What are the limitations of the thrombocytopaenia differential?

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

How does the thrombocytopaenia differential compare to other Hematology scores?

The thrombocytopaenia differential 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 thrombocytopaenia differential free to use?

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

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Thrombocytopaenia Differential

Diagnostic Algorithm: Systematic triage of low platelets. Always rule out clumping (Pseudothrombocytopenia) and fragmentation (TMA) first.

1. Rule out Artifacts

Does the blood film show platelet clumping, or are there giants platelets in an EDTA sample?

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Systematic diagnostic workup for an unexpected low platelet count.

Differentiating common causes (ITP, Gestational) from rare/emergent causes (TMA, TTP).

Interpreting laboratory markers like MPV and IPF in the context of thrombocytopenia.

The First Step

Always rule out "Pseudothrombocytopenia" (platelet clumping in EDTA) by examining the peripheral blood film or repeating the draw in a Citrate or Heparin tube.

Section 2

Formula & Logic

Diagnostic Branches

Mechanism	Lab Clues	Common Causes
Production Failure	Low IPF, Low Retics, Macro- or Microcytosis	MDS, B12/Folate deficiency, Chemotherapy, Alcohol
Increased Destruction	High IPF, High MPV, Healthy RBCs	ITP, Drug-induced (Heparin/DITP), Gestational
Consumption / TMA	Schistocytes on film, High LDH, Low Haptoglobin	TTP, HUS, DIC, HELLP Syndrome
Sequestration	Splenomegaly on exam/imaging	Portal Hypertension (Cirrhosis), Myelofibrosis

Section 3

Pearls/Pitfalls

IPF Usage

The Immature Platelet Fraction (IPF) is the "Retics for Platelets". A high IPF (> 10%) suggests a marrow that is working hard to replace destroyed platelets, making ITP much more likely than MDS.

The 'Sick' Film

A low platelet count associated with Schistocytes (fragmented RBCs) is a medical emergency until TTP is ruled out. Do NOT wait for a baseline or clinical symptoms—consult hematology immediately.

Section 4

Evidence Appraisal

Primary Strategy

A systematic approach to the diagnosis of thrombocytopenia.

Arnold DM et al. • Mayo Clinic Proceedings. 2017;92(11):1731-1736.

View Source

Section 5

Literature

Consensus

This algorithmic approach reflects the standard teaching across American (ASH) and British (BSH) societies, focusing on the synthesis of clinical history and film morphology.

Last Comprehensive Review: 2026

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Systematic diagnostic workup for an unexpected low platelet count.

Differentiating common causes (ITP, Gestational) from rare/emergent causes (TMA, TTP).

Interpreting laboratory markers like MPV and IPF in the context of thrombocytopenia.

The First Step

Always rule out "Pseudothrombocytopenia" (platelet clumping in EDTA) by examining the peripheral blood film or repeating the draw in a Citrate or Heparin tube.

Section 2

Formula & Logic

Diagnostic Branches

Mechanism	Lab Clues	Common Causes
Production Failure	Low IPF, Low Retics, Macro- or Microcytosis	MDS, B12/Folate deficiency, Chemotherapy, Alcohol
Increased Destruction	High IPF, High MPV, Healthy RBCs	ITP, Drug-induced (Heparin/DITP), Gestational
Consumption / TMA	Schistocytes on film, High LDH, Low Haptoglobin	TTP, HUS, DIC, HELLP Syndrome
Sequestration	Splenomegaly on exam/imaging	Portal Hypertension (Cirrhosis), Myelofibrosis

Section 3

Pearls/Pitfalls

IPF Usage

The Immature Platelet Fraction (IPF) is the "Retics for Platelets". A high IPF (> 10%) suggests a marrow that is working hard to replace destroyed platelets, making ITP much more likely than MDS.

The 'Sick' Film

A low platelet count associated with Schistocytes (fragmented RBCs) is a medical emergency until TTP is ruled out. Do NOT wait for a baseline or clinical symptoms—consult hematology immediately.

Section 4

Evidence Appraisal

Primary Strategy

A systematic approach to the diagnosis of thrombocytopenia.

Arnold DM et al. • Mayo Clinic Proceedings. 2017;92(11):1731-1736.

View Source

Section 5

Literature

Consensus

This algorithmic approach reflects the standard teaching across American (ASH) and British (BSH) societies, focusing on the synthesis of clinical history and film morphology.

Last Comprehensive Review: 2026

Related Hematology Tools

ICANS Grading

aGvHD Grading

NIH Chronic GvHD Scoring

Sickle Cell Disease Risk

Thalassaemia Transfusion Threshold

NTDT Iron Burden Estimator

HbS Percentage Target Calculator

ITP Bleeding Score

IWG ITP Response Criteria

WHO Bleeding Scale

Have feedback about this calculator?Let us know.

