para>30% of patients are asymptomatic (1)[C].
Geriatric Considerations
Signs and symptoms are frequently absent, particularly in pediatric and elderly patients (1)[B].
PHYSICAL EXAM
- Tachycardia, fever, tachypnea, altered mental status
- Abdominal distention, ascites, abdominal wall guarding and rigidity, rebound tenderness, hypoactive/absent bowel sounds
DIFFERENTIAL DIAGNOSIS
- Liver disease: acute hepatitis, decompensated cirrhosis
- Luminal disease: abscess formation, ileus, volvulus, intussusception, mesenteric adenitis, pancreatitis, cholecystitis, malignancy, peritoneal carcinomatosis
- Extraluminal disease: ruptured ectopic pregnancy, tubo-ovarian abscess, PID, severe UTI, and/or pyelonephritis
- Systemic disease: tuberculosis, pneumonia, MI, porphyria, SLE
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
ALERT
Early diagnosis is essential to reduce mortality. Paracentesis should be performed in any patient with new ascites, including suspected SBP (5)[B].
- Immediate evaluation
- Perform paracentesis, blood, and urine cultures before administration of antibiotics (1,5)[B].
- Ascitic fluid studies should minimally include culture (use aerobic and anaerobic blood culture bottles), Gram stain, cell count with differential, and albumin (1)[B]; if assessing for secondary peritonitis also include LDH, total protein and glucose.
ALERT
Lab interpretation: Ascitic fluid culture is negative in up to 50% of patients with SBP (1)[A].
- SBP: bacterascites and ascitic fluid PMN >250 cells/mm3
- Culture-negative neutrocytic ascites: negative ascites culture, ascitic fluid PMN >250 cells/mm3
- Nonneutrocytic bacterascites: positive ascites culture, ascitic fluid PMN <250 cells/mm3
- Secondary peritonitis: PMN >250 cells/mm3 on ascitic fluid analysis, with any of the following criteria:
- Polymicrobial culture or two of the following: ascitic fluid total protein >1 g/dL, glucose <50 mg/dL, or LDH >225 mU/mL. Sensitivity for perforation 96%, sensitivity for nonperforation secondary peritonitis 50% (5)[B]
- Secondary peritonitis with perforation is likely with alkaline phosphatase >240 U/l or CEA >5 ng/mL, sensitivity 92% (5)[B].
ALERT
Imaging: Criteria or clinical suspicion for secondary peritonitis necessitates emergent CT scan. CT diagnostic for secondary peritonitis in 85% (5)[B].
- Ultrasound or CT scan with enteral and IV contrast shows intra-abdominal mass, ascites, abscess, or extravasation of contrast in secondary peritonitis
- Abdominal or chest x-ray may show free air in peritoneal cavity, large/small bowel dilatation, intestinal wall edema in secondary peritonitis.
Follow-Up Tests & Special Considerations
- If asymptomatic bacterascites, recent antibiotic exposure, nosocomial atypical organism, or no clinical improvement, repeat paracentesis in 48 hours to resolution, defined as decrease in PMNs of 25% or negative cultures (1)[C].
- In hemorrhagic ascites, PMN count can be corrected by subtracting 1 PMN per 250 RBCs (3)[A].
TREATMENT
GENERAL MEASURES
- For SBP, control the effects of cirrhosis/ascites with salt restriction, spironolactone +/ ’ furosemide, albumin infusion after large volume paracentesis, and/or lactulose for encephalopathy (5)[A].
- Avoid nephrotoxic medications (e.g., NSAIDs) or other renal insults (5)[C].
MEDICATION
- SBP empiric first-line treatment
- Community-acquired SBP w/o recent ²-lactam antibiotic use: 3rd-generation cephalosporins, preferably cefotaxime, 2 g IV q8h for 5 days (5)[A]
- SBP in absence of previous quinolone use/prophylaxis, vomiting, shock, hepatic encephalopathy, or serum creatinine >3 mg/dL: ofloxacin 400 mg PO can be substituted for cefotaxime (5)[B].
- Nosocomial SBP or recent ²-lactam antibiotic: Empiric therapy based on local susceptibility of patients with cirrhosis for resistant bacteria (e.g., ESBL Enterobacteriaceae, MRSA) (6)[B]
- Symptomatic bacterascites with PMN count <250 cells/mm3: cefotaxime 2 g IV q8h while awaiting sensitivities (5)[B]
- Second-line antibiotic regimens include fluoroquinolones (levofloxacin), piperacillin/tazobactam, or vancomycin (5)[C].
