of the patient's platelets and granulocytes (Liu, BLOOD 2003). Unfortunately, this patient was not informative in any of six exonic X-chromosome polymorphism markers, and we could not determine the clonality of hematopoiesis. Peripheral blood CD34 level; however, was low normal, consistent with reactive fibrosis rather than a primary myeloproliferative disease. To our knowledge this is the first report of secondary bone marrow fibrosis in sarcoidosis.