# The nurse is conducting a comprehensive assessment of a 70-year-old patient with AML who has a white blood cell count of 150,000/μL. Which assessment finding would be most indicative of leukostasis, a life-threatening complication requiring immediate intervention?

> source: MyMerci (mymerci.kr)  
> url: https://mymerci.kr/pages/nclex_q.php?qn_id=540670  
> language: ko  
> subject: Adult Health

## 문제

The nurse is conducting a comprehensive assessment of a 70-year-old patient with AML who has a white blood cell count of 150,000/μL. Which assessment finding would be most indicative of leukostasis, a life-threatening complication requiring immediate intervention?

## 보기

1. Petechiae and ecchymoses on the lower extremities
2. Oral temperature of 101.8°F (38.8°C) with chills
3. Altered mental status with visual disturbances and dyspnea **✔ 정답**
4. Fatigue and weakness with pale mucous membranes

**정답: 3**

## 해설

Altered mental status with visual disturbances and dyspnea indicates leukostasis affecting CNS and lungs, a life-threatening emergency. Other options represent common AML complications (bleeding, infection, anemia) but are less immediately critical.

## 심화 해설

Understanding the Clinical Scenario

The patient presents with acute myeloid leukemia (AML) and a white blood cell (WBC) count of 150,000/μL. This extreme elevation defines hyperleukocytosis, a hematologic emergency most often defined as a WBC count greater than 100,000/μL in AML [3]. The primary life-threatening complication of hyperleukocytosis is leukostasis, a clinical syndrome caused by the accumulation of leukemic blast cells in the microvasculature, leading to impaired tissue perfusion due to hyperviscosity [1,2]. Recognizing the signs and symptoms of leukostasis is critical because it is associated with severe complications, high early mortality, and requires immediate intervention [2,3].

Analysis of Answer Choices

1. Petechiae and ecchymoses on the lower extremities

While these findings are common in AML due to thrombocytopenia, they are indicative of bleeding risk and impaired hemostasis, not specifically the microvascular occlusion seen in leukostasis. This is a general complication of marrow failure, not the direct result of hyperviscosity from blast cell aggregation.

2. Oral temperature of 101.8°F (38.8°C) with chills

Fever and chills in a patient with AML and a high WBC count are concerning for infection, which is another major risk due to neutropenia despite the high total WBC count (as the cells are non-functional blasts). While a medical emergency, this presentation points toward sepsis or infection, not the direct vascular obstructive pathophysiology of leukostasis.

3. Altered mental status with visual disturbances and dyspnea

This is the correct answer. Leukostasis leads to the occlusion of small blood vessels by leukemic blasts. The clinical manifestations depend on the organ systems involved. Central nervous system (CNS) involvement results in altered mental status and visual disturbances. Pulmonary vascular involvement leads to dyspnea and respiratory distress. The underlying mechanism is vascular engorgement and hyperviscosity, which directly impairs blood flow and oxygen delivery [1]. Pulmonary function tests in such patients have demonstrated supranormal diffusing capacity for carbon monoxide (DLCO), a finding attributed to increased pulmonary capillary blood volume from vascular engorgement, which normalizes with cytoreduction [1]. The triad of CNS changes, visual symptoms, and respiratory distress is a classic and ominous presentation of symptomatic leukostasis requiring immediate intervention, such as leukapheresis or prompt initiation of chemotherapy [3,4].

4. Fatigue and weakness with pale mucous membranes

These findings are classic for anemia, another common consequence of bone marrow failure in AML. Like thrombocytopenia, anemia is a general complication of the disease and its treatment, but it does not represent the acute, life-threatening microvascular crisis of leukostasis.

