Diagnostic workflow of CDAs. Flow diagram for the differential diagnosis of CDAs and their related hereditary anemias. This illustrates the main differences between patients with transfusion-dependent (TD) anemia compared with patients with nontransfusion-dependent (NTD) anemia. Light blue shading indicates the main steps to reach diagnosis of CDAs by complete blood count (CBC) analysis and specific tests, such as examination of bone marrow, analysis of band 3 hypoglycosylation by sodium dodecyl sulfate polyacrylamide gel electrophoresis (for CDAII), examination of skeletal malformations (for CDAI), assessment of additional clinical features for syndromic conditions, and evaluation of fetal hemoglobin levels for transcription factor-related CDAs. Light red shading indicates the main steps to reach molecular diagnosis of these conditions. HbF, fetal hemoglobin; MCV, mean corpuscular volume; PLT, platelet count; Ret count, reticulocyte count; RBC, red blood cell; t-NGS, targeted next-generation sequencing; VUS, variant of uncertain significance; WES, whole-exome sequencing; XLTDA, X-linked thrombocytopenia with or without dyserythropoietic anemia.