- SBP with renal or hepatic impairment (serum creatinine >1 mg/dL, BUN >30 mg/dL, or total bilirubin >4 mg/dL): Add albumin 1.5 g/kg within 6 hours and 1 g/kg on day 3 (1)[A],(5)[B].
- Secondary bacterial peritonitis
- Empiric broad spectrum antibiotic coverage for polymicrobial infection; IV cefoxatime or other 3rd- to 4th-generation cephalosporin plus metronidazole is one option for an initial regimen.
- In peritoneal dialysis associated infection, intraperitoneal route superior to IV (6)[A]
- Tertiary bacterial peritonitis
- If no unrepaired perforations or leaks, conservative medical management. This includes antibiotics (guided by prior susceptibilities if available) and early enteral nutrition to prevent atrophy and maintain immunocompetence (2)[B].
- In recurrent or persistent peritoneal dialysis associated infection, removal of the PD catheter is warranted (6)[A].
SURGERY/OTHER PROCEDURES
- SBP
- Secondary bacterial peritonitis
- Emergent surgical management, including source control with open laparotomy to repair any perforated viscus and eradicate infected material, is first-line treatment (2)[A],(5)[B].
- Tertiary bacterial peritonitis
- If no unrepaired perforations or leaks, additional surgery for severe abdominal infection is correlated with deterioration and significant mortality (2).
ALERT
Mortality of SBP approaches 80% if the patient receives unnecessary exploratory laparotomy; conversely, mortality of secondary bacterial peritonitis approaches 100% if not treated surgically (1,3).
INPATIENT CONSIDERATIONS
Admission Criteria/Initial Stabilization
- Acute peritonitis typically warrants inpatient admission.
- In patients with cardiogenic or septic shock, invasive monitoring with early goal-directed fluid therapy
- Patients who present with peritonitis can be severely hypovolemic. In these cases, volume resuscitation is critical. In patients with significant renal or hepatic dysfunction, albumin decreases mortality (1)[A],(5)[B].
- Cirrhotic patients often take ²-blockers as part of their outpatient regimen, but during an episode of SBP ²-blockers increase mortality, hepatorenal syndrome, and hospital stay in SBP patients (5)[B]
- Nasogastric tube placement can prevent aspiration in patients with vomiting or GI bleeding.
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Patient Monitoring
Normalization of vital signs with resolution of leukocytosis indicates improvement.
- SBP: If follow-up paracentesis is performed after 48 hours to evaluate resolution, PMN decrease >25% is expected.
- Development of leukopenia indicates immune exhaustion and poor prognosis.
DIET
- NPO, total parental nutrition as necessary
- Resume enteral feeding after return of bowel function
- Sodium restriction can reduce future ascites (3)[A].
PROGNOSIS
- SBP
- For inpatients with first episode of SBP, mortality ranges from 10% to 50% (3).
- Prognosis is improved if antibiotics are started early, prior to onset of shock or renal failure.
- Strongest negative prognostic indicator is renal insufficiency.
- Other poor prognostic factors include nosocomial acquisition, old age, high Child-Pugh-Turcotte or MELD score, malnutrition, malignancy, peripheral leukopenia, and antibiotic resistance (3).
- Patients with prior SBP have 1-year recurrence rate of 40 " 70% and 1-year mortality of 31 " 93% (1,3).
- Secondary bacterial peritonitis:
- In-hospital mortality of treated patients is 67% (4).
- Mortality approaches 100% if not treated surgically, especially if secondary to perforation (2,4).
- Prognosis is worse in perforated etiologies.
