Intra-Abdominal Abscess

• • Fever and chills

  • Tachycardia

  • Leukocytosis

  • Focal abdominal tenderness

  • Predisposing condition

Epidemiology

• • Most common causes are

  • -GI perforations

    -Postoperative complications

    -Penetrating trauma

    -Genitourinary infections

  • Abscess forms as sequelae of generalized peritonitis in 33% of cases

  • Intra-abdominal abscess forms adjacent to diseased viscus (eg, perforated appendicitis) or as a result of external contamination (subphrenic abscess)

  • Broadly classified based on anatomic location:

  • -Subdiaphramatic

    -Subhepatic

    -Pericolic

    -Pelvic

    -Interloop abscesses

Symptoms and Signs

• • Fever and chills

  • Tachycardia

  • Focal abdominal tenderness

  • Prolonged ileus or sluggish postoperative recovery

  • Mass seldom appreciated

  • Irritation of contiguous structures manifesting symptoms such as:

  • -Lower chest pain

    -Dyspnea

    -Referred shoulder pain or hiccup

    -Basilar atelectasis or effusion

    -Diarrhea

    -Urinary frequency

  • Severe peritoneal sepsis with multiple organ failure may develop in patients with advanced cases

Laboratory Findings

• • Leukocytosis

  • Bacteremia

  • Abnormal liver profile, renal function tests, or ABG measurements

  • Elevated ESR and C-reactive protein levels

Imaging Findings

• • Abdominal x-ray: Suggest abscess in up to 50% of cases via nonspecific findings, such as

  • -Ileus pattern

    -Air-fluid levels

    -Soft-tissue mass

    -Free or mottled gas pockets

    -Effacement of preperitoneal or psoas outlines

    -Displacement of viscera

  • US

  • -Diagnose intra-abdominal abscesses in up to 80% of cases

    -Most useful when an abscess is suspected in the right upper quadrant

    -Bowel gas, stomas, and incisions interfere with the study

  • Water-soluble contrast study sensitive in detecting a perforated viscus

  • Abdominal pelvic CT scan with IV and PO contrast is the best diagnostic study with > 95% sensitivity, particularly in postoperative patients

  • -Percutaneous drainage procedures can often be performed at the same setting

• • Sterile fluid collection

  • Hematoma

  • Biloma

  • Urinoma

  • Neoplasm

  • Other common infectious/inflammatory sources that manifest with fever, leukocytosis, and abdominal pain:

  • -Pancreatitis

    -Pyelonephritis

    -Lower lobe pneumonia

    -Deep wound infection

  • Bacteremia/line sepsis

  • Evaluate for source of abscess:

  • -GI anastomotic leak

    -Perforated appendicitis

    -Perforated diverticulitis

    -Crohns enterocolitis

    -Perforated peptic ulcer

    -Pelvic inflammatory disease/tubo-ovarian abscess

• • CBC

  • Basic chemistries

  • Amylase and lipase

  • UA

  • Blood cultures

  • Sputum culture and Gram stain

  • Chest film

  • Abdominal x-ray

  • Abdominal pelvic CT scan with IV and PO contrast

When to Admit

• • All patients with an intra-abdominal abscess should be admitted (if not already) for drainage and initiation of IV antibiotics

When to Refer

• • Most patients with intra-abdominal abscesses should be managed by a general surgeon

  • Postoperative abscesses ideally should be addressed by the operative surgeon

• • IV antibiotic therapy may initially be attempted for small abscesses < 1-2 cm if the patient is clinically stable

  • Treatment of most abscesses consists of prompt and complete drainage, control of the primary cause, and adjunctive use of antibiotics

  • Percutaneous drainage is the preferred ...