What laboratory finding is associated with G6PD deficiency?

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a genetic disorder that affects red blood cells, leading to hemolytic anemia under certain stressors like infections, certain foods (e.g., fava beans), and certain medications. One of the hallmark laboratory findings associated with G6PD deficiency during episodes of hemolysis is the presence of bite cells observed on a blood smear.

Bite cells are formed when red blood cells undergo oxidative damage—specifically, when hemoglobin is denatured and precipitates in response to oxidative stress. The macrophages in the spleen recognize these denatured portions and “bite” them out, leading to the characteristic appearance of these cells.

This distinct morphology is a key indicator of G6PD deficiency, particularly during acute hemolytic episodes. The other options mentioned relate to different conditions: target cells are typically seen in conditions like thalassemia or liver disease; ringed sideroblasts are indicative of pyridoxine deficiency or lead poisoning; schistocytes are associated with microangiopathic hemolytic anemia, such as in thrombotic thrombocytopenic purpura (TTP) or hemolytic uremic syndrome (H