What are the limitations of the french ttp score?

While the french ttp score is highly validated, it should not replace clinical judgment. OpiCalc provides the latest evidence-based limitations for the french ttp score to ensure safe bedside use and optimal diagnostic accuracy.

How does the french ttp score compare to other Hematology scores?

The french ttp score is a gold-standard diagnostic tool. OpiCalc provides side-by-side clinical guidance to help clinicians choose the most specific evidence-based tool for their patient's presentation.

Is the french ttp score free to use?

Yes. OpiCalc provides the french ttp score completely ad-free and optimized for mobile bedside use, ensuring you can calculate medical risk swiftly and without distraction.

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French TTP Score

TTP Signature: Differentiates TTP from HUS. TTP typically presents with extreme thrombocytopenia and remarkably preserved renal function.

Platelets (×10^9/L)

Threshold: < 30

Creatinine

Threshold: < 200

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Differentiating Thrombotic Thrombocytopenic Purpura (TTP) from other Thrombotic Microangiopathies (TMAs) like HUS.

Predicting severe ADAMTS13 deficiency (< 10%) when lab results are not immediately available.

Aiding the decision to initiate emergency Plasma Exchange (PEX).

The Emergency Pivot

TTP is a medical emergency with >90% mortality if untreated. If the clinical suspicion is high and the score is positive, proceed to PEX without waiting for ADAMTS13 levels.

Section 2

Formula & Logic

Coppo et al. Framework

Variable	Threshold / Criteria
Platelet Count	< 30 × 10⁹/L
Serum Creatinine	< 200 µmol/L (≈ 2.26 mg/dL)
Schistocytes	Must be present for TMA diagnosis

Interpretation

If both criteria (Plt < 30 AND Creat < 200) are met: PPV for TTP is 94%.

If neither met: TTP is highly unlikely; consider alternative TMA or HUS.

Section 3

Pearls/Pitfalls

French vs. PLASMIC

The French score is simpler and more specific than the 7-item PLASMIC score. It relies on the classic TTP "signature" of severe thrombocytopenia with preserved renal function—a pattern rarely seen in HUS or DIC.

Section 4

Evidence Appraisal

Primary Consensus

Predictive factors for severe acquired ADAMTS13 deficiency in idiopathic thrombotic thrombocytopenic purpura.

Coppo P et al. • Journal of Thrombosis and Haemostasis. 2010;8(2):224-30.

View Source

Section 5

Literature

History

Developed by the French Reference Center for Thrombotic Microangiopathies using a large registry of patients with TMA, specifically aiming for the highest positive predictive value for TTP.

Last Comprehensive Review: 2026

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Differentiating Thrombotic Thrombocytopenic Purpura (TTP) from other Thrombotic Microangiopathies (TMAs) like HUS.

Predicting severe ADAMTS13 deficiency (< 10%) when lab results are not immediately available.

Aiding the decision to initiate emergency Plasma Exchange (PEX).

The Emergency Pivot

TTP is a medical emergency with >90% mortality if untreated. If the clinical suspicion is high and the score is positive, proceed to PEX without waiting for ADAMTS13 levels.

Section 2

Formula & Logic

Coppo et al. Framework

Variable	Threshold / Criteria
Platelet Count	< 30 × 10⁹/L
Serum Creatinine	< 200 µmol/L (≈ 2.26 mg/dL)
Schistocytes	Must be present for TMA diagnosis

Interpretation

If both criteria (Plt < 30 AND Creat < 200) are met: PPV for TTP is 94%.

If neither met: TTP is highly unlikely; consider alternative TMA or HUS.

Section 3

Pearls/Pitfalls

French vs. PLASMIC

Section 4

Evidence Appraisal

Primary Consensus

Predictive factors for severe acquired ADAMTS13 deficiency in idiopathic thrombotic thrombocytopenic purpura.

Coppo P et al. • Journal of Thrombosis and Haemostasis. 2010;8(2):224-30.

View Source

Section 5

Literature

History

Developed by the French Reference Center for Thrombotic Microangiopathies using a large registry of patients with TMA, specifically aiming for the highest positive predictive value for TTP.

