In most cases, chest radiographic findings in patients with TP peritonitis are abnormal; active pulmonary disease is uncommon (< 30%). Results on Gram stain of ascitic fluid are rarely positive, and culture results may be falsely negative in up to 80% of patients. A peritoneal fluid protein level greater than 2.5 g/dL, a lactate dehydrogenase (LDH) level greater than 90 U/mL, or a predominantly mononuclear cell count of greater than 500 cells/μ L should raise suspicion of TP but have limited specificity for the diagnosis. Laparoscopy and visualization of granulomas on peritoneal biopsy specimens, as well as cultures (requires 4-6 wk), may be needed for the definitive diagnosis; however, empiric therapy should begin immediately.
Table 3. Microbiology of Primary, Secondary, and Tertiary Peritonitis (Open Table in a new window)
Peritonitis (Type) |
Etiologic Organisms |
Antibiotic Therapy (Suggested) |
|
Class |
Type of Organism |
||
Primary |
Gram-negative |
E coli (40%) K pneumoniae (7%) Pseudomonas species (5%) Proteus species (5%) Streptococcus species (15%) Staphylococcus species (3%) Anaerobic species (< 5%) |
Third-generation cephalosporin |
Secondary |
Gram-negative |
E coli Enterobacter species Klebsiella species Proteus species |
Second-generation cephalosporin Third-generation cephalosporin Penicillins with anaerobic activity Quinolones with anaerobic activity Quinolone and metronidazole Aminoglycoside and metronidazole |
Gram-positive |
Streptococcus species Enterococcus species |
||
Anaerobic |
Bacteroides fragilis Other Bacteroides species Eubacterium species Clostridium species Anaerobic Streptococcus species |
||
Tertiary |
Gram-negative |
Enterobacter species Pseudomonas species Enterococcus species |
Second-generation cephalosporin Third-generation cephalosporin Penicillins with anaerobic activity Quinolones with anaerobic activity Quinolone and metronidazole Aminoglycoside and metronidazole Carbapenems Triazoles or amphotericin (considered in fungal etiology) (Alter therapy based on culture results.) |
Gram-positive |
Staphylococcus species |
||
Fungal |
Candida species |
||
-
Peritonitis and abdominal sepsis. Diagnostic and therapeutic approach to peritonitis and peritoneal abscess.
-
Peritonitis and abdominal sepsis. A 48-year-old man underwent suprapubic laparotomy, right hemicolectomy, and gastroduodenal resection for right colon cancer invading the first portion of the duodenum. After surgery, the patient developed abdominal pain and distention. Computed tomography (CT) scanning was used to confirm an anastomotic dehiscence. Figure A shows a contrast-enhanced scan of the abdomen and pelvis that reveals multiple fluid collections, perihepatic ascites, and mild periportal edema. A collection of fluid containing an air-fluid level is visible anterior to the left lobe of the liver. A second collection is anterior to the splenic flexure of the colon. In figure B, a third fluid collection is present in the inferior aspect of the lesser space and in the transverse mesocolon. Figure C shows the pelvis with a collection of free fluid in the rectovesical pouch.
-
Peritonitis and abdominal sepsis. A 78-year-old man was admitted with a history of prior surgery for small bowel obstruction and worsening abdominal pain, distended abdomen, nausea, and obstipation. In figure A, a marked amount of portal venous gas within the liver, mesenteric venous gas, and pneumatosis intestinalis are consistent with ischemic small intestine. The superior mesenteric artery appears patent. The liver has a nodular contour consistent with cirrhosis. In figures B and C, markedly distended loops of small intestine containing fluid and air-fluid levels are consistent with a small bowel obstruction. No focal fluid collections are identified.
-
Peritonitis and abdominal sepsis. A 35-year-old man with a history of Crohn disease presented with pain and swelling in the right abdomen. In figure A, a thickened loop of terminal ileum is evident adherent to the right anterior abdominal wall. In figure B, the right anterior abdominal wall is markedly thickened and edematous, with adjacent inflamed terminal ileum. In figure C, a right lower quadrant abdominal wall abscess and enteric fistula are observed and confirmed by the presence of enteral contrast in the abdominal wall.
-
Peritonitis and abdominal sepsis. Gram-negative Escherichia coli.
Tables
Peritonitis (Type) |
Etiologic Organisms |
Antibiotic Therapy (Suggested) |
|
Class |
Type of Organism |
||
Primary |
Gram-negative |
E coli (40%) K pneumoniae (7%) Pseudomonas species (5%) Proteus species (5%) Streptococcus species (15%) Staphylococcus species (3%) Anaerobic species (< 5%) |
Third-generation cephalosporin |
Secondary |
Gram-negative |
E coli Enterobacter species Klebsiella species Proteus species |
Second-generation cephalosporin Third-generation cephalosporin Penicillins with anaerobic activity Quinolones with anaerobic activity Quinolone and metronidazole Aminoglycoside and metronidazole |
Gram-positive |
Streptococcus species Enterococcus species |
||
Anaerobic |
Bacteroides fragilis Other Bacteroides species Eubacterium species Clostridium species Anaerobic Streptococcus species |
||
Tertiary |
Gram-negative |
Enterobacter species Pseudomonas species Enterococcus species |
Second-generation cephalosporin Third-generation cephalosporin Penicillins with anaerobic activity Quinolones with anaerobic activity Quinolone and metronidazole Aminoglycoside and metronidazole Carbapenems Triazoles or amphotericin (considered in fungal etiology) (Alter therapy based on culture results.) |
Gram-positive |
Staphylococcus species |
||
Fungal |
Candida species |
||
