Peritonitis

Background

• Inflammation of serosal membrane lining abdominal cavity and intraabdominal organ
• Infectious or sterile (mechanical, chemical)
• Primary: Hematogenous, spontaneous bacterial peritonitis (SBP)
• Secondary: Perforation or trauma, most common
• Tertiary: Persistent/recurrent infection

Clinical Features

• Abdominal pain or discomfort
• Abdominal distention, wall tenderness, rigidity
• Anorexia and nausea
• Guarding or rebound
• Sepsis
• Signs of liver failure
• Spontaneous bacterial peritonitis
  • Fever and chills
  • Abdominal pain or discomfort
  • Worsening or unexplained encephalopathy
  • Diarrhea
  • Ascites
  • Worsening or new-onset renal failure
  • Ileus

Differential Diagnosis

• Perforation
• Chronic peritoneal dialysis
• Neoplasm
• Pyelonephritis
• Empyema
• Rectus hematoma
• Intestinal incarceration, hernia
• Appendicitis
• Mesenteric ischemia
• Abdominal aneurysm

Workup

• Clinical diagnosis
• CBC (leukocytosis), chem, coags, albumin
• Other test: LFT, lipase, UA, Stool sample
• Abdominal Xray (supine, upright, lateral decubitus)- free air?
• US, CT a/p
• Diagnostic paracentesis to r/o SBP: PMN ≥ 250 cells/mm³

Management

• Fluid resuscitation
• Surgical consult
• IR consult if requiring abscess drainage

Antibiotics

Moderate

• Metronidazole 500mg IV q8hrs PLUS
  • Ceftriaxone 1g IV once daily OR
  • Ciprofloxacin 400mg IV q12hrs OR
  • Cefazolin 1g (30mg/kg) IV q8hrs OR
  • Levofloxacin 750mg IV once daily

Severe

• Piperacillin/Tazobactam 4.5g (80mg/kg) IV q8hrs OR
• Metronidazole 500mg IV q8hrs PLUS
  • Cefepime 2g IV once daily OR
  • Ciprofloxacin 400mg IV q12hrs OR
  • Levofloxacin 750mg IV once daily
• Meropenem 1g (20mg/kg) IV q8hrs OR
• Doripenem 500mg IV q8hrs OR
• Aztreonam 2g (30mg/kg) IV q8hrs + Metronidazole 500mg IV q8hrs

See Also

• Abdominal pain

Sources

Daley BJ, et al. (2014, Sep 25). Peritonitis and Abdominal Sepsis. eMedicine. Retrieved 12/25/2014 from http://emedicine.medscape.com/article/180234-overview