Indications for urine culture in a patient with a urinary tract infection:
(1) pyelonephritis
(2) complicated UTI (below)
(3) recurrent UTI (see below)
(4) some cases of asymptomatic bacteriuria (below)
A urine culture is not necessary in a young woman with UTI symptoms, a urinalysis suggestive of cystitis and none of the indications above.
Complicated UTI:
(1) male patient
(2) elderly patient (>= 65 years)
(3) obstruction or foreign body in the urinary tract
(4) post-voiding urine volume > 100 mL
(5) vesicourethral reflux
(6) recent history of invasive urologic intervention
(7) renal transplant recipient
(8) azotemia (rise in BUN and/or creatinine)
(9) surgically created ileal loop
(10) history of UTI with a resistant organism
(11) immunocompromised host
In a young woman with recurrent urinary tract infection associated with sexual activity, 1-2 urine cultures are sufficient unless a complicating condition is present.
Asymptomatic bacteriuria:
(1) during pregnancy
(2) before and after urologic instrumentation
(3) after definitive removal of a chronic indwelling catheter
