Chronic Liver Disease (Cirrhosis): This condition often leads to portal hypertension, which can cause splenomegaly. The liver disease itself results in hepatomegaly, making cirrhosis a common cause of both findings.

Viral Hepatitis: Certain viral hepatitis infections can cause both hepatomegaly and splenomegaly due to the body's immune response and potential liver inflammation.
Hematological Malignancies (e.g., Lymphoma, Leukemia): These conditions can infiltrate both the liver and spleen, leading to enlargement of both organs.
Portal Vein Thrombosis: This condition can cause splenomegaly due to increased pressure in the portal vein system and can also affect the liver, leading to hepatomegaly.

Wilson's Disease: A genetic disorder that leads to copper accumulation in the liver and brain. It can cause liver dysfunction and potentially hepatomegaly and splenomegaly. Missing this diagnosis could lead to severe neurological and hepatic complications.
Amyloidosis: A condition characterized by the deposition of amyloid proteins in various organs, including the liver and spleen, leading to their enlargement. It can be life-threatening if not recognized and treated appropriately.
Sickle Cell Disease: A genetic disorder that affects hemoglobin production and can lead to splenomegaly due to repeated splenic infarctions and hepatomegaly due to increased red blood cell turnover and potential liver damage.

Gaucher's Disease: A genetic disorder that leads to the accumulation of glucocerebroside in cells, particularly affecting the spleen, liver, and bone marrow, causing hepatosplenomegaly.
Niemann-Pick Disease: A group of genetic disorders that affect lipid metabolism, leading to the accumulation of lipids in cells, which can cause hepatosplenomegaly among other symptoms.
Lysosomal Storage Diseases: A group of rare genetic disorders that result in the accumulation of toxic substances within cells, potentially leading to hepatosplenomegaly.