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GU: Urinary Tract Infection
CAPT Leo Kusuda, MC, USNIntroduction: The causative organisms of cystitis, acute prostatitis and pyelonephritis are the same. The
treatment of acute bacterial urinary tract infection (UTI) depends on the location of the infection and the
presence of complicating factors. For the vast majority of infections, the fluoroquinolone antibiotics are highly
effective. Bladder infections (cystitis) are treated for 3 days, kidney (pyelonephritis) for 14 days and prostate
(prostatitis) for 30 days. In the male, it is practical to assume that any leukoesterase positive or culture positive
bacterial urinary tract infection involves the prostate so treat for 30 days. Prostatitis and epididymitis are
covered in separate sections. Urethral discharge suggests urethritis, usually sexually transmitted. Therefore,
primary treatment is different, although the fluoroquinolones are a good alternative. Urethral discharge is
covered in the STD chapter.
Subjective: Symptoms
Burning, frequency, urgency, fever, flank pain.
Objective: Signs
Using Basic Tools: Fever, flank tenderness, fatigue, nausea, vomiting, suprapubic tenderness.
Using Advanced Tools: Urinalysis: Pyuria (leukoesterase +) and nitrite positive indicates infection
(some gram-positive organisms may be nitrite negative). Nitrite + and leukoesterase negative specimen is
contaminated with skin; Gram stain: identify and quantify WBCs, gram-positive or gram-negative rods and
epithelial contamination.
Assessment:
Differential Diagnosis:
Cystitis - burning or frequency, and leukoesterase-positive urine in a female.
Pyelonephritis - fever or flank pain, and leukoesterase-positive urine in a female.
Microhematuria without pyuria - pyelonephritis is less likely; patient may have other reasons for
microhematuria (tumor, stone, etc.).
Peri-ureteral inflammation - inflammation around the ureter (e.g., appendicitis, PID) can result in an abnormal
urinalysis.
Contamination - positive nitrite, negative leukoesterase and negative heme is likely skin contamination of
the urine specimen.
Prostatitis - UTI symptoms in a male with leukoesterase-positive urine.
Plan:
Treatment
Cystitis
Septra DS 1 po bid, nitrofurantoin 100 mg po qid or Macrobid 100 mg po bid, Cipro 250 mg po bid or
Levaquin 250 mg po qd, Keflex 250 mg po qid, or Augmentin 875/125 po bid or 500/125 po tid x 3 days.
Nitrofurantoin is the safest drug in women since it is acceptable to give throughout a pregnancy.
If symptoms do not improve in 2 days, treat patient for 2 weeks. If Augmentin is used, candidal yeast
infections frequently develop. Be prepared to treat with fluconazole 150 mg po single dose or terconazole
vaginal suppositories qd x3 days.
Alternative: 1/3 of woman can clear their cystitis by increased hydration. Doxycycline 100 mg po bid
Cystitis with complicating factors
If patient has history of infections every 1-2 months, place on suppression (see below) until seen by urology.
Women who are postmenopausal, especially greater than 60 years old, frequently take longer to eradicate
cystitis. In such patients, treat for 7-10 days.
Pyelonephritis
Moderately ill: