You are in: eMedicine Specialties > General Surgery > Abdomen Pyogenic Hepatic AbscessesArticle Last Updated: Mar 22, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 11
  Author: Mohamed Akoad, MD, Liver Transplant Surgeon, Division of Hepatobiliary and Liver Transplantation, Department of Surgery, Veterans Administration Pittsburgh Healthcare System Coauthor(s): Richard W Golub, MD, FACS, Consulting Surgeon, Sarasota Memorial Hospital and Doctors Hospital; Consulting Surgeon, Intercoastal Medical Group Editors: Alex Jacocks, MD, Program Director, Professor, Department of Surgery, University of Oklahoma School of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; David L Morris, MD, PhD, Professor, Department of Surgery, St George Hospital, University of New South Wales, Australia; Paolo Zamboni, MD, Professor of Surgery, Chief of Day Surgery Unit, Chair of Vascular Diseases Center, University of Ferrara, Italy; John Geibel, MD, DSc, MA, Professor, Department of Surgery, Section of Gastrointestinal Medicine and Department of Cellular and Molecular Physiology, Yale University School of Medicine; Director of Surgical Research, Department of Surgery, Yale-New Haven Hospital Author and Editor Disclosure Synonyms and related keywords: liver abscess, biliary disease, choledocholithiasis, malignant tumors, benign tumors, post-surgical strictures, postsurgical strictures, biliary-enteric anastomoses, choledochoduodenostomy, portal pyemia, appendicitis, pylephlebitis, diverticulitis, inflammatory bowel disease, proctitis, systemic septicemia, pyogenic bacteria INTRODUCTIONSection 2 of 11
  Pyogenic hepatic abscesses are uncommon conditions that present both diagnostic challenges and therapeutic challenges to physicians, and, if left untreated, they are invariably fatal. History of the ProcedureLiver abscesses have been recognized since the age of Hippocrates. In 1883, Koch described the amoebae as a cause of liver abscess. In 1938, Ochner and Debakey published the largest series of pyogenic and amebic liver abscesses in the literature. Over the past 2 decades, percutaneous drainage has become a useful therapeutic option. FrequencyThe incidence of pyogenic liver abscess remained unchanged over the past 70 years. In the United States, the incidence of pyogenic liver abscess is estimated to be 8-15 cases per 100,000 population. This figure is considerably higher in countries where health care is not readily available. The male-to-female ratio is approximately 2:1 in recent studies, and the problem occurs most commonly in the fourth to sixth decade of life. EtiologyBiliary disease Biliary disease accounts for 21-30% of reported cases. Extrahepatic biliary obstruction leading to ascending cholangitis and abscess formation is the most common cause and is usually associated with choledocholithiasis, benign and malignant tumors, or postsurgical strictures. Biliary-enteric anastomoses (choledochoduodenostomy or choledochojejunostomy) have also been associated with a high incidence of liver abscesses. Biliary complications (eg, stricture, bile leak) after liver transplantation are also recognized causes of pyogenic liver abscesses. Infection via the portal system (portal pyemia) The infectious process originates within the abdomen and reaches the liver by embolization or seeding of the portal vein. With the liberal use of antibiotics for intra-abdominal infections, portal pyemia is now a less frequent cause of pyogenic liver abscesses but still accounts for 20% of cases. Appendicitis and pylephlebitis are the predominant causes. However, any source of intra-abdominal abscess, like acute diverticulitis, inflammatory bowel disease, and perforated viscus, can lead to portal pyemia and hepatic abscesses. Hematogenous (via the hepatic artery) This infectious process results from seeding of bacteria into the liver in cases of systemic bacteremia from bacterial endocarditis, urinary sepsis, or following intravenous drug abuse. Blunt or penetrating trauma and liver necrosis from inadvertent vascular injury during laparoscopic cholecystectomy are recognized causes of liver abscess. Cryptogenic No cause is found in approximately half the cases. However, the incidence is increased in patients with diabetes or metastatic cancer. Patients with repeated cryptogenic liver abscess should undergo biliary and gastrointestinal evaluation. PathophysiologyPyogenic bacteria can gain access to the liver by direct extension from contiguous organs or through the portal vein or hepatic artery. Hepatic clearance of bacteria via the portal system appears to be a normal phenomenon in healthy individuals; however, organism proliferation, tissue invasion, and abscess formation can occur with biliary obstruction, poor perfusion, or microembolization. Microbiology The organisms isolated most often are included below. Most abscesses contain more than one organism and frequently are of biliary or enteric origin. Blood culture results are positive in 33-65% of cases, with positive results from abscess cultures reported in 73-100% of series. Escherichia coli is the most common organism isolated in western series, while Klebsiella pneumoniae has recently emerged as a common isolate in patients with diabetes in Taiwan. The most common microorganisms isolated from blood and abscess cultures are as follows:
ClinicalThe clinical presentation of liver abscess is insidious; many patients have symptoms for weeks prior to presentation. Fever and right upper quadrant pain are the most common complaints. Pain is reported in as many as 80% of patients and may be associated with pleuritic chest pain or right shoulder pain. Symptoms are often misdiagnosed as acute cholecystitis. Fever occurs in 87-100% of patients and is usually associated with chills and malaise. Anorexia, weight loss, and mental confusion are also common symptoms. Physical examination findings are most notable for right upper quadrant tenderness. Hepatomegaly, liver mass, and jaundice are also common. Occasionally, patients may present with rales, pleural effusion, friction rub, or pulmonary consolidation. Rarely, patients are admitted with sepsis and peritonitis from intraperitoneal rupture of the abscess. The following table summarizes the signs and symptoms of pyogenic liver abscess. Symptoms and Signs of Pyogenic Liver Abscess
