Review Question - QID 210023

This patient is presenting with laboratory values suggestive of Paget disease of the bone which is associated with blastic and lytic skeletal lesions.

Paget disease of the bone typically presents in elderly patients with an elevated calcium, elevated alkaline phosphatase, and a pathologic fracture. However, another very common presentation for Paget disease of the bone is an asymptomatic patient with an elevated alkaline phosphatase. To ensure that the alkaline phosphatase is coming from bone (since it can come from the GI tract and the skeleton) a gamma-glutamyltransferase (GGT) level can be used to differentiate the origin (as it will be elevated in liver or gallbladder pathology and normal in a skeletal pathology). Paget disease of the bone is associated with lytic and blastic lesions in the bone.

Incorrect Answers:
Answer 2: Monoclonal plasma cell replication describes multiple myeloma which would likely present with a very elevated calcium and pathological fractures or bone pain.

Answer 3: Reemergence of a hepatitis infection is a possible cause of an elevated alkaline phosphatase level; however, one would expect other symptoms as well as an elevated GGT.

Answer 4: Repeat gastrointestinal tract obstruction is unlikely as her gallbladder has been removed (though a retained stone could still cause these symptoms). Since she is asymptomatic this is possible but less likely.

Answer 5: Qualitative bone defect describes osteomalacia which is possible in this patient; however, the extent to which her alkaline phosphatase is elevated is beyond what one would expect in osteomalacia. In addition, there is no reason to suspect osteomalacia in this patient other than her gender and age, which are risk factors.

Bullet Summary:
Paget disease of the bone can present in an asymptomatic patient with only an elevated alkaline phosphatase and a normal GGT level.