Could any constituent of normal human urine produce a false positive in a Kastle-Meyer test for presence of blood?

From my understanding, one forensic test for the presence of traces of blood at a crime scene is (or was) the Kastle-Meyer test. Doing some research, I understand that in the test, hemoglobin reacts with hydrogen peroxide which oxidizes phenolphthalin into phenolphthalein which then changes it's colour to bright pink. 


My question is, are there any constituents of normal urine that could cause a false positive in this test?


To be clear, my interest is academic, not personal.


