# DIC Score Calculator (ISTH Overt DIC)

URL: https://speedycalculator.com/calculators/health/dic-syndrome/
Last updated: 2026-10-30

> The DIC score calculator applies the International Society on Thrombosis and Haemostasis criteria for overt disseminated intravascular coagulation – platelet count, D-dimer or fibrin markers, prothrombin time and fibrinogen.

## Inputs

- Platelet count
- D-dimer / fibrin-related marker
- Prolonged prothrombin time
- Fibrinogen

## Results

- ISTH DIC score
- Interpretation

## Formula

```
Score = sum of the points for each item
```

## Explanation

DIC is a life-threatening state of widespread clotting and bleeding triggered by sepsis, trauma, cancer or obstetric emergencies. The ISTH score should only be used when an underlying disorder known to cause DIC is present. A score of 5 or more is compatible with overt DIC; repeat daily.

### How to use the DIC Score Calculator

- **Platelet count**
- **D-dimer / fibrin-related marker**
- **Prolonged prothrombin time**
- **Fibrinogen**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Each answer carries the points shown in the published score. The calculator adds them up and maps the total to the published interpretation.

### Scoring table

ItemAnswers and pointsPlatelet countOver 100 ×10⁹/L = 0; 50–100 ×10⁹/L = 1; Under 50 ×10⁹/L = 2D-dimer / fibrin-related markerNo increase = 0; Moderate increase = 2; Strong increase = 3Prolonged prothrombin timeUnder 3 seconds = 0; 3–6 seconds = 1; Over 6 seconds = 2FibrinogenOver 1 g/L = 0; 1 g/L or less = 1

### Inputs explained

FieldWhat to enterPlatelet countChoose one: Over 100 ×10⁹/L, 50–100 ×10⁹/L, Under 50 ×10⁹/LD-dimer / fibrin-related markerChoose one: No increase, Moderate increase, Strong increaseProlonged prothrombin timeChoose one: Under 3 seconds, 3–6 seconds, Over 6 secondsFibrinogenChoose one: Over 1 g/L, 1 g/L or less
*Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.*

## Worked example

Inputs — Platelet count: 50–100 ×10⁹/L; D-dimer / fibrin-related marker: Moderate increase; Prolonged prothrombin time: 3–6 seconds; Fibrinogen: Over 1 g/L.

Results — **ISTH DIC score = 4 / 8**; Interpretation = Not suggestive of overt DIC – repeat in 1–2 days.

## Key terms

- **DIC**: Disseminated intravascular coagulation.

## FAQ

**When should the DIC score be used?**
Only when a condition known to cause DIC is present.

**What is overt DIC?**
A score of 5 or more.

**How is DIC treated?**
By treating the cause, with blood products for bleeding when needed.


## Sources

- [Taylor FB Jr et al. Towards definition, clinical and laboratory criteria, and a scoring system for DIC (ISTH). Thromb Haemost, 2001](https://pubmed.ncbi.nlm.nih.gov/11816725/)