Leucostasis Risk Threshold

Hyperleukocytosis Emergency: Risk depends on blast size and deformability. AML blasts are large and rigid (high risk > 100), while Lymphoblasts are smaller (high risk > 400).

1. Select Diagnosis

2. Entrance Count

WBC (×10^9/L)

Enter count to assess

Guidelines & Evidence

Verified

Last Review: 2026-07-17

When to Use

Evaluating patients with Hyperleukocytosis (WBC > 100 × 10⁹/L) for signs and symptoms of leucostasis.

Triage of Acute Myeloid Leukemia (AML) vs. Acute Lymphoblastic Leukemia (ALL) based on risk thresholds.

Guiding the necessity for urgent cytoreduction or leukapheresis.

Pathophysiology

Leucostasis occurs when high concentrations of large, non-deformable blasts increase blood viscosity and cause endothelial damage and local hypoxia in the microvasculature.

How it Works

WBC (× 10⁹/L) Risk Levels

Diagnosis	High Risk Threshold	Clinical Context
AML	> 100	High risk; large, sticky blasts cause stasis easily.
ALL	> 400	Lower risk; small lymphoblasts are more deformable.
CML (Chronic)	> 500	Very low risk; mature cells are small and deformable.

The 'Sick' Organ Signs

Pulmonary: Dyspnea, tachypnea, "white out" on CXR (low sensitivity).

Neurological: Confusion, altered mentation, visual changes, papilledema.

Penile: Priapism (more common in CML/AML).

Last Comprehensive Review: 2026-07-17

In Recent Clinical News

Scanning Medical Journals

No new significant updates or guidelines matching this topic were found today. We will check again soon.

Leucostasis Risk Threshold

When to Use

When to Use

Pathophysiology

How it Works

WBC (× 10⁹/L) Risk Levels

The 'Sick' Organ Signs

Clinical Pearls

Pseudo-hypoxemia

Cytoreduction Timing

The Evidence

Primary Consensus

How I treat hyperleukocytosis in acute myeloid leukemia.

Hyperleukocytosis, leukostasis and tumor lysis syndrome: the integrated management of specific medical emergencies in acute leukemia.

Origins & History

Standard Standards

In Recent Clinical News

Leucostasis Risk Threshold

When to Use

When to Use

Pathophysiology

How it Works

WBC (× 10⁹/L) Risk Levels

The 'Sick' Organ Signs

Clinical Pearls

Pseudo-hypoxemia

Cytoreduction Timing

The Evidence

Primary Consensus

How I treat hyperleukocytosis in acute myeloid leukemia.

Hyperleukocytosis, leukostasis and tumor lysis syndrome: the integrated management of specific medical emergencies in acute leukemia.

Origins & History

Standard Standards

In Recent Clinical News