This document discusses urinary tract infections (UTIs). It defines different types of UTIs including cystitis, pyelonephritis, and asymptomatic bacteriuria. Acute UTIs can be simple or complicated, with complicated UTIs showing signs of infection beyond the bladder like fever or flank pain. Diagnosis involves urine testing and symptoms. Most patients don't require imaging. Treatment depends on severity and involves antibiotics. Hospitalization may be needed for high fever, pain, inability to take oral medications, or suspected obstruction.

1. Urinary Tract Infections

2. INTRODUCTION
Urinary tract infections (UTIs) include
- cystitis (infection of the bladder/lower urinary tract) .
- pyelonephritis (infection of the kidney/upper urinary tract).

3. Categorization of UTIs
Acute simple cystitis  Acute UTI that is presumed to be confined to the bladder .
 There are no signs or symptoms that suggest an upper tract or systemic infection .
Acute complicated UTI  Acute UTI accompanied by signs or symptoms that suggest extension of infection
beyond the bladder:
- Fever (>37.7°C)
- Chills, rigors, significant fatigue or malaise beyond baseline, or other features of
systemic illness
- Flank pain
- Costovertebral angle tenderness
- Pelvic or perineal pain in men, which can suggest accompanying prostatitis
Special populations with unique
management considerations
Pregnant women
Renal transplant recipients
By this definition, pyelonephritis is a complicated UTI, regardless of patient characteristics.

4. Typical presentation
• Symptoms and signs of cystitis include dysuria, urinary frequency and
urgency, suprapubic pain, and hematuria.
• Symptoms and signs of pyelonephritis classically include fever, chills,
flank pain, costovertebral angle tenderness, and nausea/vomiting .

5. Diagnosis
The diagnosis of acute complicated UTI is made in the following clinical scenarios:
Symptoms of cystitis (dysuria, urinary urgency, and/or urinary frequency) along with fever
(>37.7ºC) or other signs or symptoms of systemic illness, such as chills, rigors, or acute
mental status changes. In such cases, pyuria and bacteriuria support the diagnosis.
Flank pain and/or costovertebral angle tenderness in the setting of pyuria and bacteriuria.
This is suggestive of pyelonephritis. Fever and typical symptoms of cystitis are usually
present, but their absence does not rule out the diagnosis. CT findings that support the
diagnosis include low attenuation extending to the renal capsule on contrast enhancement
with or without swelling and complications such as renal abscesses. However, a normal CT
does not rule out the possibility of mild pyelonephritis.
Fever or sepsis without localizing symptoms in the setting of pyuria and bacteriuria may be
attributed to UTI if other causes have been ruled out. Careful clinical assessment is
necessary. The diagnosis of acute complicated UTI is unlikely if pyuria is absent.

6. • The presence of bacteriuria (≥105 colony-forming units/mL of a
uropathogen) with or without pyuria in the absence of any symptom
that could be attributable to a UTI is called Asymptomatic Bacteriuria
and generally does not warrant treatment in nonpregnant patients
who are not undergoing urologic surgery.

7. Imaging
Most patients with acute complicated UTI do not warrant imaging studies
for diagnosis or management.
Imaging is generally reserved for those who are severely ill, have
persistent clinical symptoms despite 48 to 72 hours of appropriate
antimicrobial therapy, or have suspected urinary tract obstruction .
 Imaging is also appropriate in patients who have recurrent symptoms
within a few weeks of treatment .
Computed tomography (CT) scanning of the abdomen and pelvis (with
and without contrast) is generally the study of choice to detect anatomic
or physiologic factors associated with acute complicated UTI

8. MANAGEMENT
1. Persistently high fever (>38.4°C ) or pain
2. Marked debility
3. Inability to maintain oral hydration or take oral medications
4. Suspected urinary tract obstruction is suspected
5. Concerns regarding patient adherence.
General Indications for hospitalization

9. Empiric antimicrobial therapy
Outpatient Setting
Suspect multidrug-resistant gram-negative urinary tract infection in patients with a history of any of the following in the prior
three months:
•A multidrug-resistant gram-negative urinary isolate
•Inpatient stay at a health care facility (eg, hospital, nursing home, long-term acute care facility)
•Use of a fluoroquinolone, trimethoprim-sulfamethoxazole, or broad-spectrum beta-lactam (eg, third or later generation
cephalosporin)*
•Travel to parts of the world with high rates of multidrug-resistant organisms
¶
NOTE: The predictive value of these risk factors for multidrug-resistant gram-negative urinary tract infections has not
been systematically evaluated. In particular, the time interval since these exposures is not well validated. The threshold for
empirically covering a multidrug-resistant infection varies with the severity of infection, with a lower threshold warranted for more
severe disease.
Risk factors for multidrug-resistant gram-negative urinary tract infections

11. Empiric antimicrobial therapy
inpatient Setting

12. • Any patients who have worsening symptoms following initiation of
antimicrobials, persistent symptoms after 48 to 72 hours of
appropriate antimicrobial therapy, or recurrent symptoms within a
few weeks of treatment should have additional evaluation, including
abdominal/pelvic imaging (generally with computed tomography if
not already performed) for factors that might be compromising
clinical response.
• Urine culture and susceptibility testing should be repeated, and
treatment should be tailored to the susceptibility profile of other
causative organisms isolated.

13. • For patients who had hematuria on initial presentation, a urinalysis
should be repeated several weeks following antimicrobial therapy to
evaluate for persistent hematuria.