Miliary Tuberculosis Associated with Chronic Neutrophilic Leukemia

We report a case of miliary tuberculosis associated with chronic neutrophilic leukemia (CNL). A 70-yearold woman was referred to our hospital complaining of a 1-month history of persistent fever and anorexia. Chest and abdominal computed tomography images revealed diffuse small nodular lesions in the bilateral lung fields and extreme splenomegaly. Sputum cultures isolated Mycobacterium tuberculosis. After antituberculous therapy for 1 year, the patient underwent splenectomy for massive splenomegaly and progressive leukocytosis. The presence of the homozygous JAK2 V617F tyrosine kinase mutation was also demonstrated in the peripheral blood. She was finally diagnosed as having miliary tuberculosis associated with CNL based on the histopathological examination of spleen. The patient was treated with a daily dose of 500 mg of hydroxyurea. As a result, 18 months after the splenectomy, her leukocyte count was decreased and her clinical condition was markedly improved; there was no relapse of the CNL.