Urinary tract infections
(UTI guideline)
Anatomic
Lower: urethritis, cystitis (superficial infection of bladder), prostatitis
Upper: pyelonephritis (inflammatory process of the renal parenchyma), renal abscess
Clinical
Uncomplicated: cystitis in nonpregnant women without underlying structural or
neurological disease
Complicated: upper tract infection or any UTI in men or pregnant women or UTI with
underlying structural or neurological disease (obstruction, reflux, azotemia, transplant,
catheter-related)
Microbiology
Uncomplicated UTI: E.coli(80%), Proteus, Klebsiella, enterococci
Complicated UTI: E,coli(30%), enterococci(20%), Pseudomonas(20%) ,
S.epidermidis(15%), other GNR
Catheter-associated UTI: yeast(30%) , E.coli(25%), other GNR, enterococci,
S.epidermidis
Urethritis: Chlamydia trachomatis, Neisseria gonorrhoeae
Clinical Manifestations
Cystitis: dysuria, urgency, ↑frequency, △ in urine color/odor, suprapubic pain; fever
generally absent
Urethritis: may be identical to cystitis except for urethral discharge
Pyelonephritis: fever, shaking chills, flank or back pain, nausea, vomiting, diarrhea
Renal abscess( intrarenal or perinephric): identical to pyelonephritis except persistent
fever despite appropriate antibiotics
Diagnostic studies
Urinalysis: pyuria+ bacteriuria +/-hematuria
Significant bacterial counts: > 105 CFU/ ml in asymptomatic women, > 103 CFU/ml in
men, > 102 CFU/ml in symptomatic or catheterized patients
Sterile pyuria urethritis, renal tuberculosis, foreign body
Urine gram stain and culture ( from clean-catch midstream or straight-catheterized
specimen)
in pregnant women and in patients undergoing urologic surgery-screen for symptomatic
bacteriuria
blood cultures: consider in complicated UTIs
First-void and midstream urine specimens
Abdominal CT to rule-out abscess in patients with pyelonephritis who fail to defervesce
after 72h
Urologic workup (KUB, renal U/S, abdominal CT, voiding cystography)
Treatment of UTIs
Clinical scenario
Cystitis
Urethritis
Pyelonephritis
Renal abcess
Clinical scenario
TMP-SMX or FQ x 3d or x 10-14
d(complicated)
Asymptomatic bacteriuria in pregnant
women or
Treat for both Neisseria and Chlamydia
Neisseria: ceftriaxone 125 mg IM x1 or
ofloxacin 400 mg POx1
Outpatient: FQ or amoxicillin/clavulanate
or 1st gen.ceph.PO
x 14d
Inpatient: [ampicillin IV+gentamicin] or
ampicillin/sulbactam or FQ or P Ceph 3
or AP Pen X 14 d(△IVPO when patient
improved
Drainage + antibiotics as for
pyelonephritis
Reference:
1.Harrison’s Principles of Internal Medicine,15ed, P1620-1626
2.The Washington Manual of Medical Therapeutics 30 ed, P310-312
3.The Massachusetts General Hospital Handbook of Internal Medicine P6-3
4.The Stanford Guide To Antimicrobial Therapy,2004,P23