Could Brown Matter During Urination In An Infant Be A Sign Of Infection?

Hi, my 12-month old son has brown matter on his diaper when he urinates. At first, I thought it was dark concentrated urine, as he seems to be suffering from a virus and was vomiting and having diarrhea... However, he is now urinating more frequently and doesn't seem dehydrated. Could the brown matter be a sign of an infection?