Spontaneous Resolution of ITP in Two Elderly Patients.
Authors: Andersson Karin L. , Warth James A. 
Published: April 2020

Abstract
Because adult idiopathic thrombocytopenic purpura (ITP) is often a prolonged illness with a high risk of major bleeding, guidelines have advocated immediate treatment of low platelet counts in such adults. We describe two elderly ITP patients with minor bleeding whose platelet counts normalized spontaneously within three months, raising the possibility that select adult ITP may not require treatment. The first patient is an 83 year old female who experienced spontaneous bruising with a platelet count of 5000/mm3. She had no significant medical history, did not drink alcohol or take medications known to cause thrombocytopenia, but did have a recent viral illness. Her peripheral blood smear showed scant platelets without clumping, microcytic but not hypochromic red cells, and no helmet cells or schistocytes. A bone marrow aspirate and biopsy revealed moderately increased megakaryocytes, mild dysplasia and reduced but present bone marrow iron stores. Without a change in medications or therapy for ITP, the platelet count rose to 20,000 overnight. The platelets were 46,000 at one week, normalized in three months, and remain stable at 226,000 three years later. The course was similar for a second patient, a 72 year old female who presented with painless hematuria, purpura and petechiae due to a platelet count of 9000/mm3. She had no medical history or antecedent viral illness, did not drink alcohol, and did not take thrombocytopenia-causing medications. The other cell lines and a peripheral blood smear were normal. Bone marrow examination revealed a hypocellular (20%) marrow with mild dysplasia and increased megakaryocytes. Without treatment, the platelets rose to 28,000 overnight and to 42,000 within 48 hours. The platelet count was 176,000 on day 5, 202,000 by day 82 and 202,000 at 21 months. Continuous improvement in the platelet level, measured initially every 8 to 12 hours, was characteristic of these two patients who received no therapy. In light of the hemorrhagic risks of ITP, the American Society of Hematology recommends urgent treatment of adults with platelet counts lower than 20,000, or less than 50,000 with significant mucus membrane bleeding. A consequence of these recommendations is that the outcome of untreated disease is unknown (George et al, 1996). Although adult ITP is often characterized by chronically depressed platelets, resistance to therapy, and a significant risk of hemorrhagic complications, a small percent of adult disease may be caused by an antecedent viral infection and be characterized by spontaneous recovery of platelet counts (Neylon et al, 2002). Prior to the routine use of corticosteroids for ITP, some individuals had spontaneous remission while awaiting splenectomy (Watson-Williams et al, 1958). In these cases platelets rose within two weeks and normalized within one hundred days. The risk of bleeding and mortality of acute ITP is lower than in chronic disease (Cortelazzo et al, 1991). Like children, a subset of adults may have a self-limited form of ITP with a low risk of bleeding that does not require treatment. In a study of chronic ITP, more patients died from therapeutic complications than from bleeding in the setting of thrombocytopenia (Portielje et al, 2001). As the incidence of ITP rises with the aging population, the risk and benefits of treating all adult patients must be considered.