Thrombocytopaenia Differential

Diagnostic Algorithm: Systematic triage of low platelets. Always rule out clumping (Pseudothrombocytopenia) and fragmentation (TMA) first.

1. Rule out Artifacts

Does the blood film show platelet clumping, or are there giants platelets in an EDTA sample?

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Systematic diagnostic workup for an unexpected low platelet count.

Differentiating common causes (ITP, Gestational) from rare/emergent causes (TMA, TTP).

Interpreting laboratory markers like MPV and IPF in the context of thrombocytopenia.

The First Step

Always rule out "Pseudothrombocytopenia" (platelet clumping in EDTA) by examining the peripheral blood film or repeating the draw in a Citrate or Heparin tube.

Section 2

Formula & Logic

Diagnostic Branches

Mechanism	Lab Clues	Common Causes
Production Failure	Low IPF, Low Retics, Macro- or Microcytosis	MDS, B12/Folate deficiency, Chemotherapy, Alcohol
Increased Destruction	High IPF, High MPV, Healthy RBCs	ITP, Drug-induced (Heparin/DITP), Gestational
Consumption / TMA	Schistocytes on film, High LDH, Low Haptoglobin	TTP, HUS, DIC, HELLP Syndrome
Sequestration	Splenomegaly on exam/imaging	Portal Hypertension (Cirrhosis), Myelofibrosis

Section 3

Pearls/Pitfalls

IPF Usage

The Immature Platelet Fraction (IPF) is the "Retics for Platelets". A high IPF (> 10%) suggests a marrow that is working hard to replace destroyed platelets, making ITP much more likely than MDS.

The 'Sick' Film

A low platelet count associated with Schistocytes (fragmented RBCs) is a medical emergency until TTP is ruled out. Do NOT wait for a baseline or clinical symptoms—consult hematology immediately.

Section 4

Evidence Appraisal

Primary Strategy

A systematic approach to the diagnosis of thrombocytopenia.

Arnold DM et al. • Mayo Clinic Proceedings. 2017;92(11):1731-1736.

View Source

Section 5

Literature

Consensus

This algorithmic approach reflects the standard teaching across American (ASH) and British (BSH) societies, focusing on the synthesis of clinical history and film morphology.

Last Comprehensive Review: 2026

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Systematic diagnostic workup for an unexpected low platelet count.

Differentiating common causes (ITP, Gestational) from rare/emergent causes (TMA, TTP).

Interpreting laboratory markers like MPV and IPF in the context of thrombocytopenia.

The First Step

Always rule out "Pseudothrombocytopenia" (platelet clumping in EDTA) by examining the peripheral blood film or repeating the draw in a Citrate or Heparin tube.

Section 2

Formula & Logic

Diagnostic Branches

Mechanism	Lab Clues	Common Causes
Production Failure	Low IPF, Low Retics, Macro- or Microcytosis	MDS, B12/Folate deficiency, Chemotherapy, Alcohol
Increased Destruction	High IPF, High MPV, Healthy RBCs	ITP, Drug-induced (Heparin/DITP), Gestational
Consumption / TMA	Schistocytes on film, High LDH, Low Haptoglobin	TTP, HUS, DIC, HELLP Syndrome
Sequestration	Splenomegaly on exam/imaging	Portal Hypertension (Cirrhosis), Myelofibrosis

Section 3

Pearls/Pitfalls

IPF Usage

The Immature Platelet Fraction (IPF) is the "Retics for Platelets". A high IPF (> 10%) suggests a marrow that is working hard to replace destroyed platelets, making ITP much more likely than MDS.

The 'Sick' Film

A low platelet count associated with Schistocytes (fragmented RBCs) is a medical emergency until TTP is ruled out. Do NOT wait for a baseline or clinical symptoms—consult hematology immediately.

Section 4

Evidence Appraisal

Primary Strategy

A systematic approach to the diagnosis of thrombocytopenia.

Arnold DM et al. • Mayo Clinic Proceedings. 2017;92(11):1731-1736.

View Source

Section 5

Literature

Consensus

This algorithmic approach reflects the standard teaching across American (ASH) and British (BSH) societies, focusing on the synthesis of clinical history and film morphology.

Last Comprehensive Review: 2026

Related Hematology Tools

ICANS Grading

aGvHD Grading

NIH Chronic GvHD Scoring

Sickle Cell Disease Risk

Thalassaemia Transfusion Threshold

NTDT Iron Burden Estimator

HbS Percentage Target Calculator

ITP Bleeding Score

IWG ITP Response Criteria

WHO Bleeding Scale

Have feedback about this calculator?Let us know.