INDICATIONSSection 3 of 11
Nowadays, most liver abscesses are treated with antibiotics and catheter drainage under ultrasonographic or CT guidance. The 5 indications for surgical drainage are as follows:
CONTRAINDICATIONSSection 4 of 11
Relative contraindications to surgery include the following:
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Lab Studies
Imaging Studies
Diagnostic Procedures
TREATMENTSection 6 of 11
Medical therapyThe most dramatic change in the treatment of pyogenic liver abscess has been the emergence of CT-guided drainage. Prior to this modality, open surgical drainage was the treatment most often employed, with mortality rates as high as 70%. If the abscess is multiloculated, multiple catheters might be needed to achieve adequate drainage. The current accepted approach includes 3 steps, as follows:
Antibiotic therapy Diagnostic aspiration should be performed as soon as possible. The antimicrobial agent should provide adequate coverage against aerobic gram-negative bacilli, microaerophilic streptococci, and anaerobic organisms, including Bacteroides fragilis. Usually, a combination of 2 or more antibiotics is used. Metronidazole and clindamycin have wide anaerobic coverage and provide excellent penetration into the abscess cavity. A third-generation cephalosporin or an aminoglycoside provides excellent coverage against most gram-negative organisms. Fluoroquinolones are an acceptable alternative in patients who are allergic to penicillin. Percutaneous drainage Diagnostic aspiration should be performed as soon as the diagnosis is made. It can be performed under ultrasonographic or CT guidance and is usually followed by placement of a drainage catheter. Once positioned, the catheter should be irrigated with isotonic sodium chloride solution and placed to allow gravity drainage. The drain is removed when the abscess cavity collapses, as confirmed on CT scan images. Presence of ascites and proximity to vital structures are contraindications to percutaneous drainage. Coagulopathy can be corrected with transfusion of fresh frozen plasma prior to drainage. The success rate of percutaneous drainage ranges from 80-87%. Consider percutaneous drainage to have failed if no improvement occurs, if the condition worsens within 72 hours of drainage, or if the abscess recurs despite adequate initial drainage. Percutaneous drainage failure can be treated by either inserting a second catheter or performing open surgical drainage. Complications of percutaneous drainage include perforation of adjacent abdominal organs, pneumothorax, hemorrhage, and leakage of the abscess cavity into the peritoneum. Immunocompromised patients with multiple diffuse microabscesses are not candidates for either percutaneous or open surgical drainage and are best treated with high-dose antibiotics. Such patients have the highest mortality rate. Surgical therapySurgical drainage used to be the criterion standard in treating liver abscesses. Currently, surgical drainage is indicated as follows:
The presence of peritoneal signs in a patient with pyogenic liver abscess mandates emergent laparotomy because free rupture of the abscess into the peritoneal cavity may have occurred. Intraoperative detailsThe 3 approaches to open drainage of pyogenic liver abscess are transpleural, extraperitoneal, and transperitoneal. Prior to antibiotics, the extraperitoneal approach was often used to avoid contamination of the peritoneal cavity. Nowadays, with the availability of broad-spectrum antibiotics, the transperitoneal approach is safe and is considered the preferred approach because it allows thorough inspection of the peritoneal cavity and permits the mobilization necessary for adequate drainage. Hepatic resection has been advocated when drainage and antibiotics are unlikely to be curative. Examples include secondary infection of a hepatic malignancy or hepatic abscesses associated with chronic granulomatous diseases of childhood. A necrotic right lobe from vascular injury during laparoscopic cholecystectomy with recurrent abscesses secondary to intrahepatic biliary strictures might require a right hepatic lobectomy. COMPLICATIONSSection 7 of 11
The complications of liver abscess result from rupture of the abscess into adjacent organs or body cavities. These include both pleuropulmonary and intra-abdominal types. Pleuropulmonary complications are the most common and have been reported in 15-20% of early series. These include pleurisy and pleural effusion, empyema, and broncho-hepatic fistula. Intra-abdominal complications are also common. These complications include subphrenic abscess and rupture into the peritoneal cavity, stomach, colon, vena cava, or kidney. A large abscess compressing the inferior vena cava and the hepatic veins can result in Budd-Chiari syndrome. Rupture into the pericardium or brain abscess from hematogenous spread is rare. OUTCOME AND PROGNOSISSection 8 of 11
Untreated, pyogenic liver abscess is associated with 100% mortality. Early series reported a mortality rate of greater than 80%. With early diagnosis, appropriate drainage, and long-term antibiotic therapy, the prognosis has improved markedly, with mortality rates in the range of 15-20%. The 4 poor prognostic factors are as follows:
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With increasing experience in the laparoscopic approach to liver lesions, laparoscopic drainage of pyogenic hepatic abscesses is now being safely performed. The laparoscopic approach eliminates access trauma and can help detect predisposing pathology. Intraoperative laparoscopic ultrasound can accurately detect the location of the abscess to allow for drainage under ultrasonographic guidance. As experience with the use of the laparoscope increases, its application in the management of hepatic abscess continues to evolve. MULTIMEDIASection 10 of 11
REFERENCESSection 11 of 11
Pyogenic Hepatic Abscesses excerpt Article Last Updated: Mar 22, 2006 | |||||||||||||||||||||||||||||||||||||||||||||||||||
