H. pylori: CagA antigen mimics platelet GPIIIa; eradication improves platelets in 50–60%
HIV, HCV, HBV, CMV, EBV all associated with secondary ITP via immune dysregulation
Diagnosis criteria
Platelet count <100 x 10³/μL
No other identifiable cause of thrombocytopenia
Diagnosis of exclusion
Therapeutic Considerations
Treatment goal hierarchy
Not to normalize platelet count but to achieve safe platelet count to prevent bleeding
Target platelet count >30 x 10³/μL for most non-bleeding patients
Target >50 x 10³/μL for minor invasive procedures
Target >80 x 10³/μL for major surgery or neuraxial anesthesia
Mechanism-based therapy selection
Corticosteroids: block Fc-receptor-mediated phagocytosis; reduce antibody production
IVIG: saturate Fc receptors; increase platelet survival (transient)
Anti-D: opsonizes Rh-positive RBCs to compete for Fc receptors in spleen
Rituximab: depletes B cells; reduces autoantibody production
TPO-receptor agonists: stimulate megakaryopoiesis to overcome peripheral destruction
Fostamatinib: Syk kinase inhibitor; blocks Fc-receptor signaling for platelet destruction
Splenectomy: removes primary site of platelet destruction and autoantibody production
ASH 2019 Guideline key recommendations
Observation preferred over treatment for platelets >30 x 10³/μL without bleeding
Prednisone or dexamethasone as first-line pharmacotherapy
TPO-receptor agonists preferred over rituximab for second-line therapy
Splenectomy deferred until at least 12 months from diagnosis
Patient Discharge Instructions
copy discharge instructions
What is ITP?
ITP (Immune Thrombocytopenic Purpura) is a condition where your immune system attacks and destroys your blood platelets
Platelets are needed to form clots and stop bleeding
This can cause bruising, tiny red spots on the skin (petechiae), and abnormal bleeding
Your medications
Take all prescribed medications as directed
If prescribed prednisone or dexamethasone, do not stop suddenly without talking to your doctor
Avoid aspirin, ibuprofen, naproxen, and other NSAIDs — these thin the blood further
Avoid alcohol — it can lower your platelet count further
If taking eltrombopag, take on an empty stomach; avoid dairy, calcium, iron, or antacids within 4 hours before or 2 hours after
Activity and safety
Avoid contact sports, rough play, or activities with high fall or injury risk while platelets are low
Wear protective headgear for any activity with head injury risk
Use a soft toothbrush and electric razor to minimize cuts
Consider wearing a medical alert bracelet
Follow-up appointment
Return to your hematologist or doctor within 24–72 hours for a repeat blood test
Bring a list of all your current medications to every appointment
Return immediately to the Emergency Department if you experience
Sudden severe headache, confusion, vision changes, or weakness (possible brain bleed)
Blood blisters in your mouth (wet purpura)
Nosebleed that does not stop with 20 minutes of continuous pressure
Blood in urine or stool, or vomiting blood
Heavy or prolonged menstrual bleeding
Dizziness, fainting, or feeling very weak
Significant new bruising much worse than your baseline
References
Guidelines and key sources
Cooper N, Ghanima W. Immune Thrombocytopenia. N Engl J Med. 2019;381:945–955
Comprehensive review of ITP pathophysiology, diagnosis, and management
Neunert C, Terrell DR, Arnold DM, et al. American Society of Hematology 2019 Guidelines for Immune Thrombocytopenia. Blood Advances. 2019;3(23):3829–3866
ASH evidence-based guideline on diagnosis, treatment thresholds, and therapy selection
Chowdhury SR, Sirotich E, Guyatt GH, et al. Guideline on the Emergency Management of Critical Bleeding in Patients With Immune Thrombocytopenia. Blood Advances. 2026
Gauer RL, Whitaker DJ. Thrombocytopenia: Evaluation and Management. Am Fam Physician. 2022;106(3):275–285
Practical primary care approach including differential diagnosis and disposition
Jones DE, Walker JJ, Abellada AMP. Hematologic Emergencies: Recognition and Initial Management. Am Fam Physician. 2024
Emergency recognition and management of thrombocytopenic emergencies
Additional references
DeSouza S, Angelini D. Updated Guidelines for Immune Thrombocytopenic Purpura: Expanded Management Options. Cleve Clin J Med. 2021;88(12):680–689
Updated management including TPO-receptor agonists and fostamatinib
Shimano KA, Grimes AB, Kaicker S, et al. Eltrombopag for Newly Diagnosed Pediatric Immune Thrombocytopenia Requiring Treatment. JAMA. 2025
Pediatric ITP eltrombopag efficacy and safety trial
ACOG Practice Bulletin No. 207. Thrombocytopenia in Pregnancy. Obstet Gynecol. 2019;133(3):e181–e193
Guidance on distinguishing gestational thrombocytopenia from ITP in pregnancy
Pishko AM, Li A, Cuker A. Immune Thrombotic Thrombocytopenic Purpura. JAMA. 2025
Differentiating TTP from ITP; ADAMTS13 testing and management
Witkowski M, Witkowska M, Robak T. Autoimmune thrombocytopenia: Current treatment options in adults with a focus on novel drugs. Eur J Haematol. 2019;103(6):531–541
Second-line treatment options including fostamatinib and novel TPO-RAs
Kashiwagi H, Kuwana M, Murata M, et al. Reference Guide for the Diagnosis of Adult Primary Immune Thrombocytopenia, 2023 Edition. Int J Hematol. 2024
Japanese consensus diagnostic criteria and updated adult ITP reference guide
SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.