This Medscape article chronicles Eleanor Roosevelt's illness. Eleanor Roosevelt carried a diagnosis of aplastic anemia for two years, for which she received multiple transfusions and was given prednisone. It was not until two weeks before her death that her final bone marrow specimen grew out tuberculosis.
When I was a medical student the story was circulating around that Eleanor Roosevelt had died of miliary Tb that had long been misdiagnosed as aplastic anemia, but I didn't know if it was really true. The Medscape piece, which draws on information from Roosevelt's medical record, is the best account I've found.
This was a popular topic when I was a medical student. One of our most esteemed and feared Internal Medicine mentors, Thomas E. Brittingham, always encouraged skepticism toward accepting any diagnosis of an incurable disease, particularly if an infectious cause could be sought. He was particularly negative about diagnosing patients with idiopathic inflammatory diseases and treating them with immunosuppressives and was fond of presenting patients long diagnosed with such diseases as systemic lupus, Wegener's granulomatosis or inflammatory bowel disease and ultimately discovered to have tuberculosis or a fungal disease.