OVERVIEW

What is acute hematopoietic arrest?

Acute hematopoietic arrest, also known as aplastic crisis or acute pure red cell aplasia, is a transient cessation of erythropoiesis, leading to a sudden decrease in the number of erythroid precursors in the bone marrow and hemoglobin concentration, as well as a significant reduction in reticulocyte count in peripheral blood. It can be caused by various infections, medications, or systemic autoimmune diseases. Most cases are critical and require aggressive anti-infective or glucocorticoid therapy. Timely treatment generally leads to a cure.

Is acute hematopoietic arrest common in daily life?

Acute hematopoietic arrest is a rare but critical condition.

Which populations are more susceptible to acute hematopoietic arrest?

Acute hematopoietic arrest is more common in patients with underlying diseases such as hereditary spherocytosis, sickle cell anemia, G-6-PD deficiency, autoimmune hemolytic anemia, paroxysmal nocturnal hemoglobinuria, thalassemia, iron deficiency anemia, lymphoma, or leukemia.

SYMPTOMS

What are the manifestations of acute hematopoietic arrest?

Patients with acute hematopoietic arrest often exhibit the following symptoms:

• Severe anemia, characterized by pale complexion, may be accompanied by chills, fever, nausea, vomiting, shortness of breath, abdominal pain, fatigue, etc. In extremely critical cases, confusion, convulsions, shock, heart failure, or acute kidney failure may occur.

• The bone marrow shows characteristic giant proerythroblasts, while peripheral blood reticulocytes decrease or even disappear, bilirubin levels drop, and anemia worsens. Patients with pre-existing red blood cell disorders, such as iron-deficiency anemia, sickle cell anemia, thalassemia, or spherocytosis, may exhibit more pronounced symptoms, which can even be life-threatening.

• If triggered by parvovirus B19 without other concurrent conditions, the condition may resolve on its own. Painful red rashes on the cheeks, limbs, and trunk, as well as joint pain, may occur. Non-specific cold-like symptoms such as fever and vomiting may also appear.

What are the early manifestations of acute hematopoietic arrest?

Extreme paleness of the skin or reduced exercise tolerance may be the earliest signs of the disease. If laboratory tests reveal severe anemia, this condition should be considered.

CAUSES

What are the common causes of acute hematopoietic arrest?

Various infectious factors can induce acute hematopoietic arrest, with parvovirus B19 being the most common, as well as cytomegalovirus, EB virus, Mycoplasma pneumoniae, and mycoplasma. Other underlying diseases include systemic immune diseases such as rheumatoid arthritis and systemic lupus erythematosus, thymoma, drugs, large granular lymphocytic leukemia, etc.

DIAGNOSIS

What tests are needed to diagnose acute hematopoietic arrest?

Tests such as complete blood count, liver and kidney function tests, serum erythropoietin (EPO) levels, EPO antibody testing, viral testing, bone marrow aspiration and biopsy, and abdominal ultrasound of the liver, gallbladder, pancreas, and spleen may be performed.

Why are these tests necessary for acute hematopoietic arrest?

• Complete blood count and liver/kidney function tests: Assess the degree of anemia, blood cell distribution and morphology, and potential liver or kidney damage.

• Serum EPO levels: Evaluate the levels of growth factors essential for the proliferation and differentiation of erythroid progenitor cells.

• EPO antibody testing: Rule out anemia caused by abnormal antibodies.

• Viral testing: Exclude potential viral infections.

• Bone marrow aspiration and biopsy: Examine the proportion and morphology of hematopoietic progenitor cells and assess bone marrow cellularity.

• Abdominal ultrasound (liver, gallbladder, pancreas, spleen): Evaluate organ size, structure, and any abnormal tissue proliferation.

What precautions should be taken for bone marrow aspiration in acute hematopoietic arrest? Is it mandatory?

Before the procedure, coagulation tests should be completed, and allergy history should be reviewed. During the procedure, aseptic techniques must be followed. After the procedure, the patient should rest in bed for 30 minutes, keep the puncture site dry, and avoid bathing for two days. Bone marrow aspiration is crucial for disease diagnosis, severity assessment, and treatment evaluation. Unless contraindicated, this test is generally required.

Which diseases can acute hematopoietic arrest be easily confused with?

