RT Book, Section A1 Calado, Rodrigo A2 Murray, Michael F. A2 Babyatsky, Mark W. A2 Giovanni, Monica A. A2 Alkuraya, Fowzan S. A2 Stewart, Douglas R. SR Print(0) ID 1102699872 T1 Aplastic Anemia, Bone Marrow Failure Syndromes T2 Clinical Genomics: Practical Applications in Adult Patient Care YR 2014 FD 2014 PB McGraw-Hill Education PP New York, NY SN 9780071622448 LK accessmedicine.mhmedical.com/content.aspx?aid=1102699872 RD 2024/03/28 AB Disease summary:Aplastic anemia (AA) is the prototypic disease of hematopoietic stem cell failure. It is characterized by an empty bone marrow resulting in low peripheral blood cell counts (pancytopenia).AA can be acquired or inherited. Most common types of inherited AA are Fanconi anemia, dyskeratosiscongenita, and Shwachman-Diamond syndrome.Acquired AA is an immune-mediated condition in which activated type-1 cytotoxic T cells target hematopoietic stem and progenitor cells in the marrow.Whereas congenital AA is more frequent in the first and second decades of life and is associated with physical abnormalities (café-au-lait spots, hyperpigmentation, short stature, abnormal thumbs in Fanconi anemia; nail dystrophy, leukoplakia, and reticular hyperpigmentation in dyskeratosiscongenita; and exocrine pancreatic insufficiency in Shwachman-Diamond syndrome), the incidence of acquired AA is bimodal, peaking in adolescence (15 years) and greater than 50 years and physical anomalies are absent.Differential diagnosis:Other causes of pancytopenia must be excluded: acute leukemia, myelodysplastic syndrome, pernicious anemia, bone marrow infiltration by other neoplasias.It is not uncommon that a constitutional type of aplastic anemia to manifest without the usual clinical findings. Thus, it is necessary to perform ancillary diagnostic tests for the differential diagnosis of inherited bone marrow failure syndromes (Table 33-1), especially in children. Chromosome breakage test is routinely performed for the diagnosis of Fanconi anemia and telomere length measurement for the diagnosis of dyskeratosis congenita.