Bone-related disorders: Conditions such as osteomalacia, Paget's disease, or bone metastases can cause elevated alkaline phosphatase levels due to increased bone turnover, without significantly affecting liver enzymes.

Pregnancy: During pregnancy, alkaline phosphatase levels can rise due to production by the placenta, while liver enzymes may remain within normal limits.
Vitamin D deficiency: This condition can lead to increased alkaline phosphatase levels as a result of secondary hyperparathyroidism and bone remodeling, without directly affecting liver enzymes.
Hypophosphatasia: A rare genetic disorder characterized by low alkaline phosphatase activity in the context of bone disease, but in some cases, alkaline phosphatase can be elevated, and liver enzymes are typically not affected.

Budd-Chiari syndrome: Although liver enzymes might be normal or only slightly elevated, this condition involves hepatic vein thrombosis and can cause elevated alkaline phosphatase levels due to liver congestion and fibrosis. Missing this diagnosis could be fatal.
Primary biliary cirrhosis: An autoimmune disease of the liver that primarily affects the bile ducts, leading to cholestasis and elevated alkaline phosphatase. Early stages might not significantly elevate liver enzymes, making it a critical diagnosis not to miss.

Wilson's disease: A genetic disorder leading to copper accumulation in the body, primarily affecting the liver and brain. It can present with a variety of liver enzyme abnormalities, including occasionally low levels, and elevated alkaline phosphatase.
Fibrogenesis imperfecta ossium: A rare bone disorder characterized by widespread bone sclerosis and elevated alkaline phosphatase, without significant liver enzyme elevation.