urinary%20tract%20infection%20-%20complicated
URINARY TRACT INFECTION - COMPLICATED
Urinary tract infection (UTI) is complicated if the UTI is associated with factors that increases colonization and decreases therapy efficacy. Factors may include one or all of the following: Structural or functional abnormalities of the genitourinary tract; presence of an underlying disease that interferes with host defense mechanisms or the patient being immunocompromised; and being infected by a multi-drug resistant bacteria.
Principles of therapy includes effective antimicrobial antimicrobial therapy, optimal management of the underlying abnormalities or other diseases & adequate life-supporting measures.

Definition

  • Urinary tract infection (UTI) associated w/ a condition [eg structural or functional abnormalities of the genitourinary tract (GUT)] or the presence of an underlying disease that interferes w/ host defense mechanisms, which increases the risks of acquiring infection, failing therapy or having recurrent infections
  • Associated w/ altered microbiology that favors more antimicrobial resistant strains that are sometimes less virulent than those found in uncomplicated UTI

Etiology

  • The spectrum of bacteria causing complicated urinary tract infection (UTI) is much larger than that of uncomplicated UTI & more likely to be antibiotic-resistant
    • Escherichia coli, Proteus, Klebsiella, Pseudomonas, Serratia spp & enterococci are the usual strains found in urine culture
  • Catheter-associated UTI
    • Short-term (<1 week): E coli, Pseudomonas aeruginosa
    • Long-term (>1 week): Proteus mirabilis, E coli, P aeruginosa, Providencia stuartii, Morganella morganii, Citrobacter sp, Enterobacter sp, Enterococcus sp, Candida spp
  • Diabetes mellitus (DM) patients: E coli, Klebsiella pneumoniae, P mirabilis, P aeruginosa, Enterobacter sp, Enterococcus sp, Candida spp
  • Renal transplant patients: E coli, P mirabilis, K pneumoniae, P aeruginosa, Gram-positive cocci, Enterobacter sp, Enterococci sp, Serratia sp, Acinetobacter sp, Citrobacter spp, Corynebacterium urealyticum
  • Neutropenic patients: Gram-negative bacilli especially P aeruginosa, Staphylococcus aureus, Candida sp
  • Patients w/ anatomic abnormalities: E coli, K pneumoniae, P aeruginosa, P mirabilis

Signs and Symptoms

  • A complicated urinary tract infection (UTI) does not necessarily present w/ clinical symptoms
  • Dysuria, urgency, frequency, flank pain, costovertebral angle tenderness, suprapubic pain & fever may or may not be present
  • May present w/ signs of sepsis: Hypotension, temperature >40°C, tender subcostal or intractable nausea & vomiting
  • Symptoms may vary from severe obstructive acute pyelonephritis w/ imminent urosepsis up to a catheter-associated post-op UTI
  • Concomitant medical conditions [eg diabetes mellitus (DM), renal failure] are often present

Risk Factors

Factors that suggest a potential complicated urinary tract infection (UTI):
  • >7 days of symptoms prior to presentation
  • Azotemia due to intrinsic renal disease
  • Chemical or radiation injuries of the uroepithelium
  • Comorbidities that predispose to papillary necrosis (eg sickle cell disease, severe DM, analgesic abuse, Pseudomonas sp infection)
  • Elderly
  • Healthcare-associated infection
  • Immunosuppression
  • Incomplete bladder emptying w/ >100 mL of residual urine
  • Male sex
    • Unless it is the 1st episode of symptomatic lower UTI occurring in young (15-40 years old) otherwise healthy, sexually active male w/ no history/clinical evidence of structural or functional urologic abnormality
  • Obstructive uropathy (eg bladder outlet obstruction, calculi, stones, stricture, tumor)
  • Peri- & postoperative UTI
  • Presence of an indwelling urinary catheter or use of intermittent bladder catheterization
  • Recent antimicrobial use
  • Recent urinary tract intervention
  • Renal insufficiency & transplantation
  • Unresolved UTI due to failed response to antibiotic therapy
  • Urinary tract modifications (eg ileal loop or pouch)
  • Vesicoureteral reflux or other functional abnormalities
  • Residence in an institution providing extended care
Digital Edition
Asia's trusted medical magazine for healthcare professionals. Get your MIMS Infectious Diseases - Malaysia digital copy today!
Sign In To Download
Editor's Recommendations
Most Read Articles
Kavitha G. Shekar, 23 Mar 2016
High school girls (15 to 19 years) on long-acting reversible contraception (LARC) are 60 percent less likely to use condoms compared to contraceptive pill users, findings of a US-based study. This places these girls and their partners at a higher risk for sexually transmitted infections (STIs) including human immunodeficiency virus and reflects their ignorance that condoms are mainly used for pregnancy prevention.