II. Pathophysiology
- Parvovirus B19 infection interrupts Red Blood Cell production by affecting erythroid precursors in marrow
- Results in high Red Blood Cell turn-over
III. Symptoms
- Weakness
- Shortness of Breath
- Fever
IV. Signs
- May be fully compensated with normal Heart Rate and Blood Pressure
- Pallor
- Tachycardia
- Hypotension
V. Labs
-
Hemoglobin decreased from baseline
- Severe Anemia (esp. in children)
-
Reticulocyte Count decreased (<1% during aplastic crisis)
- Secondary to decreased Red Blood Cell production despite acute Anemia
- Contrast with Sickle Cell Hemolytic Crisis and Splenic Sequestration where the Reticulocyte Count is increased
VI. Differential Diagnosis
VII. Management
- Admit with isolation droplet precautions (due to Parvovirus B19)
- Avoid exposing pregnant women
- Consult hematology
- Intravenous Immunoglobulin (IVIG)
-
Blood Transfusion may be needed
- Blood should be cross-matched, Leukocyte depleted, and irradiated
- If stable, avoid Fluid Overload by slow infusion over 4 hours
- Plan to raise Hemoglobin by 1 g/dl
VIII. Course
- Aplasia typically resolves over 1-2 weeks
- After infection resolution, Immunity to Parvovirus B19 reduces risk of recurrent aplastic crisis
IX. Complications
-
Vaso-Occlusive Pain Crisis
- May be triggered by Aplastic Crisis
X. References
- Glassberg and Weingart in Majoewsky (2012) EM: Rap 12(8): 5-6
- Lowe and Wang (2018) Crit Dec Emerg Med 32(11): 17-25