Deep Dive into Leukostasis Pathophysiology and Intervention

The high mortality associated with hyperleukocytosis is mainly secondary to the effects of leukostasis [4]. The leukemic blasts in AML are larger and less deformable than mature leukocytes, contributing directly to increased blood viscosity. When they aggregate in the microcirculation of the brain and lungs, they cause endothelial damage, local hypoxia, and hemorrhage. This explains the specific constellation of symptoms in the correct answer. Recognizing this clinical picture is the trigger for emergent management. While definitive therapy is the prompt initiation of chemotherapy [4], a procedure called leukapheresis (or therapeutic leukocytapheresis) can be used as an adjunctive strategy to rapidly and safely reduce the WBC count and alleviate symptoms of leukostasis by mechanically removing leukocytes from the peripheral blood [2,4].References (research sources)

- [1]Elevated <i>D</i> <sub>LCO</sub> and pulmonary function evolution during treatment in a patient with hyperleukocytosis and leukostasis.Research articleArce SC, Monti PM, Cortés Guerrieri VB. (2026) · DOI: 10.1183/20734735.0316-2025

- [3]Twenty Years of Therapeutic Leukocytapheresis in Newly Diagnosed Acute Myeloid Leukemia: Insights From A Single Center.Research articleLatal V, Skoumalova I, Palova M, Szotkowski T, Cernan M, Navratilova J, Urbankova H, Pikalova Z, Raida L, Faber E, Papajik T. (2026) · DOI: 10.1002/jca.70111

- [4]Leukapheresis in Pediatric T-ALL with Extreme Hyperleukocytosis: A Case Highlighting the Importance of Early Recognition.Case reportGuild A, Salomon J, Thakker J, Williams SM, Ford J. (2026) · DOI: 10.1177/23247096261429199

## 임상 시나리오

Recognizing Leukostasis in HyperleukocytosisA Life-Threatening Oncologic Emergency
In AML, a WBC count over 100,000/μL defines hyperleukocytosis, which can lead to leukostasis. This occurs when leukemic blast cells aggregate and occlude the microvasculature, causing tissue hypoperfusion and hyperviscosity.

The most critical assessment findings are signs of end-organ damage. Neurological symptoms like altered mental status, headache, and visual disturbances indicate CNS involvement. Respiratory distress, dyspnea, and hypoxia point to pulmonary leukostasis.

CautionDo not confuse symptoms of leukostasis with those of anemia (fatigue, pallor), thrombocytopenia (petechiae, bleeding), or infection (fever, chills). These are common in AML but require different interventions. Immediate treatment for leukostasis includes leukapheresis and induction chemotherapy.

## 핵심 개념

- **Leukostasis** — A life-threatening oncologic emergency where excessive blast cells increase blood viscosity and occlude microvasculature, most commonly affecting the CNS and lungs.
- **Hyperleukocytosis** — A white blood cell count exceeding 100,000/μL, often seen in acute leukemias, which significantly increases the risk for leukostasis.
- **Acute Myeloid Leukemia (AML)** — A hematologic malignancy characterized by the rapid proliferation of abnormal myeloid blast cells in the bone marrow and blood.

## 같은 주제 문제

- [A nurse is assessing a 28-year-old patient with acute lymphoblastic leukemia (ALL) who was…](https://mymerci.kr/pages/nclex_q.php?qn_id=540669)
- [A nurse is caring for a client with acute lymphoblastic leukemia (ALL) who has been receiv…](https://mymerci.kr/pages/nclex_q.php?qn_id=540671)
- [A nurse is assessing a 65-year-old patient newly diagnosed with acute lymphoblastic leukem…](https://mymerci.kr/pages/nclex_q.php?qn_id=540672)
- [A nurse is caring for a 12-year-old child with acute lymphoblastic leukemia (ALL) who has …](https://mymerci.kr/pages/nclex_q.php?qn_id=540673)
- [A nurse is caring for a patient with acute lymphoblastic leukemia (ALL) who has just compl…](https://mymerci.kr/pages/nclex_q.php?qn_id=540674)
- [A nurse is caring for a client with acute myeloid leukemia (AML) who has developed tumor l…](https://mymerci.kr/pages/nclex_q.php?qn_id=540675)
- [The nurse is monitoring a client with acute lymphoblastic leukemia during chemotherapy tre…](https://mymerci.kr/pages/nclex_q.php?qn_id=540676)
- [The nurse must identify the most critical safety measure for a leukemia patient undergoing…](https://mymerci.kr/pages/nclex_q.php?qn_id=540677)

---

More free questions: [기출문제](https://mymerci.kr/)

_학습 참고용입니다. 실제 임상은 최신 지침과 소속 기관 프로토콜을 따르세요._