Tuesday 27 March 2012

Proteinurea: Normal/Abnormal

A 70 kg male performs a 24hour urine collection. The lab report reveals: volume 2.5 L, creatinine 34mmol, protein 240 mg. Do you think this patient has abnormal proteinexcretion? Why?

Answer

To determine adequacy of a 24hour urine collection, one must look at the total amount of creatinineexcreted in the collection period.

Males should excrete 200umol/kg of creatinine per 24 hours and females should excrete 150umol/kg/24 hours.

This patient should haveproduced 70 kg x 200 umol/kg = 14 mmol of creatinine in the 24 hourcollection. Since his collection had 34 mmol ofcreatinine, this represents an overcollection.Therefore, the protein measured is an overestimate of his true 24hour protein excretion. One could estimate that his trueprotein excretion rate would be closer to (14/34) X 240 mg = 99 mg per day,which would fall within the normal range.

No comments:

Post a Comment