Even if the sampling
procedure has been carried out meticulously, urine samples will often
contain normal flora that will grow in the large section of the test.
The content of normal flora in urine samples is variable.
Normal
flora consists primarily of coagulase-negative staphylococci (CNS) .
The normal flora will grow into small white colonies.
Photo 1. Staphylococcus sp.= Normal flora. Small white colonies present in the large section only : No bacterial UTI
Photo 2. Small white colonies present as background of large section
only. A few red colonies are also present (= contaminants): No
bacterial UTI
Photo 3. Small white colonies present as background in the large
section. A few red and blue colonies are also present (=contaminants):
No bacterial UTI
