Which laboratory marker is typically elevated in osteitis fibrosa cystica?

Which laboratory marker is typically elevated in osteitis fibrosa cystica?

• A. Alkaline phosphatase
• B. AST
• C. ALT
• D. Amylase

Answer: (A)

High bone turnover from prolonged excess parathyroid hormone drives osteoblasts to form new bone in an attempt to compensate for the ongoing resorption. Alkaline phosphatase is produced by osteoblasts during this bone formation, so its serum level rises in osteitis fibrosa cystica. This makes alkaline phosphatase a sensitive marker of bone remodeling activity in this condition. The other enzymes listed—AST and ALT from the liver and amylase from the pancreas—aren’t driven by bone turnover, so they aren’t typically elevated due to osteitis fibrosa cystica.

High bone turnover from prolonged excess parathyroid hormone drives osteoblasts to form new bone in an attempt to compensate for the ongoing resorption. Alkaline phosphatase is produced by osteoblasts during this bone formation, so its serum level rises in osteitis fibrosa cystica. This makes alkaline phosphatase a sensitive marker of bone remodeling activity in this condition. The other enzymes listed—AST and ALT from the liver and amylase from the pancreas—aren’t driven by bone turnover, so they aren’t typically elevated due to osteitis fibrosa cystica.