Urinary Tract Infections

How to Read a Urinalysis

* Signs of Inflammation* Leukocyte Esterace* WBCs

Multiple conditions cause inflammation on a urinalysis. Anything that causes nearby inflammation (appendicitis, pelvic infections, diverticulitis) or slows urine output (dehydration, renal disease) can commonly elevate these markers.

* Signs of bacterial presence (not present in ~25% of proven urinary tract infections!!!)* Nitrites* Bacteria

Asymptomatic Bacteriuria

Generally should NOT be treated with antibiotics. If you were to randomly sample the population you would find bacteria present in approximately…

* 5% of young people* 20% of old people* 50% of patients in long term care

When to Diagnose UTI

* Dysuria AND urinary frequency WITHOUT vaginal symptoms (+LR 20)* Patient self reports that they think their UTI is back (+LR 4)* Urinalysis shows BOTH signs of inflammation and bacterial presence* Combine pretest suspicion with urinalysis findings using clinical judgement

Indwelling Foley Catheters

All patients with an indwelling foley will have a grossly abnormal urinalysis and appearance of urine at baseline. The urinalysis is useless and diagnosis can only be made by clinical judgement

Geriatric Patients

Geriatric patients have minimal symptoms regardless of diagnosis. They can have UTI’s with minimal symptoms. However they can also have appendicitis or kidney stones with minimal symptoms (and asymptomatic bacteriuria at baseline). BE CAREFUL.

Additional Reading

* The best UTI resource I have seen (First10EM)