Pyruvate kinase deficiency is a rare genetic disorder that affects the enzyme responsible for producing ATP, the energy source for cells. It can lead to anemia, jaundice, fatigue, and enlarged spleen. There are various synonyms for pyruvate kinase deficiency such as hemolytic anemia due to pyruvate kinase deficiency, chronic hemolytic anemia, hereditary nonspherocytic hemolytic anemia, and erythrocyte pyruvate kinase deficiency. These synonyms reflect the different ways the disorder is diagnosed and identified depending on the specific symptoms and genetic mutations present in each case. While pyruvate kinase deficiency has no cure, supportive treatments like blood transfusions and splenectomy can improve quality of life for those affected.