Monday, December 15, 2008


A healthy asymptomatic adolescent enrolls as a test subject for a research experiment. A bunch of baseline tests are taken, all of which are normal except for mild isolated proteinuria (1g/d). So you ask him to do the following test:
-Discard the first morning void.
-Obtain a 16 hour collection between 7am and 11pm with the patient performing normal activities.
-Obtain a separate 8 hour collection between 11pm and 7am.

While the daytime collection has high urine protein, the overnight collection has 30mg/8 hours.

Challenge: What's the diagnosis?


Stephanie said...

the patient wasn't following directions?

Craig Chen said...


This is orthostatic proteinuria, a relatively common finding in adolescents (2-5%) but uncommon in those over 30. It is characterized by increased protein excretion in the upright position but nomal excretion when the patient is supine. The mechanism is unclear. It is benign and does not require further evaluation or therapy.

Source: UpToDate.