A Survey of the Etiology of Immune Thrombocytopenia (ITP).

Socioeconomic, environmental, lifestyle and genetic factors play a role in the etiology of ITP but are poorly understood. A self-reported questionnaire was designed to study these relationships and how these factors prior to the diagnosis of ITP relate to treatment response and disease progression in order to gain insight into the etiology of ITP.

To design the questionnaire that would address topics of interest: 1) 60 ITP patient interviews were performed and 2) the questionnaire was reviewed by project coordinators, nurse practitioners, Platelet Disorder Support Association (PDSA) members, and hematologists. The input was incorporated into a further-revised questionnaire, which was then administered to both “pediatric” (patients <18 years of age at the time of diagnosis) and adult ITP patients from the Platelet Disorders Center at Weill Cornell - New York Presbyterian Hospital. Formal statistical analysis to relate responses to one question to responses of another to define sub-groups of patients is ongoing.

109 patients were enrolled. Ages ranged from 2–78 years of age; median age was 55 years, with 21 females and 33 “pediatric” patients. The most frequent environmental exposures in adults were automotive exhaust (n=14) and Teflon (n=12). In pediatrics, preservatives and insecticides (n=8) and Teflon (n=7) were most common. The most prevalent hazardous substances in both groups were cleaning supplies (n=16 adults, n=9 “pediatric”) and chlorinated water (n=13 adult, n=9 “pediatric”). 13 adults also had exposure to gasoline or diesel fumes. Refer to figure 1. 51(47%) patients reported at least one infection prior to diagnosis with ITP. The most common were Strep throat (n=12); influenza (n=9), and respiratory tract infections (n=8). Twenty-four (22%) patients reported at least one autoimmune disease, including celiac (n=2) and discoid lupus (n=2).Twenty-one patients reported a family history of Type II diabetes, 12 Type I diabetes, 13 osteoarthritis and 10 rheumatoid arthritis. Eight (7%) patients reported at least one inflammatory disease including: Crohn's disease (n=3), Inflammatory bowel disease (n=7), Systemic lupus erythematous and Vitiligo(each n=1). Thirty-seven (34%) patients reported surgeries prior to diagnosis of ITP, especially: appendectomy (n=8) and tonsil removal (n=8). Twenty-three patients traveled close to date of diagnosis, 58 patients reported more stress than usual (i.e. death of a relative, loss of employment); 13 patients reported a drastic change in diet (i.e. decreasing calories (n=7) or becoming vegetarian (n=5)). Vitamin supplementation for vitamin C and D (each n=17), E (n=12) and B (n=11) were common. In addition, 11 vitamin deficiencies were reported, vitamin D (n=5), vitamin B12 (n=3) and other (n=3). The most frequent allergic reactions included: 31 (28%) patients with hay fever, 9 patients with allergies to milk, 7 patients with poison ivy or skin irritation, 6 patients with eczema, and 4 with allergic rhinitis. Other medical conditions reported were: hypothyroidism (n=10), hyperthyroidism (n=9), high blood pressure (N=16), high cholesterol (N=14), and anemia (N=13) [9 additional patients included 4 with iron deficiency anemia and 5 with a family history of iron deficiency anemia]. Seven patients reported a lack of prenatal care in their mothers' pregnancy and 7 were premature. Medications reported include: acetaminophen (n=53), antibiotics (n=36), antihistamines (n=22), and hormone therapy (n=17). Vaccinations received close to date of diagnosis include: flu vaccine (n=10) and T-dap (n=9). Prednisone was reported most frequently as both the best therapy to minimize symptoms (n=18) and the worst (n=16).

Our pilot study intended to capture critical information and to further development of the questionnaire. We can see if there are groups of patients in whom onset and other characteristics relate to outcomes including response to treatment. Following formal statistical analysis of the material acquired (in progress and anticipated by early September), the next step will be for a final updated version of the questionnaire to be posted on the PDSA web site in order to accrue responses from a much larger number of patients. The questionnaire will also be given to a non-ITP patient population to serve as controls.

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Bussel:Amgen: Family owns Amgen stock Other, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cangene: Research Funding; GlaxoSmithKline: Family owns GSK stock, Family owns GSK stock Other, Membership on an entity's Board of Directors or advisory committees, Research Funding; Genzyme: Research Funding; IgG of America: Research Funding; Immunomedics: Research Funding; Ligand: Membership on an entity's Board of Directors or advisory committees, Research Funding; Eisai: Membership on an entity's Board of Directors or advisory committees, Research Funding; Shionogi: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sysmex: Research Funding; Portola: Consultancy. Off Label Use: The use of romiplostim in pediatric patients was examined in this study.