Lymph node infection by Trichomonas tenax: Report of a case with co-infection by Mycobacterium tuberculosis

In an 82-year-old woman, presenting with fever and asthenia, cervical adeno pathy was noted. Clinical and radiological investigations were fruitless. L aboratory examinations detected a refractory anemia. The lymph node was exc ised and showed numerous trichomonads on touch preparations. Histologically , the node showed caseous necrosis and macrophagic reaction. Diagnosis of l ymph node infection by Trichomonas tenax was made. Three weeks later, cultu re of the node showed Mycobacterium tuberculosis and let us conclude co-inf ection, T tenax is usually regarded as a harmless saprophyte of the oral ca vity, This exceptional observation shows for the first time an invasive pot ential of T tenax. It raises questions about links with tuberculosis and re fractory anemia. HUM PATHOL 31:1317-1321. Copyright (C) 2000 by W.B. Saunde rs Company.