Assessment of pancytopenia

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

Severe pancytopenia

In all cases of severe pancytopenia (symptomatic anaemia, absolute reticulocyte count <60 x 10⁹/L [<60,000/microlitre], WBC <0.5 x 10⁹/L [<500/microlitre], and platelets <20 x 10⁹/L [<20 x 10³/microlitre]), investigation is mandatory within 24 to 48 hours. Supportive therapy with red blood cell and platelet transfusion, and broad-spectrum antibiotics to treat anaemia, bleeding, and/or infection, respectively, may need to be initiated before the underlying cause has been ascertained.

Acute myeloid leukaemia

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, dyspnoea, dizziness, bleeding, easy bruising, and recurrent infections. Most patients are treated with chemotherapy induction and consolidation regimens. Haematopoietic stem cell transplantation is also beneficial in select patients.

Acute lymphoblastic leukaemia

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

Acquired aplastic anaemia

This rare condition affecting all age groups is characterised by pancytopenia with reduced or absent haematopoiesis in the bone marrow in the absence of a malignant infiltrate or fibrosis. Severe aplastic anaemia (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 <0.5 x 10⁹/L (<500/microlitre) (very severe aplastic anaemia [VSAA] <0.2 x 10⁹/L [<200/microlitre])

• platelets <20 x 10⁹/L (<20 x 10³/microlitre)

• reticulocyte count <60 x 10⁹/L (<60 x 10³/microlitre) using an automated reticulocyte count.

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