Diagnosis

Peritonitis

Etiology

Cause [ziz][p6o][fmz][jy7]

1. Primary spontaneous bacterial peritonitis: acute bacterial infection of ascitic fluid

2. Secondary (surgical/infectious) peritonitis: E coli, K pneumoniae, S aureus, typhoid

   • Esophagus:

     • Boerhaave syndrome

     • Tumor perforation

     • Trauma

     • Iatrogenic

   • Stomach/Duodenum:

     • Peptic ulcer perforation

     • Tumor perforation

     • Trauma

     • Iatrogenic

   • Biliary tract:

     • Cholecystitis

     • Stone perforation from gallbladder

     • Choledochal cyst

   • Small bowel:

     • Ischemic bowel

     • Incarcerated hernia

     • Closed loop obstruction

     • Crohn disease

     • Tumor perforation

     • Meckel diverticulum

     • Trauma

   • Large bowel:

     • Ischemic bowel

     • Diverticulitis

     • Tumor perforation

     • Ulcerative colitis

     • Crohn disease

     • Appendicitis

     • Colonic volvulus

     • Trauma

     • Iatrogenic: anastomotic leak, endoscopic perforation, enterotomy

   • Pancreatitis

   • Liver abscess

   • Pelvic inflammatory disease

   • Peritoneal dialysis

3. Sterile peritonitis: mechanical (fish bone, glass, gallstone), chemical (bile, gastric acid, pancreas, blood, enema)

4. Tertiary peritonitis: persistent or recurrent infection after adequate initial therapy in comorbid immunocompromised patients

Pathophysiology [jy7]

1. The physiologic response is determined by:

   • The virulence of the contaminant

   • The size of the inoculum

   • The immune status and overall health of the host

2. Primary spontaneous bacterial peritonitis:

   • Translocation across the gut wall

   • Mesenteric lymphatics

   • Hematogenous seeding

3. Secondary peritonitis: Perforated viscus --> spillage of luminal contents --> bacterial toxins --> cytokines --> cellular and humoral cascades --> cellular damage

4. Clinical presentation:

   • Pain

   • Fever

   • Diarrhea

   • Renal failure

   • Ileus

Complications [jy7]

• Tertiary peritonitis

• Intra-abdominal sepsis

• Septic shock

• Multi organ failure

• Enterocutaneous fistula

• Abdominal compartment syndrome

Epidemiology

Incidence per 100.000 [n8t][9av][ohs][fmz][cb3][ieu][ziz][p6o]

Approach

• Blood test

• Blood gas

• Blood culture

• Urine stix

• Urine culture

• Abdominal x-ray

• Ultrasound abdomen

• CT abdomen

• MRI

• Diagnostic peritoneal lavage/paracentesis (cell count, differential, culture, cytology, lactate, pH)

• Stool Sample

Treatment

1. Supportive therapy: [jy7]

   • Fluid therapy

   • Correction of electrolytes

   • Hemodynamic, pulmonary, and renal support

   • Nutrition and metabolic support

   • Inflammatory response modulation therapy

   • Antibiotics: Ceftriaxone + Metronidazole

2. Nonoperative interventions [jy7]

   • Percutaneous abscess drainage

   • Percutaneous and endoscopic stent placements

3. Explorative laparotomy [ssk]

   • Lavage

   • Drainage

   • Removing contaminated dialysis catheter

   • Bowel resection

   • Ileostomy/Colostomy

   • Gastroraphy

Differential diagnoses

Acute intermittent porphyria, Acute mesenteric ischemia, Acute pancreatitis, Aortic dissection, Appendicitis, Carcinomatosis, Cholecystitis, Chylous peritonitis, Cirrhosis, Colorectal cancer, Crohn disease, Diverticulitis, Endometriosis, Eosinophilic peritonitis, Esophageal perforation, Familial mediterranean fever, Femoral hernia, Fungal infection, Gastric cancer, Henoch-Schönlein purpura, Incisional hernia, Infectious colitis, Ischemic colitis, Kohlmeier-Degos disease, Liver abscess, Meckels diverticulum, Ovarian torsion, Parasitic infestations, Pelvic inflammatory disease, Perforated ulcer, Peritoneal encapsulation, Peritoneal lymphangiectasis, Polyarteritis nodosa, Portal hypertension, Primary mesothelioma, Pyelonephritis, Rectus sheath hematoma, Ruptured aortic aneurysm, Sarcoidosis, Sclerosing peritonitis, Splenosis, Systemic lupus erythematosus, Ulcerative colitis, Umbillical hernia, Urinary retention, Urinary tract infection, Volvulus, Whipple's disease