Skip to Main Content


  • • Fever

    • Flank, abdominal, back, or thigh pain

    • Leukocytosis




  • • Retroperitoneal abscesses are less common than intraperitoneal abscesses

    • Primary abscesses are caused by hematogenous bacterial spread, most commonly S aureus

    • Primary abscesses are more common in underdeveloped countries

    • Secondary abscesses result from spread of infection from adjacent organs, principally from the intestine

    • Most common cause of retroperitoneal abscesses in developed countries is complicated Crohn disease


Symptoms and Signs


  • • Fever

    • Flank, abdominal, back, or thigh pain

    • Anorexia

    • Weight loss

    • Nausea and vomiting

    • Positive iliopsoas sign

    • Hip pain on extension


Laboratory Findings


  • • Leukocytosis

    • Evidence of inflammation: Elevated C-reactive protein and ESR levels

    • Common to have mild hematuria and pyuria when abscess adjacent to ureter or bladder


Imaging Findings


  • CT scan

    • -Most accurately delineates these lesions and can differentiate between retroperitoneal hematomas or tumors

      -Gas bubbles are diagnostic of a retroperitoneal abscess

      -Helpful in diagnosing the underlying etiology in patients with secondary retroperitoneal abscesses

    • Abscesses are confined to specific compartments whereas neoplasms frequently violate fascial barriers


  • • Etiology of retroperitoneal abscess:

    • -Crohn disease

      -Ruptured appendicitis


      -Perforated diverticulitis

      -Posterior penetrating duodenal ulcer

      -Regional enteritis

      -Retroperitoneal trauma




Rule Out


  • • Retroperitoneal hematoma

    • Retroperitoneal tumors

    • Intra-abdominal process with retroperitoneal extension


  • • CBC

    • Basic chemistries

    • Amylase and lipase

    • UA, culture, and sensitivity

    • Blood cultures

    • Most retroperitoneal abscesses are discovered radiographically during the work-up for another diagnostic consideration (ie, appendicitis)

    • Abdominal/pelvic CT scan with IV and PO contrast essential to characterize


When to Admit


  • • All patients should be admitted for definitive therapy and treatment monitoring


When to Refer


  • • Most patients should be managed by general surgeons

    • Subspecialty referral depends on underlying diagnosis (eg, Crohn disease)


  • • Percutaneous drainage may be attempted in well-defined uniloculated abscesses

    • Percutaneous catheter-based drainage has a lower success in retroperitoneal abscesses than with intra-abdominal abscesses




  • • Most patients will require open surgical debridement and drainage, ideally via an extraperitoneal flank approach




  • • Multiloculated abscesses

    • No clinical improvement within 2 days of percutaneous drainage

    • Involvement of psoas muscle or significant amount of necrotic debris present (catheters provide poor drainage for thick liquid or solid debris)

    • Large stellate-shaped abscesses that dissect along fascial planes




  • • Systemic empiric antibiotics that cover aerobic and anaerobic enteric organisms

    • Directed antibiotic therapy based on operative cultures


Treatment Monitoring


  • • Failure of fever or sepsis to subside within 3 days indicates inadequate drainage

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.


About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessSurgery Full Site: One-Year Subscription

Connect to the full suite of AccessSurgery content and resources including more than 160 instructional videos, 16,000+ high-quality images, interactive board review, 20+ textbooks, and more.

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessSurgery

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.