Editing Urinary Tract Infections (section)

=== Uncomplicated Acute Bacterial Cystitis ===

==== Definition ====

* '''<span style="color:#ff0000">Diagnosis of acute bacterial cystitis requires (2):'''
*# '''<span style="color:#ff0000">Laboratory confirmation of significant bacteriuria AND'''
*# '''<span style="color:#ff0000">Acute-onset symptoms (lower urinary tract symptoms)'''

==== Pathophysiology ====
* '''Pathogens'''
** '''<span style="color:#ff0000">E. coli is the causative organism in 75-90% of cases of acute cystitis in young women.'''
** '''<span style="color:#ff0000">S. saprophyticus, a commensal organism of the skin, is the second most common cause of acute cystitis in young women, accounting for 10-20% of these infections. Other organisms less commonly involved include Klebsiella and Proteus species and Enterococcus.'''
** '''<span style="color:#ff0000">In men, E. coli and other Enterobacteriaceae are the most commonly identified organisms.'''
* '''Sexual transmission of uropathogens has been suggested''' by demonstrating identical E. coli in the bowel and urinary flora of sex partners

==== Diagnosis and Evaluation ====

* '''<span style="color:#ff0000">Differential Diagnosis (11):</span>'''
#'''<span style="color:#ff0000">Interstitial cystitis/bladder pain syndrome</span>'''
#'''<span style="color:#ff0000">Overactive Bladder</span>'''
#'''<span style="color:#ff0000">Urinary calculi</span>'''
#'''<span style="color:#ff0000">Infectious bacterial or fungal vaginitis</span>'''
#'''<span style="color:#ff0000">Urethral infections caused by sexually transmitted pathogens</span>'''
#'''<span style="color:#ff0000">Vulvar dermatitis</span>'''
#'''<span style="color:#ff0000">Non-infectious vulvovestibulitis</span>'''
#'''<span style="color:#ff0000">Vulvodynia</span>'''
#'''<span style="color:#ff0000">Hypertonic pelvic floor muscle dysfunction</span>'''
#'''<span style="color:#ff0000">Genitourinary syndrome of menopause</span>'''
# '''<span style="color:#ff0000">CIS of the bladder</span>''' (less commonly)
===== History and Physical Exam =====
* '''<span style="color:#ff0000">History'''
** '''<span style="color:#ff0000">Signs and Symptoms'''
***Variable presenting symptoms of cystitis 
***'''<span style="color:#ff0000">Usually include dysuria, frequency, and/or urgency'''
***'''<span style="color:#ff0000">Suprapubic pain, incontinence, hematuria, or foul-smelling urine may develop'''
*** '''In older adults, the symptoms of UTI may be less clear'''
**** Given the subjective nature of these symptoms, '''careful evaluation of their chronicity becomes an important consideration.'''
***** Older females frequently have nonspecific symptoms that may be perceived as a UTI, such as dysuria, cloudy urine, vaginal dryness, vaginal/perineal burning, bladder or pelvic discomfort, urinary frequency and urgency, or urinary incontinence, but these tend to be more chronic
***** '''Acute-onset dysuria, particularly when associated with new or worsening storage symptoms, remains a reliable diagnostic criterion in older females''' living both in the community and in long-term care facilities.
*** '''By definition, acute cystitis is a superficial infection of the bladder mucosa, so <span style="color:#ff0000">fever, chills, and other signs of dissemination are not present.'''
* '''<span style="color:#ff0000">Physical Exam'''
** '''Most have no diagnostic physical findings'''
**'''<span style="color:#ff0000">Abdomen'''
***Some patients may experience suprapubic tenderness
** '''<span style="color:#ff0000">Pelvis'''
***'''<span style="color:#ff0000">Prolapse, urethral tenderness, urethral diverticulum'''
***'''<span style="color:#ff0000">Skene’s gland cyst, or other enlarged or infected vulvar or vaginal cysts'''
***'''<span style="color:#ff0000">Any other infectious and inflammatory conditions (vaginitis, vulvar dermatitis, herpes, and vaginal atrophy</span>''' (genitourinary syndrome of menopause)
***'''Pelvic floor musculature''' for tone, tenderness, and trigger points

===== Laboratory =====
* '''<span style="color:#ff0000">Urinalysis'''
** '''<span style="color:#ff0000">The presumptive laboratory diagnosis of acute cystitis is based on microscopic urinalysis, which indicates microscopic pyuria, bacteriuria, and occasionally hematuria.'''
* '''<span style="color:#ff0000">Urine culture'''
** '''<span style="color:#ff0000">Remains the definitive test'''
***'''Clinical judgment is needed to determine when a culture result represents clinically significant bacteriuria considering the patient presentation, urine collection method, and the presence of other suggestive factors such as pyuria.'''
****'''<span style="color:#ff0000">The definition for clinically significant bacteriuria of >10<sup>5</sup> colony forming units (CFU)/mL represents an arbitrary cut-off.</span>'''
****'''Although > 10<sup>5</sup> CFU/mL for bacterial growth on midstream voided urine may help distinguish bladder bacteriuria from contamination in asymptomatic, pre-menopausal women, <span style="color:#ff0000">a lower 10<sup>2</sup> CFU/mL threshold may be appropriate in symptomatic individuals</span>'''
**'''Obtain repeat urine studies when an initial urine specimen is suspect for contamination, with consideration for obtaining a catheterized specimen'''
***'''Urine culture contamination should be suspected when (3):'''
***#'''Mixed cultures containing ≥2 organisms'''
***#'''Low quantities (<103 CFU/mL) of a pathogenic organism in an asymptomatic patient'''
***#'''Specimen exhibits growth of normal vaginal flora (e.g. Lactobacilli, Group B Streptococci, Corynebacteria, or non-saprophyticus coagulase-negative Staphylococci)'''
***#*'''Growth of these organisms are thought to be contaminant and generally do not require treatment'''
***'''Concomitant urinalysis can also be useful (presence of epithelial cells or mucus on microscopic urinalysis may also suggest contaminant).'''
***'''When there is high suspicion for contamination, consider obtaining a catheterized specimen for further evaluation prior to treatment.'''
***'''Urine specimens should not sit at room temperature for > 30 minutes to facilitate lab diagnosis of UTI.'''

==== Management ====
* '''<span style="color:#ff0000">Antibiotic regimen'''
**'''<span style="color:#ff0000">Preferred (3)'''
**# '''<span style="color:#ff0000">Fosfomycin 3 gram PO x single dose'''
**# '''<span style="color:#ff0000">Nitrofurantoin 100 mg PO BID x 5 days'''
**# '''<span style="color:#ff0000">Trimethoprim-sulfamethoxazole DS 1 pill PO BID x 3 days'''
**'''<span style="color:#ff0000">Alternative when bacteria are resistant to the preferred antibiotics: ciprofloxacin, 250 mg BID x 3 days'''
***'''<span style="color:#ff0000">Fluoroquinolone antibiotics should not be the first line treatment of uncomplicated cystitis.'''
*'''≈90% of women are asymptomatic within 72 hours after initiating antibiotics'''
* '''A follow-up visit or culture is not required in young women who are asymptomatic after therapy.'''
** A follow-up visit, urinalysis, and urine culture are recommended in older women or those with potential risk factors and in men.
** '''Urologic evaluation is unnecessary in women and is usually unnecessary in young men who respond to therapy.  However, UTIs in most men should be considered complicated until proven otherwise.'''
* '''If a patient does not respond to therapy, appropriate microbiologic and urologic evaluations should be undertaken for the causes of unresolved and complicated UTIs.'''