Anorectal abscess: Difference between revisions

Line 46: Line 46:
''Causative organisms: Mixed infection with fecal flora for [[anaerobes]] and [[Gram Negatives]] ([[Bacteroides fragilis]] and  [[Escherichia coli]])''
''Causative organisms: Mixed infection with fecal flora for [[anaerobes]] and [[Gram Negatives]] ([[Bacteroides fragilis]] and  [[Escherichia coli]])''


'''Only indicated for:'''<ref>BMJ Best Practice Anorectal [[abscess]] http://bestpractice.bmj.com/best-practice/monograph/644/treatment/step-by-step.html</ref><ref>Guidelines.gov - Practice parameters for the management of perianal [[abscess]] and fistula-in-ano.http://www.guideline.gov/content.aspx?id=36077</ref>
'''Use is controversial'''
*Elderly
*Some recommend use only in high risk patients:<ref>BMJ Best Practice Anorectal [[abscess]] http://bestpractice.bmj.com/best-practice/monograph/644/treatment/step-by-step.html</ref><ref>Guidelines.gov - Practice parameters for the management of perianal [[abscess]] and fistula-in-ano.http://www.guideline.gov/content.aspx?id=36077</ref>
*Systemic signs (fever, leukocytosis)
**Elderly
*Valvular heart disease
**Systemic signs (fever, leukocytosis)
*Cellulitis
**Valvular heart disease
*Immunosuppression
**Cellulitis
**Immunosuppression
*Possibly prevent fistula formation<ref>Mocanu V, Dang JT, Ladak F, et al. Antibiotic use in prevention of anal fistulas following incision and drainage of anorectal abscesses: A systematic review and meta-analysis. Am J Surg. 2019;217(5):910-917.</ref>


'''Treatment options:'''
'''Treatment options:'''
*Augmentin
*[[Ciprofloxacin]] 500mg PO BID '''and''' [[Metronidazole]] 500mg PO TID
*[[Ciprofloxacin]] 500mg PO BID '''and''' [[Metronidazole]] 500mg PO TID



Revision as of 01:07, 15 June 2019

Background

  • Usually begin via blocked anal gland (leads to infection/abscess formation)
    • Can progress to involve any of the potential spaces.
Perianal Ischiorectal Intersphincteric, deep postanal, pelvirectal
Epidemiology Most common Second most common Least common
Symptoms Located close to anal verge, posterior midline, superficial tender mass Larger, indurated, well-circumscribed, located laterally on medial aspect of buttocks Rectal pain, skin signs may not be present
Comments High incidence of fistula formation even with drainage Constitutional symptoms often present

Risk Factors

Clinical Features

  • Worsening pain around bowel movement, with decreased pain post rectal evacuation
  • Perirectal abscesses often accompanied by fever, leukocytosis
    • May only be paplpable via digital rectal exam
  • Tender inguinal adenopathy may be only clue to deeper abscesses

Differential Diagnosis

Anorectal Disorders

Skin and Soft Tissue Infection

Look-A-Likes

Evaluation

  • CT with IV contrast can be useful to define deep abscesses (especially with pain out of proportion to exam)
  • May consider ultrasound or MRI as alternatives

Management

  • Isolated perianal abscess is only type of anorectal abscess that should be treated in ED
    • Consider either linear incision with packing, elliptical incision, or cruciate incision without packing
    • Frequent sitz baths
  • All perirectal abscesses (ischiorectal, intersphincteric, supralevator) should be drained in the OR
  • All anorectal abscesses require surgical referral and followup

Antibiotics

Causative organisms: Mixed infection with fecal flora for anaerobes and Gram Negatives (Bacteroides fragilis and Escherichia coli)

Use is controversial

  • Some recommend use only in high risk patients:[1][2]
    • Elderly
    • Systemic signs (fever, leukocytosis)
    • Valvular heart disease
    • Cellulitis
    • Immunosuppression
  • Possibly prevent fistula formation[3]

Treatment options:

Disposition

Discharge

  • Perianal abscess

See Also

External Links

Rob Orman Lecture

References

  1. BMJ Best Practice Anorectal abscess http://bestpractice.bmj.com/best-practice/monograph/644/treatment/step-by-step.html
  2. Guidelines.gov - Practice parameters for the management of perianal abscess and fistula-in-ano.http://www.guideline.gov/content.aspx?id=36077
  3. Mocanu V, Dang JT, Ladak F, et al. Antibiotic use in prevention of anal fistulas following incision and drainage of anorectal abscesses: A systematic review and meta-analysis. Am J Surg. 2019;217(5):910-917.