Last Comprehensive Review: 2026

Related Hematology Tools

England & Fraser Index

Shine & Lal Index

Corrected Reticulocyte Count

Transferrin Saturation Calculator

Iron Deficit Calculator

HFE Haemochromatosis Risk Estimator

Hepatic Iron Index

DAT Interpretation Algorithm

Coombs-Negative Haemolysis Checklist

PLASMIC Score

Have feedback about this calculator?Let us know.

French TTP Score

TTP Signature: Differentiates TTP from HUS. TTP typically presents with extreme thrombocytopenia and remarkably preserved renal function.

Platelets (×10^9/L)

Threshold: < 30

Creatinine

Threshold: < 200

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Differentiating Thrombotic Thrombocytopenic Purpura (TTP) from other Thrombotic Microangiopathies (TMAs) like HUS.

Predicting severe ADAMTS13 deficiency (< 10%) when lab results are not immediately available.

Aiding the decision to initiate emergency Plasma Exchange (PEX).

The Emergency Pivot

TTP is a medical emergency with >90% mortality if untreated. If the clinical suspicion is high and the score is positive, proceed to PEX without waiting for ADAMTS13 levels.

Section 2

Formula & Logic

Coppo et al. Framework

Variable	Threshold / Criteria
Platelet Count	< 30 × 10⁹/L
Serum Creatinine	< 200 µmol/L (≈ 2.26 mg/dL)
Schistocytes	Must be present for TMA diagnosis

Interpretation

If both criteria (Plt < 30 AND Creat < 200) are met: PPV for TTP is 94%.

If neither met: TTP is highly unlikely; consider alternative TMA or HUS.

Section 3

Pearls/Pitfalls

French vs. PLASMIC

Section 4

Evidence Appraisal

Primary Consensus

Predictive factors for severe acquired ADAMTS13 deficiency in idiopathic thrombotic thrombocytopenic purpura.

Coppo P et al. • Journal of Thrombosis and Haemostasis. 2010;8(2):224-30.

View Source

Section 5

Literature

History

Developed by the French Reference Center for Thrombotic Microangiopathies using a large registry of patients with TMA, specifically aiming for the highest positive predictive value for TTP.

Last Comprehensive Review: 2026

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Differentiating Thrombotic Thrombocytopenic Purpura (TTP) from other Thrombotic Microangiopathies (TMAs) like HUS.

Predicting severe ADAMTS13 deficiency (< 10%) when lab results are not immediately available.

Aiding the decision to initiate emergency Plasma Exchange (PEX).

The Emergency Pivot

TTP is a medical emergency with >90% mortality if untreated. If the clinical suspicion is high and the score is positive, proceed to PEX without waiting for ADAMTS13 levels.

Section 2

Formula & Logic

Coppo et al. Framework

Variable	Threshold / Criteria
Platelet Count	< 30 × 10⁹/L
Serum Creatinine	< 200 µmol/L (≈ 2.26 mg/dL)
Schistocytes	Must be present for TMA diagnosis

Interpretation

If both criteria (Plt < 30 AND Creat < 200) are met: PPV for TTP is 94%.

If neither met: TTP is highly unlikely; consider alternative TMA or HUS.

Section 3

Pearls/Pitfalls

French vs. PLASMIC

Section 4

Evidence Appraisal

Primary Consensus

Predictive factors for severe acquired ADAMTS13 deficiency in idiopathic thrombotic thrombocytopenic purpura.

Coppo P et al. • Journal of Thrombosis and Haemostasis. 2010;8(2):224-30.

View Source

Section 5

Literature

History

Developed by the French Reference Center for Thrombotic Microangiopathies using a large registry of patients with TMA, specifically aiming for the highest positive predictive value for TTP.

Last Comprehensive Review: 2026

Related Hematology Tools

England & Fraser Index

Shine & Lal Index

Corrected Reticulocyte Count

Transferrin Saturation Calculator

Iron Deficit Calculator

HFE Haemochromatosis Risk Estimator

Hepatic Iron Index

DAT Interpretation Algorithm

Coombs-Negative Haemolysis Checklist

PLASMIC Score

Have feedback about this calculator?Let us know.