Differential Diagnosis for Isolated Rise in ALP with Bilirubin Normal
Single Most Likely Diagnosis
- Bone disorders (e.g., osteomalacia, Paget's disease, bone metastases): These conditions can cause an isolated increase in alkaline phosphatase (ALP) due to bone isoenzyme elevation without affecting bilirubin levels.
Other Likely Diagnoses
- Hepatic causes (e.g., primary biliary cirrhosis, primary sclerosing cholangitis): Although bilirubin is normal, these conditions can cause an isolated rise in ALP due to cholestasis.
- Vitamin D deficiency: This can lead to increased bone turnover and elevated ALP levels.
- Pregnancy: ALP levels can rise during pregnancy due to the production of placental ALP.
Do Not Miss Diagnoses
- Budd-Chiari syndrome: A rare condition characterized by hepatic vein thrombosis, which can cause an isolated rise in ALP. Missing this diagnosis can be fatal.
- Infiltrative liver diseases (e.g., sarcoidosis, lymphoma): These conditions can cause an isolated rise in ALP and have significant implications if left untreated.
Rare Diagnoses
- Familial pseudohyperphosphatasia: A rare genetic disorder characterized by elevated ALP levels without any apparent bone or liver disease.
- Hypophosphatasia: A rare genetic disorder that affects bone mineralization and can cause elevated ALP levels.
- Wilson's disease: A rare genetic disorder that affects copper metabolism and can cause liver disease, including an isolated rise in ALP.