0521779407-19 CUNY1086/Karliner 0 521 77940 7 June 6, 2007 17:50
Spontaneous Bacterial Peritonitis 1365Physical Signs
■fever, hypotension, tachycardia, abdominal tenderness, asterixis
■one-third without the classical signs
tests
■laboratory features: azotemia, peripheral leukocytosis, acidosis
■diagnostic paracentesis
➣cell countneutrophil (PMN) count≥250/mm (^3) presumed to be infection
➣culture
bedside inoculation of 10 mL of ascitic fluid into each of two
culture bottles
most infections are caused by Escherichia coli, streptococci
(mostly pneumococci), and Klebsiella, with only 1% contribu-
tion from anaerobes
➣gram stain
too insensitive for detecting spontaneous bacterial peritonitis
➣patients with neutrocytic ascites and meeting 2 of the following
3 criteria may have surgical peritonitis:
ascitic fluid total protein >1.0 gm/dL,
ascitic fluid glucose <50 mg/dL
ascitic fluid LDH level > upper limit of normal for serum
differential diagnosis
■spontaneous ascitic fluid infection is divided into subcategories:
➣spontaneous bacterial peritonitis (SBP)
elevated ascitic fluid PMN≥250 cells/mm(3), monomicrobial
ascitic fluid culture, and absence of surgical source of intra-
abdominal infection
➣monomicrobial non-neutrocytic bacterascites (MNB)
non-elevated ascitic fluid PMN≤250 cells per mm (^3) , monomi-
crobial ascitic fluid culture, and absence of surgical infection
early stage and common variant of SBP; progresses to SBP in
40% and resolve spontaneously in 60%
➣culture-negative neutrocytic ascites (CNNA)
elevated ascitic fluid PMN≥250 cells/mm3, negative ascitic
fluid culture, absence of surgical infection, absence of other
causes for elevated ascitic fluid PMN, and absence of any
antibiotics given within 30 days
■secondary bacterial peritonitis: ascitic fluid PMN≥250 cells/mm3,
positive ascitic fluid culture that is usually polymicrobial, and pres-
ence of intra-abdominal infection due to either free perforation of a
viscus or loculated abscess