Spontaneous Bacterial Peritonitis (SBP) & Ascitic

7/28/2019 Spontaneous Bacterial Peritonitis (SBP) & Ascitic

1/15

Spontaneous Bacterial

Peritonitis (SBP) & Ascitic FluidInfection


2/15

Spontaneous bacterial peritonitis (SBP) is an acute bacterial infection of

ascitic fluid.

Patients with cirrhosis and ascites carry a 10% annual risk of ascitic fluid

infection.

Of patients with cirrhosis who have SBP, 70% are Child-Pugh class C. In

these patients, the development of SBP is associated with a poor long-term

prognosis.


3/15

Pathophysiology

Bacterial seeding of ascitic fluid is the principle of ascitic fluid

infection. The most two likely roots are translocation and

hematogenous spread

In cirrhotic patients, bacterial translocation was significantly

increased only in Child C patients (30%) compared with 8% in Child

B and 3% in Child A patients. In fact, the only independent

predictor of translocation was Child-Pugh class.


4/15

Predisposing factor may be :

Intestinal bacterial overgrowth (attributed to decreased intestinal

transit time)

Impaired phagocytic function

Low serum and ascites complement levels

Decreased activity of the reticuloendothelial system


5/15

Etiologic agents (>90% intestinal flora)

Three forth of infections are due to aerobic gram-negative

organisms (50% of these being Escherichia coli )

One fourth are due to aerobic gram-positive organisms

(19% streptococcal species). However, recent data suggest the

percentage of gram-positive infections may be increasing due to

quinolone resistance among gram-positive bacteria.

Anaerobic organisms are rare (1%) because of the high

oxygen tension of ascitic fluid.


6/15

Risk factors for ascitic fluid infection

severity of liver disease

deficient AF bactericidal activity (AF total protein


7/15

Clinical presentation and diagnosis of ascitic fluid infection

A broad range of symptoms and signs are seen in SBP. A high index

of suspicion must be maintained when caring for patients with

ascites, particularly those with acute clinical deterioration.Completely asymptomatic cases in as many as 30% of patients.

Fever and chills occur in as many as 80% of patients.

Abdominal pain or discomfort is found in 70% of patients.

Worsening or unexplained encephalopathy

Diarrhea


8/15

Ascites that does not improve following administration of diuretic

medication

Worsening or new-onset renal failure

Ileus

Abdominal tenderness (50%) .

Hypotension (5-14%)

Signs of hepatic failure such as jaundice and angiomata


9/15

Diagnostic paracentesis and direct inoculation of routine blood

culture bottles at the bedside with 10 mL of ascitic fluid must be

performed. The results of aerobic and anaerobic bacterial

cultures , used in conjunction with the cell count , prove the most

useful in guiding therapy for those with SBP.


10/15

An ascitic fluid neutrophil count of >500 cells/mL is the single

best predictor of SBP, with a sensitivity of 86% and specificity of

98%. Lowering the ascitic fluid neutrophil count to >250

cells/mL results in an increased sensitivity of 93% but a lower

specificity of 94%.


11/15

Combining these results yields the following subgroups:

SBP exists when the polymorphonuclear neutrophil (PMN)

count is >250 cells/mL in conjunction with a positivebacterial culture result.

Culture-negative neutrocytic ascites (probable SBP)

exists when the ascitic fluid culture results are negative, but

the PMN count is >250 cells/mL. It may be the result of poor

culturing techniques or late-stage resolving infection.

Nonetheless, these patients should be treated just as

aggressively as those with positive culture results.


12/15


13/15

Variants of ascitic fluid infectionsinclude:

AF PMNs (per mm 3)AF cultureVariant of ascitic fluid (AF) infection

250monomicrobialSpontaneous bacterial peritonitis (SBP)

250negativeCulture-negative neutrocytic ascites(CNNA)

250 polymicrobialSecondary bacterial peritonitis*

< 250monomicrobialMonomicrobial nonneutrocytic bacterascites (MNB)

< 250 polymicrobialPolymicrobial bacterascites**

*a surgically treatable intraabdominal focus of infection exists

** a rare

iatrogenic

variant occurring as a result of accidental intestinalpuncture during paracentesis


14/15

Other studies of ascitic fluid to be considered

Cytology

Lactate : An ascites lactate level of >25 mg/dL was found to be

100% sensitive and specific in predicting active SBP in a

retrospective analysis.

pH: In the same study, the combination of an ascites fluid pH of

500 cells/mL was 100% sensitive and

96% specific.

Blood and urine cultures should be obtained in all patients

suspected of having SBP.


15/15

Spontaneous Bacterial Peritonitis (SBP) & Ascitic

Documents

Transcript of Spontaneous Bacterial Peritonitis (SBP) & Ascitic