Liver metastasis presenting as pneumoperitoneum.

Abstract: A 63-year-old man presented to the emergency department with sudden-onset abdominal pain. Chest radiography demonstrated pneumoperitoneum. At surgery, the source was found to be a ruptured hepatic abscess. Cultures grew Clostridium perfringens, and biopsies confirmed metastasis of a previously resected pancreatic cancer. We document this rare cause of pneumoperitoneum and briefly review the literature on liver abscess as it relates to metastatic cancer.

Key Words: Clostridium perfringens, liver abscess, pneumoperitoneum.

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Case Report

A 63-year-old man was seen in the emergency department complaining of sudden-onset abdominal pain approximately 18 hours previously. The pain was generalized and associated with vomiting, fever, and chills. He had been asymptomatic before the onset of pain. His temperature was 96.6[degrees]F; blood pressure, 138/70 mm Hg; and heart rate, 135 bpm. On physical examination, his abdomen was distended and tense with generalized rebound tenderness. His white blood count was 13,500/[micro]L with 19% bands. Basic chemistry revealed an anion gap of 29. Chest radiography showed pneumoperitoneum (Fig. 1).

The patient was 8 months status post Whipple procedure. Pathology was consistent with stage III, grade III pancreatic adenocarcinoma. He had undergone chemotherapy with 5-FU as well as radiation treatment. A CT scan was performed 1 week before presentation in the emergency department, and this showed a possible metastasis in the right lobe of the liver (Fig. 2).

After fluid resuscitation, the patient was taken for exploratory laparotomy under presumptive diagnosis of perforated viscous. Extensive examination of the abdomen revealed no evidence of perforation. Purulent fluid draining from the right upper quadrant led to the detection of a large perforated liver abscess. Cultures and biopsy specimens were taken, the area was irrigated, and drains were placed.

The patient initially did well after surgery. Cultures grew Klebsiella pneumoniae, Enterobacter aerogenes, Enterococcus, Group F Streptococcus, and Clostridium perfringens. The liver biopsy specimen was positive for metastatic adenocarcinoma. The patient was sent home on postoperative day 10 with drains in place. He was readmitted and again discharged with a new antibiotic regimen. Given the grave prognosis of his metastatic disease, further aggressive measures were not taken, and he died at home approximately 1 month after his initial presentation.

Discussion

Pyogenic liver abscess is a well-described disease process. Inciting factors include (1) ascending biliary infection (cholangitis, biliary obstruction), (2) direct extension of an abdominal or thoracic infection (appendicitis, diverticulitis), (3) portal bacteremia, (4) systemic sepsis with hematogenous spread, and (5) blunt or penetrating trauma.

A less common underlying cause is infection of a liver metastasis. This process makes up only 3 to 6% of cases of hepatic abscess and may be either spontaneous or a complication secondary to chemoembolization. (1-5) There appears to be no relation to the type of primary tumor. Liver abscess formation has been described in relation to leukemia, lymphoma, hepatoma, pancreatic, colon, biliary, and esophageal cancers. (4,6-8)

[FIGURE 1 OMITTED]

Approximately one third to one half of liver abscesses contain anaerobic bacteria, and 10 to 20% contain air. In relation to tumors, the majority of cases have isolated Clostridium septicum, although many others have been described. (6-8) Debate exists as to whether or not septicum is a normal commensal organism, but it is ubiquitous in the environment, possibly explaining its prevalence in tumor abscesses. (1,9) C perfringens has been reported once, after chemoembolization of a bile duct cancer metastasis. (1)

[FIGURE 2 OMITTED]

Rupture of a pyogenic abscess is uncommon. One series of 424 abscesses reported a rupture rate of 5.4%, with an associated mortality rate of 27.8%. (4) Rupture followed by gross pneumoperitoneum is sparsely reported. (4,10-12)

Conclusion

Our case documents two rare occurrences: infection of a liver abscess by C perfringens, and rupture of a liver abscess causing gross pneumoperitoneum. Anaerobic liver abscess can form when a tumor necroses, either spontaneously or therapeutically, providing an ideal milieu for anaerobic bacteria. This is a highly aggressive infection, and when combined with the mortality of metastatic disease, this condition carries a very grave prognosis.

Accepted October 4, 2004.

References

1. Eckel F, Lersch C, Juber W, et al. Multimicrobial sepsis including Clostridium perfringens after chemoembolization of a single liver metastasis from common bile duct cancer. Digestion 2000;62:208-212.

2. Gerson LB, Pont A, Cummins RT. Clostridial bacteremia and death following chemoembolization for hepatocellular carcinoma. J Vasc Interv Radiol 1994;5:167-170.

3. De Baire T, Roche A, Amenabar JM, et al. Liver abscess formation after local treatment of liver tumors. Hepatology 1996;23:1436-1440.

4. Chou F-F, Sheen-Chen S-M, Lee T-Y. Rupture of pyogenic liver abscess. Am J Gastroenterol 1995;90:767-770.

5. Trump DL, Fahnestock R, Cloutier CT, Dickman MD. Anaerobic liver abscess and intrahepatic metastases: a case report and review of the literature. Cancer 1978;41:682-686.

6. Koransky JR, Stargel MD, Dowell VR. Clostridium septicum bacteremia: its clinical significance. Am J Med 1979;66:63-66.

7. Kolbeinsson ME, Holder WD, Aziz S. Recognition, management, and prevention of Clostridium septicum abscess in immunosuppressed patients. Arch Surg 1991;126:642-645.

8. Alpem RJ, Dowell VR. Clostridium septicum infections and malignancy. JAMA 1969;209:385-388.

9. D'Orsi CJ, Ensminger W, Smith E, Lew M. Gas-forming intrahepatic abscess: a possible complication of arterial infusion chemotherapy. Gastrointest Radiol 1979;4:157-161.

10. Urban BA, McCommick R, Fishman E, et al. Fulminant Clostridium septicum infection of hepatic metastases presenting as Pneumoperitoneum. Am J Roent 2000;174:962-964.

11. Salky BA, Kaynon A, Bauer JJ, et al. Ruptured hepatic abscess: a rare cause of spontaneous pneumoperitoneum. Am J Gastroenterol 1982;77:880-881.

12. Lee T-Y, Wan Y-L, Tsai C-C. Gas-containing liver abscess: radiological findings and clinical significance. Abdom Imaging 1994;19:47-52.

RELATED ARTICLE: Key Points

* Liver abscess is a complication of metastatic cancer, which carries a high mortality rate.

* Although many liver abscesses contain anaerobic bacteria and air, rupture causing pneumoperitoneum is exceedingly rare.

John Fondran, MD, and Gary B. Williams, MD

From the Department of Surgery, Akron City Hospital, Summa Health System, Akron, OH.

Reprint requests to Dr. John Fondran, Department of Surgery, Akron City Hospital, 525 East Market Street, Akron, OH 44309-2090. Email: [e-mail]