Chart — Hematology
Thrombocytopenia Comparison Chart
Four causes of low platelets, but the danger differs: ITP bleeds, TTP and HIT clot, and DIC does both. The highest-yield column is the last one — do NOT give platelets in TTP or HIT.
Educational use only. Transfusion decisions and disorder-specific treatment are provider-directed and individualized. This chart is an educational comparison aid. This material supports nursing education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional policy, or medical direction. Always follow facility protocols and current provider orders.
Side by Side
| Disorder | Mechanism | Main danger | Key features | Treatment | Platelet transfusion? |
|---|---|---|---|---|---|
| ITP | Autoantibodies destroy platelets in the spleen | Bleeding | Often post-viral (kids) or chronic (adults); isolated low platelets | Corticosteroids, IVIG, splenectomy | Only for serious bleeding (transfused platelets also destroyed) |
| TTP | ADAMTS13 deficiency → microthrombi (clotting) | Clotting | Pentad: ↓platelets, hemolytic anemia (schistocytes), fever, neuro changes, renal dysfunction | Plasma exchange (plasmapheresis) | AVOID — fuels thrombosis (life-threatening bleeding only) |
| HIT | Anti–heparin-PF4 antibodies activate platelets (clotting) | Clotting | Platelet drop ~5–10 days after heparin; new thrombosis | STOP all heparin; argatroban/bivalirudin/fondaparinux | AVOID — worsens clotting |
| DIC | Systemic clotting consumes platelets AND factors | Both (clot then bleed) | Secondary to sepsis/OB/trauma; ↓fibrinogen, ↑↑D-dimer | Treat the cause; replace products (platelets, FFP, cryo) | Give when bleeding (part of replacement) |
Exam Traps
- ✦TTP and HIT are CLOTTING disorders — do NOT transfuse platelets (it worsens thrombosis).
- ✦TTP pentad → plasma exchange; HIT (~5–10 days after heparin) → stop heparin + argatroban/bivalirudin.
- ✦ITP = immune destruction → steroids/IVIG; platelets only for serious bleeding.
- ✦DIC consumes platelets and factors → treat the cause, replace products when bleeding.
- ✦Always identify the mechanism before assuming low platelets means 'give platelets.'
Related Resources
Standards & sources
Fact-checked Jun 21, 2026This page is written to align with AABB (transfusion standards) · American Society of Hematology (ASH). It is an educational summary, not a citation of any single document — always verify specific doses, values, and protocols against current guidelines and your facility policy. How we source content →