COMPLICATIONS
- Renal failure, liver failure, encephalopathy, coagulopathy
- Secondary infection, iatrogenic infection, abscess, fistula formation, abdominal compartment syndrome
- Sepsis/septic shock, cardiovascular collapse, adrenal insufficiency, respiratory failure, ARDS
REFERENCES
11 Alaniz C, Regal RE. Spontaneous bacterial peritonitis: a review of treatment options. P T. 2009;34(4):204 " 210.22 Panhofer P, Izay B, Riedl M, et al. Age, microbiology and prognostic scores help to differentiate between secondary and tertiary peritonitis. Langenbecks Arch Surg. 2009;394(2):265 " 271.33 Wiest R, Krag A, Gerbes A. Spontaneous bacterial peritonitis: recent guidelines and beyond. Gut. 2012;61(2):297 " 310.44 Soriano G, Castellote J, Alvarez C, et al. Secondary bacterial peritonitis in cirrhosis: a retrospective study of clinical and analytical characteristics, diagnosis and management. J Hepatol. 2010;52(1):39 " 44.55 Runyon B; AASLD. Introduction to the revised American Association for the Study of Liver Diseases practice guideline management of adult patients with ascites due to cirrhosis 2012. Hepatology. 2013;57(4):1651 " 1653.66 Ballinger A, Palmer SC, Wiggins KJ, et al. Treatment for peritoneal dialysis-associated peritonitis. Cochrane Database Syst Rev. 2014;(4):CD005284.
ADDITIONAL READING
- Bajaj JS, O 'Leary JG, Wong F, et al. Bacterial infections in end-stage liver disease: current challenges and future directions. Gut. 2012;61(8):1219 " 1225.
- Cheong HS, Kang CI, Lee JA, et al. Clinical significance and outcome of nosocomial acquisition of spontaneous bacterial peritonitis in patients with liver cirrhosis. Clin Infect Dis. 2009;48(9):1230 " 1236.
- Deshpande A, Pasupuleti V, Thota P, et al. Acid-suppressive therapy is associated with spontaneous bacterial peritonitis in cirrhotic patients: a meta-analysis. J Gastroenterol Hepatol. 2013;28(2):235 " 242.
- Ghassemi S, Garcia-Tsao G. Prevention and treatment of infections in patients with cirrhosis. Best Pract Res Clin Gastroenterol. 2007;21(1):77 " 93.
- Jain P. Spontaneous bacterial peritonitis: few additional points. World J Gastroenterol. 2009;15(45):5754 " 5755.
- Koulaouzidis A, Bhat S, Karagiannidis A, et al. Spontaneous bacterial peritonitis. Postgrad Med J. 2007;83(980):379 " 383.
- Koulaouzidis A, Bhat S, Saeed AA. Spontaneous bacterial peritonitis. World J Gastroenterol. 2009;15(9):1042 " 1049.
- Mandorfer M, Bota S, Schwabl P, et al. Nonselective ² blockers increase risk for hepatorenal syndrome and death in patients with cirrhosis and spontaneous bacterial peritonitis. Gastroenterology. 2014;146(7):1680.e1 " 1690.e1.
SEE ALSO
Appendicitis, Acute; Cirrhosis of the Liver; Diverticular Disease; Peptic Ulcer Disease
CODES
ICD10
- K65.0 Generalized (acute) peritonitis
- K65.2 Spontaneous bacterial peritonitis
- K65.8 Other peritonitis
- K65.9 Peritonitis, unspecified
- K65.1 Peritoneal abscess
ICD9
- 567.21 Peritonitis (acute) generalized
- 567.23 Spontaneous bacterial peritonitis
- 567.89 Other specified peritonitis
- 567.9 Unspecified peritonitis
- 567.22 Peritoneal abscess
- 567.29 Other suppurative peritonitis
SNOMED
- 67602004 Acute peritonitis
- 11836002 Primary bacterial peritonitis (disorder)
- 31860008 Acute bacterial peritonitis
- 213293008 Aseptic peritonitis (disorder)
CLINICAL PEARLS
- Maintain a high index of suspicion for SBP in cirrhotic patients with ascites. SBP occurs in preexisting ascites and carries a high mortality, especially if presenting with GI bleed.
- Early diagnosis and treatment reduces mortality.
- Paracentesis is necessary to diagnose SBP.
- Emergent CT scan should be performed if there is suspicion of secondary bacterial peritonitis.
- Distinguishing SBP from secondary bacterial peritonitis is essential, as SBP treatment consists of antibiotic therapy whereas secondary bacterial peritonitis necessitates emergent surgical intervention.
- Renal function is an important prognostic indicator for SBP. Albumin administration decreases the incidence of renal failure and mortality in patients with renal or hepatic impairment or large-volume paracentesis.