Overview
Acquired aplastic anemia (AA) is a rare, heterogeneous disorder characterized by pancytopenia and hypocellular/hypoplastic bone marrow 12. It is an immune-mediated condition, distinct from inherited bone marrow failures 1. The incidence is 2-3 per million population per year in the Western world, with higher rates in East Asia 2.Diagnosis
Diagnosis is confirmed by pancytopenia and hypocellular bone marrow, following careful exclusion of alternate diagnoses, including hypoplastic myelodysplastic syndromes 1.
Molecular cyto-genomics can help differentiate immune-mediated AA from inherited bone marrow failures 1.
Disease severity is assessed using Camitta criteria 1.Management
Supportive care includes blood and platelet transfusions, antimicrobial prophylaxis, and prompt management of opportunistic infections 1.
For newly diagnosed acquired severe/very severe AA in adults, first-line treatment is horse anti-thymocyte globulin (h-ATG) and ciclosporin-based immunosuppressive therapy (IST) with eltrombopag, or allogeneic hematopoietic stem cell transplant (HSCT) from a matched sibling donor 1.
For severe AA in children, HSCT from a matched sibling donor (MSD) is the first-line treatment 2.
If a matched sibling donor is unavailable for children, options include IST, matched unrelated donor HSCT, or haploidentical HSCT 2.
In adults, unrelated donor HSCT should be considered after lack of response to IST, or upfront for young adults with severe infections and a readily available matched unrelated donor 1.Special Populations
Management of inherited bone marrow failures, AA in pregnancy, and AA in the elderly requires special attention 1.
Guidelines specifically address the diagnosis and management of pediatric patients with AA 2.Key Recommendations
Diagnosis of acquired aplastic anemia requires pancytopenia with hypocellular bone marrow and exclusion of alternative diagnoses like hypoplastic myelodysplastic syndromes 1. (Evidence: Expert opinion)
For newly diagnosed acquired severe/very severe AA in adults, standard first-line treatment is horse anti-thymocyte globulin and ciclosporin-based immunosuppressive therapy with eltrombopag or allogeneic hematopoietic stem cell transplant from a matched sibling donor 1. (Evidence: Expert opinion)
For severe aplastic anemia in children, hematopoietic stem cell transplantation from a matched sibling donor is the first-line treatment 2. (Evidence: Expert opinion)
Discussion in multidisciplinary meetings and involvement of expert centers are strongly recommended to improve patient outcomes due to the rarity and complexity of AA management 1. (Evidence: Expert opinion)References
1 Kulasekararaj A, Cavenagh J, Dokal I, Foukaneli T, Gandhi S, Garg M et al.. Guidelines for the diagnosis and management of adult aplastic anaemia: A British Society for Haematology Guideline. British journal of haematology 2024. link
2 Guarina A, Farruggia P, Mariani E, Saracco P, Barone A, Onofrillo D et al.. Diagnosis and management of acquired aplastic anemia in childhood. Guidelines from the Marrow Failure Study Group of the Pediatric Haemato-Oncology Italian Association (AIEOP). Blood cells, molecules & diseases 2024. link