Hemochromatosis: A genetic disorder characterized by excessive iron absorption, leading to elevated serum iron levels. The absence of anemia in this case does not rule out hemochromatosis, as iron overload can occur without significant anemia, especially in early stages.

Hemosiderosis: A condition where there is an accumulation of iron in the body, but not to the extent seen in hemochromatosis. This can be due to repeated blood transfusions, excessive iron supplementation, or other causes.
Acute Iron Intoxication: Although less common, acute ingestion of large amounts of iron can lead to high serum iron levels without anemia, at least initially.
Chronic Liver Disease: Certain liver conditions can lead to an increase in serum iron due to the liver's role in iron metabolism and storage.

Thalassemia Major: While typically associated with anemia, early or mild cases might not present with significant anemia but could have elevated serum iron due to transfusion therapy or increased iron absorption.
Porphyria Cutanea Tarda: A disorder of porphyrin metabolism that can lead to increased iron levels. It's crucial to consider this diagnosis due to its potential for significant morbidity if left untreated.

Aceruloplasminemia: A rare genetic disorder characterized by a lack of ceruloplasmin, leading to iron accumulation in the body.
Atransferrinemia: A very rare condition where there is a deficiency of transferrin, the protein responsible for transporting iron in the blood, leading to elevated serum iron levels.
Neonatal Hemochromatosis: A rare condition affecting newborns, characterized by severe iron overload. Though it presents at birth, it's a consideration in the differential for high serum iron without anemia in infants.