Acute cases can threaten hypoxemia through anemia and acute kernicterus through hyperbilirubinemia, particularly in newborns.

In chronic cases anemia and splenomegaly, or enlargement of the spleen due to its increased activity. In some cases the spleen continues to change sizes. Yet in other cases the spleen just continues growing which puts the patient at a greater risk for rupture, which can cause death. Furthermore, the detritus of the broken-down blood cells–bilirubin–accumulates in the gallbladder, and can cause gallstones or “sludge” to develop.