Evaluation of pancytopenia

Unless the underlying cause is already apparent (and being appropriately managed), the presence of pancytopenia always warrants investigation by a hematologist.

Severe pancytopenia

In all cases of severe pancytopenia (symptomatic anemia [absolute reticulocyte count <60,000/microliter, WBC <500/microliter, and platelets <20 x 10³/microliter]), investigation is mandatory within 24 to 48 hours. Supportive therapy with red blood cell and platelet transfusion, and broad-spectrum antibiotics to treat anemia, bleeding, and/or infection, respectively, may need to be initiated before the underlying cause has been ascertained.

Acute myeloid leukemia

Occurs in all age groups but predominantly in older adults. Cytogenetic abnormalities are prognostically important and affect patient management.[26]Döhner H, Wei AH, Appelbaum FR, et al. Diagnosis and management of AML in adults: 2022 recommendations from an international expert panel on behalf of the ELN. Blood. 2022 Sep 22;140(12):1345-77. https://ashpublications.org/blood/article/140/12/1345/485817/Diagnosis-and-management-of-AML-in-adults-2022 http://www.ncbi.nlm.nih.gov/pubmed/35797463?tool=bestpractice.com ​ Clinical history plus most signs and symptoms usually reflect bone marrow failure. These include fatigue, dyspnea, dizziness, bleeding, easy bruising, and recurrent infections. Most patients are treated with chemotherapy induction and consolidation regimens. Hematopoietic stem cell transplantation is also beneficial in select patients.

Acute lymphoblastic leukemia

This is the most common acute leukemia in childhood, but also occurs in adults. Clinical history plus most signs and symptoms usually reflect bone marrow failure. These include fatigue, dyspnea, dizziness, bleeding, easy bruising, and recurrent infections. Physical exam may reveal pallor and ecchymoses, and lymphadenopathy. Neurologic symptoms and/or signs may occur if central nervous system involvement is present. Treatment uses multiagent dose-intense chemotherapy regimens in induction, consolidation, and maintenance phases.

Acquired aplastic anemia

This rare condition affecting all age groups is characterized by pancytopenia with reduced or absent hematopoiesis in the bone marrow in the absence of a malignant infiltrate or fibrosis. Severe aplastic anemia (SAA) is defined, using the modified Camitta criteria, as having a marrow cellularity <25% with at least 2 of the 3 following criteria:[27]Kulasekararaj A, Cavenagh J, Dokal I, et al. Guidelines for the diagnosis and management of adult aplastic anaemia: a British Society for Haematology guideline. Br J Haematol. 2024 Mar;204(3):784-804. https://www.doi.org/10.1111/bjh.19236 http://www.ncbi.nlm.nih.gov/pubmed/38247114?tool=bestpractice.com [28]DeZern AE, Churpek JE. Approach to the diagnosis of aplastic anemia. Blood Adv. 2021 Jun 22;5(12):2660-71. https://www.doi.org/10.1182/bloodadvances.2021004345 http://www.ncbi.nlm.nih.gov/pubmed/34156438?tool=bestpractice.com

• neutrophils <500/microliter (very severe aplastic anemia [VSAA] <200/microliter)

• platelets <20 x 10³/microliter

• reticulocyte count <60 x 10³/microliter using an automated reticulocyte count.

Clinical history plus most signs and symptoms usually reflect bone marrow failure. These include fatigue, dyspnea, dizziness, bleeding, easy bruising, and recurrent infections.