ITP (Immune Thrombocytopenia) – GCCNurseJobs.com Clinical Guide

Pathophysiology

ITP = immune-mediated destruction of platelets by autoantibodies (predominantly anti-GPIIb/IIIa). Platelets are opsonised and destroyed by macrophages in the spleen and liver. Concurrent impairment of platelet production from megakaryocytes by T-cell mediated destruction.

Diagnosis = Exclusion

Isolated thrombocytopenia (other cell lines normal)
No other cause identified
Exclude: H. pylori, HIV, HCV, SLE, APS, drug-induced (heparin, quinine, NSAIDs)
Blood film: large platelets (young); no schistocytes (rules out TTP/HUS)

Platelet Count & Bleeding Risk

Platelet Count	Bleeding Risk	Clinical Management
>50 × 10⁹/L	Low	Observe; may not need treatment
30–50 × 10⁹/L	Moderate	Treat if symptomatic or surgery planned
10–30 × 10⁹/L	High	Treatment required
<10 × 10⁹/L	Very High — ICH risk	Urgent treatment; IVIG + platelets if active bleeding

Secondary Causes to Exclude

H. pylori

Test all new ITP patients. Eradication alone can improve platelet count in 50% of H.pylori-positive ITP. Urea breath test or stool antigen preferred.

HIV & HCV

Screen all new ITP patients. HIV-associated ITP responds to HAART. HCV treatment can improve platelet count.

SLE / APS

ANA, anti-dsDNA, antiphospholipid antibodies. SLE is a common secondary cause of ITP, especially in young women.

Drug-Induced

Heparin (→ HIT), quinine, NSAIDs, antibiotics. Review all medications. Stop offending drug.

Treatment Ladder

First-Line: Prednisolone 1 mg/kg/day

Start for symptomatic patients or platelet <30 × 10⁹/L. Response in 70–80%. Taper after 3–4 weeks. Dexamethasone 40 mg × 4 days is an alternative (faster onset).

Emergency: IVIG 1 g/kg

For acute severe bleeding, pre-surgery, or platelet <10 × 10⁹/L. Rapid platelet rise (24–48h) but transient effect (2–4 weeks). Does not change long-term outcome. Very expensive.

Chronic ITP: TPO Receptor Agonists

Romiplostim (SC weekly injection) and eltrombopag (oral daily). Stimulate platelet production. High response rate. Continued indefinitely if effective. Second-line after failed steroids.

Rituximab

Anti-CD20 monoclonal antibody. 375 mg/m² IV × 4 weekly doses. Response rate ~60% but durable responses in only ~20%. Before considering splenectomy.

Splenectomy — Last Resort

Removes main site of platelet destruction and autoantibody production. 70–80% response. Lifelong risk of overwhelming post-splenectomy infection (OPSI). Vaccinate 2 weeks before: pneumococcal, meningococcal, Hib. Lifelong penicillin prophylaxis.

HIT vs ITP — Critical Distinction

HIT = Heparin-Induced Thrombocytopenia — THROMBOSIS, not bleeding

Anti-PF4 antibodies activate platelets → paradoxical thrombosis. 4Ts score: Thrombocytopenia, Timing (5–10 days after heparin start), Thrombosis, no oTher explanation. Management: STOP ALL HEPARIN immediately and start argatroban (or fondaparinux/danaparoid). Never give platelets in HIT.

Feature	ITP	HIT
Main risk	Bleeding	Thrombosis
Antibody	Anti-GPIIb/IIIa	Anti-PF4/heparin complex
Treatment	Steroids, IVIG, TPO agonists	STOP heparin + argatroban

GCC Context

H. pylori Prevalence — Eradication Improves Platelets

H. pylori infection is highly prevalent in GCC countries (40–70%). All ITP patients should be screened for H. pylori. Eradication alone can result in significant platelet improvement in H.pylori-positive ITP patients, potentially avoiding immunosuppression. Test with urea breath test or stool antigen (serology unreliable post-treatment).

SLE-Related ITP in Middle East/Asian Populations

SLE is more common and more severe in Middle Eastern and South Asian populations compared to Europeans. SLE-associated ITP is therefore more prevalent in GCC's diverse population. Always exclude SLE in young women with ITP. Screen with ANA, anti-dsDNA, complement levels.

Pre-splenectomy vaccination is mandatory in GCC hospitals. Required vaccines: Streptococcus pneumoniae (Pneumovax/Prevenar), Neisseria meningitidis (ACWY + B where available), Haemophilus influenzae type b. Give 2 weeks before elective splenectomy. If emergency splenectomy: vaccinate 2 weeks post-op. Lifelong penicillin V prophylaxis and medical alert card required.

IVIG is available across GCC but is extremely expensive. Coverage varies by health insurance. Government healthcare (e.g., MOH Saudi Arabia, SEHA Abu Dhabi) generally covers IVIG for ITP. Private insurance may require pre-authorisation. Nurses should be aware of the approval process in their institution.

Key Exam Points

ITP = anti-GPIIb/IIIa antibodies; isolated thrombocytopenia; exclusion diagnosis
Platelet <10 = very high ICH risk; emergency treatment required
First-line: prednisolone 1 mg/kg/day
IVIG for emergency — rapid but transient (2–4 weeks)
TPO receptor agonists: romiplostim, eltrombopag — for chronic ITP
Splenectomy = last resort; vaccinate 2 weeks before (pneumo/mening/Hib)
HIT = thrombosis NOT bleeding; STOP all heparin + argatroban
H. pylori eradication can improve platelets in H.pylori-positive ITP

Practice MCQs

1. A patient with ITP has a platelet count of 8 × 10⁹/L with active purpura. Initial management should include:

2. A patient develops thrombocytopenia 7 days after starting unfractionated heparin for DVT prophylaxis. There is a new DVT in the contralateral leg. This presentation is most consistent with:

3. Before elective splenectomy for chronic ITP, the patient must receive vaccines against:

4. Which oral TPO receptor agonist is used for chronic ITP refractory to steroids?

Immune Thrombocytopenia (ITP)