Blackfan syndrome Other phenotypic abnormalities associated with Fanconi anemia include hyperpigmentation or hypopigmentation, microcephaly, strabismus, small stature, mental retardation, and anomalies of the thumbs and radii The diagnosis may be made in the proper clinical context by the presence of increased chromosomal breakage in lymphocytes cultured in the presence of DNA cross-linking agents Acquired aplastic anemia can also present with severe pallor in children The anemia is usually associated with granulocytopenia and thrombocytopenia Acquired aplastic anemia is often idiopathic but has been associated with exposure to certain drugs and chemicals (e.g., chloramphenicol, felbamate, lindane, gold, benzene, and pesticides), radiation, and viral infections (especially hepatitis) The diagnosis is made by an examination of the bone marrow Transient erythroblastopenia of childhood (TEC) is a condition that is often associated with a recent viral illness and is characterized by moderate to severe anemia caused by diminished red cell production The age at presentation can vary from infancy to 10 years, with a median of 18 to 26 months The mean corpuscular volume (MCV) is usually normal at the time of diagnosis The reticulocyte count is decreased, and a Coombs test is negative The anemia of TEC may be associated with a normal or moderately decreased white cell count and a normal platelet count Bone marrow examination shows an initial reduction or absence of erythrocytic precursors followed by erythroid hyperplasia during recovery Transient erythroblastopenia that occurs in the first months of life may be difficult to distinguish from Diamond–Blackfan anemia Spontaneous recovery ultimately confirms the diagnosis of TEC Hypoplastic anemia can be the presenting symptom of childhood malignancies The pallor can be severe, and although all three cell lines of the bone marrow are usually affected, anemia may be the only notable hematologic abnormality The diagnosis can be suspected from the presence of other symptoms or findings, such as lymphadenopathy, bruising, limb pain, gum bleeding, or an abdominal mass Red cell aplasia may develop in patients with underlying hemolytic anemias such as hereditary spherocytosis or sickle cell disease (SCD), often in association with parvovirus B19 infection Decreased red cell production in the face of ongoing hemolysis causes an exacerbation of the anemia The elevated reticulocyte count usually seen in hereditary hemolytic anemias falls to inappropriately low levels, often less than 1% Although platelets and white cells are generally unaffected, they may be mildly decreased Red cell transfusions are appropriate if the anemia is associated with cardiovascular compromise or if continuing reticulocytopenia indicates that the anemia is likely to become severe