white spot in underwear

I was just doing my 5 year old boys laundry, and noticed two of his underwear have white spots in the area of the penis. One of them was quite large and the other was smaller, they are not circles, but like smears. This may sound gross, I smelled them to see what it was, but because he is 5 and still having accidents, all I could smell was urine. Does anyone else have any suggestions as to what this might be? I know its not diaper cream.

[RockRose]

White spots in underwear can be a sign of diabetes.

http://www.uihealthcare.com/topics/medicaldepartments/pediatrics/diabetes/index.html

[inquisitivemom789]

Thanks for your reply, we had him tested, no diabetes. Still want to find out what these white spots are though.....