Chart — Hematology
DIC Lab Pattern Chart
One story explains every value: the body clots so much it uses up its platelets and factors (so counts fall and clotting times prolong), then breaks those clots down (so D-dimer soars).
Educational use only. Lab interpretation is provider-directed and read in clinical context. 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.
The Pattern
| Lab | DIC result | Why |
|---|---|---|
| Platelets | ↓ Low | Consumed forming widespread microclots |
| Fibrinogen | ↓ Low | Consumed (converted to fibrin clots faster than it's made) |
| PT / INR | ↑ Prolonged | Extrinsic/common clotting factors used up |
| aPTT | ↑ Prolonged | Intrinsic/common clotting factors used up |
| D-dimer | ↑↑ Markedly high | Fibrinolysis breaks down all those clots (key marker) |
| Fibrin degradation products (FDPs) | ↑ High | Breakdown of fibrin clots |
| Peripheral smear | Schistocytes | Red cells sheared as they pass through fibrin-filled vessels |
Reading the Trend
Worsening DIC: platelets and fibrinogen keep falling, PT/aPTT keep rising, D-dimer climbs. Resolving DIC: as the underlying cause is treated, fibrinogen and platelets recover and D-dimer falls. The single most useful DIC marker is a high D-dimer alongside a low/falling fibrinogen and platelet count in a critically ill patient.
Exam Traps
- ✦DIC: ↓platelets, ↓fibrinogen, ↑PT, ↑aPTT, ↑↑D-dimer/FDPs, schistocytes on smear.
- ✦D-dimer is the standout — markedly elevated from breaking down all the microclots.
- ✦Replace what's consumed: platelets, FFP (factors), cryoprecipitate (fibrinogen) when bleeding.
- ✦Treating the trigger (often sepsis) is the definitive therapy — DIC is always secondary.
- ✦Resolution = fibrinogen and platelets rising while D-dimer falls.
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 →