• Hemolytic crisis: Typically occurs in individuals with underlying hemolytic disorders. It involves rapid destruction of red blood cells, leading to a sharp drop in hemoglobin, primarily due to intravascular hemolysis. Common triggers include drugs, toxins, certain foods, and bacterial or viral infections. Symptoms include acute anemia, hematuria, chills, fever, nausea, vomiting, abdominal or back pain, and possible acute kidney injury or failure. Severe anemia may cause heart failure or brain damage due to infection. Lab findings show a rapid decrease in hemoglobin, elevated reticulocytes, and sometimes a leukemoid reaction (high white blood cell counts resembling leukemia).
• Megaloblastic crisis (reticulocytopenia crisis): Caused by severe deficiency of erythrocyte precursors or cofactors, leading to uncompensated red blood cell production and sudden severe anemia. Infections or other factors may trigger a hemolytic crisis. Enlarged red blood cells and megaloblastic changes in bone marrow are observed. It commonly occurs in pregnant women, growing infants, and patients recovering from hemolytic or aplastic crises.
• Sequestration crisis: Results from rapid blood pooling in solid organs (e.g., spleen), leading to acute anemia with an unclear mechanism. Symptoms include a sudden drop in hematocrit and hemoglobin, rapid spleen enlargement, abdominal pain, pallor, shortness of breath, tachycardia, lethargy, and thirst. The condition progresses rapidly and can be life-threatening within hours, often occurring in patients with pre-existing hematologic disorders.

What is the fundamental difference between acute hematopoietic arrest and aplastic anemia?

Aplastic anemia is a syndrome caused by various factors leading to bone marrow failure, characterized by reduced hematopoietic cell proliferation in the bone marrow and pancytopenia in peripheral blood.
Acute hematopoietic arrest is a transient cessation of red blood cell production, resulting in a sudden decrease in erythroid precursors in the bone marrow, a drop in hemoglobin, and a significant reduction in reticulocyte count in peripheral blood.

TREATMENT

Does acute hematopoietic arrest require hospitalization?

Acute hematopoietic arrest is a potentially life-threatening critical condition that requires hospitalization.

Does acute hematopoietic arrest affect fertility?

It generally does not affect fertility, but it may impact cardiac function in pregnant women and adversely affect fetal development.

What are the treatment options for acute hematopoietic arrest?

• For severe anemia (hemoglobin below 30 g/L), red blood cell transfusion is required.

• Immunosuppressive therapy, such as glucocorticoids, cyclosporine, or cytotoxic immunosuppressants. Glucocorticoids are the first choice. If ineffective, cyclosporine may be used if reticulocyte count and hemoglobin levels do not improve.

• In cases of infection, early, adequate, and full-course antibiotic therapy should be administered. Antibiotic selection depends on factors like age, weight, genetics, immune status, liver/kidney function, and the causative pathogen.

• For patients with renal insufficiency, malignancies, rheumatic diseases, or sickle cell anemia, colony-stimulating factors may help shorten neutrophil recovery time.

What are the severe consequences if acute hematopoietic arrest is left untreated?

If triggered by parvovirus B19 and without comorbidities, it may resolve spontaneously in about 2 weeks. However, aplastic crisis due to other factors or with underlying diseases can lead to life-threatening multi-organ damage from severe anemia if untreated.

Can acute hematopoietic arrest be cured?

With prompt anemia correction and management of underlying causes, acute hematopoietic arrest can be cured.

Is acute hematopoietic arrest contagious?

Acute hematopoietic arrest itself is not a contagious disease.

When is acute hematopoietic arrest considered cured?

Resolution of symptoms like pallor, fatigue, and dizziness, along with improved red blood cell and hemoglobin levels in blood tests, and restoration of normal erythroid stages in bone marrow examination.

Can acute hematopoietic arrest recur after recovery?

It may recur if triggering factors reappear or after discontinuation of glucocorticoids.

DIET & LIFESTYLE

What should be paid attention to in life care after recovery from acute hematopoietic arrest?

• Keep the home environment clean, disinfect regularly, and prevent infection.
• Consume easily digestible food, provide high-quality protein diet, and pay attention to food hygiene.

PREVENTION

Can Acute Hematopoietic Arrest Be Prevented?

Active treatment of primary diseases and avoiding infections can, to some extent, reduce the occurrence of acute hematopoietic arrest.