[Hereditary hemolytic anemia in newborns: clinical significance of genetic diagnosis].

Hereditary hemolytic anemia (HHA) is a group of monogenic diseases arising from the increased destruction of circulating erythrocytes. HHA is caused by germline mutations in genes encoding components of the red blood cell membrane, hemoglobin, and enzymes. Comprehensive gene analyses have identified various HHA-associated germline defects. However, early HHA diagnosis can be difficult in newborns because they present with hydrops and severe jaundice, which require urgent blood transfusions. Considering neonatal physiological hemolysis and pediatric infection, we select efficient diagnostic procedures following the exclusion of "syndromic hemolytic diseases". Clinical sequencing is performed for atypical cases, although phenotypic and laboratory tests remain essential for the verification of pathogenicity when certain variants are identified. The diagnostic gene panel can also be useful for predicting prognosis and determining treatment options. Although transfusion-dependent adult patients with HHA are rare in Japan, their management remains challenging. Clinical trials of new drugs and genetic controls are ongoing in other countries. However, the long-term management of a small group of patients with severe HHA must still be addressed in Japan. Here, we review the strategy and clinical significance of using genetic diagnostic methods for HHA in newborns.