Urine (indwelling catheter): 50-100x 10^6 cfu/L Escherichia coli and >100x 10^6 cfu/L Morganella morganii – Shipped 15 February 2016
MAIN EDUCATIONAL POINTS from M154-1
- Generally, two gram negative isolates at high colony in a urinary infection should be fully worked up. Three or more are most often an indication of contamination and may be rejected or prompt a request for recollection if clinical symptoms persist.
- Intrinsic resistance in some species of gram-negative bacilli should not be overlooked. The isolate may test as susceptible but treatment will likely be ineffective.
- Patients in long term care facilities often have vague symptoms of urinary tract infections. In most cases no more than two isolates at high concentrations should be considered as significant.