Psoas muscle abscess

Psoas muscle abscess and fluid collections are located in the retrofascial space rather than in the retroperitoneal space because the psoas muscles are located in the iliopsoas compartment posterior to the transversalis fascia, which is the posterior boundary of the retroperitoneum.

Clinical presentation

Psoas muscle abscess may present with fever, flank pain, abdominal pain or limp. Other symptoms are nausea, malaise and weight loss.

Pathology

Psoas muscle abscess may be classified as primary or secondary depending on the presence or absence of underlying disease.

Primary

Primary psoas muscle abscess occurs probably as a result of haematogenous spread of an infectious process from an occult source in the body. Primary psoas muscle abscess can occur in patients with:

Secondary

Spread of infection from gastrointestinal disease (e.g. appendicitis, diverticulitis, Crohn's disease or perforated colon carcinoma) is the most common source of a
secondary psoas muscle fluid collection. 

Renal disease is the second most common source.

They may also occur as a result of a neighbouring spondylodiscitis.

Radiographic features

CT/MRI

Cross-sectional imaging is the method of choice for abscess detection. 

Ultrasonography

It is diagnostic in only 60% of cases of psoas abscess, compared with 80% to 100% for CT. 

Treatment and prognosis

Appropriate antibiotics along with drainage of the abscess is the treatment of choice. This is often treated with a image guided percutaneous drainage, typically CT, due to the retroperitoneal location.

Differential diagnosis

Edit Article Share Article

Article Information

rID: 21395
System: Musculoskeletal
Section: Pathology
Synonyms or Alternate Spellings:
  • Psoas abscess
  • Psoas abscesses
  • Psoas muscle abscesses
  • Iliopsoas abscess
  • Drag
    Case 1
    Drag here to reorder.
  • Drag
    Psoas abscess and...
    Case 2: psoas abscess and left sided renal cyst
    Drag here to reorder.
  • Drag
    Case 3: SIJ and psoas abscess
    Drag here to reorder.
  • Drag
    Case 4: due to splenic tuberculomas
    Drag here to reorder.
  • Drag
    Case 5: on ultrasound
    Drag here to reorder.
  • Drag
    Case 6: due to tuberculous spondylo-discitis
    Drag here to reorder.
  • Drag
    Case 7
    Drag here to reorder.
  • Drag
    Case 8: postoperative psoas collection
    Drag here to reorder.
  • Drag
    Case 9: complicating renal abscess
    Drag here to reorder.
  • Drag
    Case 10
    Drag here to reorder.
  • Drag
    Case 11
    Drag here to reorder.
  • Drag
    Case 12
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert_accept

    Error Unable to process the form. Check for errors and try again.

    Alert_accept Thank you for updating your details.