Spontaneous bacterial peritonitis
Encyclopedia
Spontaneous bacterial peritonitis (SBP) is the development of peritonitis
(infection
in the abdominal cavity
) despite the absence of an obvious source for the infection. It occurs almost exclusively in people with portal hypertension
(increased pressure over the portal vein), usually as a result of cirrhosis
of the liver
. It can also occur in patients with nephrotic syndrome
.
The diagnosis of SBP requires paracentesis
(aspiration of fluid with a needle) from the abdominal cavity. If the fluid contains bacteria
or large numbers of neutrophil granulocyte
s (a type of white blood cells), infection is confirmed and antibiotic
s are required to avoid complications. In addition to antibiotics, infusions of albumin
are usually administered.
, chills, nausea
, vomiting
, abdominal tenderness and general malaise
. Patients may complain of abdominal pain and worsening ascites
. Thirteen percent of patients have no signs or symptoms. Hepatic encephalopathy
may be the only manifestation of SBP; in the absence of a clear precipitant for the encephalopathy, all patients should undergo paracentesis
, or sampling of the ascites fluid, in order to assess for SBP.
secondary to compromised host defenses, intrahepatic shunting of colonized blood
, and defective bactericidal activity within the ascitic fluid. Contrary to earlier theories, transmucosal migration of bacteria from the gut to the ascitic fluid is no longer considered to play a major role in the etiology of SBP.
With respect to compromised host defenses
, patients with severe acute or chronic liver disease are often deficient in complement
and may also have malfunctioning of the neutrophilic and reticuloendothelial systems.
As for the significance of ascitic fluid proteins, it was demonstrated that cirrhotic patients with ascitic protein concentrations below 1 g/dL were 10 times more likely to develop SBP than individuals with higher concentrations. It is thought that the antibacterial, or opsonic, activity of ascitic fluid is closely correlated with the protein concentration. Additional studies have confirmed the validity of the ascitic fluid protein concentration as the best predictor of the first episode of SBP.
(needle drainage of the ascitic fluid) and laboratory confirmation of ascitic neutrophils > 250/mm³.
2g IV Q8-12H for at least 5 days or ceftriaxone
2g IV Q24H). They will often also receive intravenous albumin. A repeat paracentesis in 48 hours is sometimes performed to ensure control of infection. Once patients have recovered from SBP, they require regular prophylactic antibiotics (e.g. Septra DS 1 tab 5 times/week, Ciprofloxacin
750 mg PO Q1W, norfloxacin
400 mg Q24H) as long as they still have ascites
.
found that intravenous albumin on the day of admission and on hospital day 3 can reduce renal impairment.
Cirrhotic patients admitted to the hospital should receive antibiotics if:
Peritonitis
Peritonitis is an inflammation of the peritoneum, the serous membrane that lines part of the abdominal cavity and viscera. Peritonitis may be localised or generalised, and may result from infection or from a non-infectious process.-Abdominal pain and tenderness:The main manifestations of...
(infection
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
in the abdominal cavity
Abdominal cavity
The abdominal cavity is the body cavity of the human body that holds the bulk of the viscera. It is located below the thoracic cavity, and above the pelvic cavity. Its dome-shaped roof is the thoracic diaphragm , and its oblique floor is the pelvic inlet...
) despite the absence of an obvious source for the infection. It occurs almost exclusively in people with portal hypertension
Portal hypertension
In medicine, portal hypertension is hypertension in the portal vein and its tributaries.It is often defined as a portal pressure gradient of 10 mmHg or greater.-Causes:Causes can be divided into prehepatic, intrahepatic, and posthepatic...
(increased pressure over the portal vein), usually as a result of cirrhosis
Cirrhosis
Cirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue and regenerative nodules , leading to loss of liver function...
of the liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
. It can also occur in patients with nephrotic syndrome
Nephrotic syndrome
Nephrotic syndrome is a nonspecific disorder in which the kidneys are damaged, causing them to leak large amounts of protein from the blood into the urine....
.
The diagnosis of SBP requires paracentesis
Paracentesis
Paracentesis is a medical procedure involving needle drainage of fluid from a body cavity, most commonly the peritoneal cavity in the abdomen.A related procedure is thoracocentesis, which is needle drainage of the chest cavity...
(aspiration of fluid with a needle) from the abdominal cavity. If the fluid contains bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
or large numbers of neutrophil granulocyte
Neutrophil granulocyte
Neutrophil granulocytes are the most abundant type of white blood cells in mammals and form an essential part of the innate immune system. They are generally referred to as either neutrophils or polymorphonuclear neutrophils , and are subdivided into segmented neutrophils and banded neutrophils...
s (a type of white blood cells), infection is confirmed and antibiotic
Antibiotic
An antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...
s are required to avoid complications. In addition to antibiotics, infusions of albumin
Albumin
Albumin refers generally to any protein that is water soluble, which is moderately soluble in concentrated salt solutions, and experiences heat denaturation. They are commonly found in blood plasma, and are unique to other blood proteins in that they are not glycosylated...
are usually administered.
Symptoms
Symptoms include feversFevers
Fevers are a five-piece band formed in 2010 in Ottawa, Ontario. The band consists of Colin MacDougall , Jim Hopkins , Martin Charbonneau , Sarah Bradley and Mike Stauffer . Theirs is a fresh take on a classic genre, combining indie rock and electronic music...
, chills, nausea
Nausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...
, vomiting
Vomiting
Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...
, abdominal tenderness and general malaise
Malaise
Malaise is a feeling of general discomfort or uneasiness, of being "out of sorts", often the first indication of an infection or other disease. Malaise is often defined in medicinal research as a "general feeling of being unwell"...
. Patients may complain of abdominal pain and worsening ascites
Ascites
Ascites is a gastroenterological term for an accumulation of fluid in the peritoneal cavity.The medical condition is also known as peritoneal cavity fluid, peritoneal fluid excess, hydroperitoneum or more archaically as abdominal dropsy. Although most commonly due to cirrhosis and severe liver...
. Thirteen percent of patients have no signs or symptoms. Hepatic encephalopathy
Hepatic encephalopathy
Hepatic encephalopathy is the occurrence of confusion, altered level of consciousness and coma as a result of liver failure. In the advanced stages it is called hepatic coma or coma hepaticum...
may be the only manifestation of SBP; in the absence of a clear precipitant for the encephalopathy, all patients should undergo paracentesis
Paracentesis
Paracentesis is a medical procedure involving needle drainage of fluid from a body cavity, most commonly the peritoneal cavity in the abdomen.A related procedure is thoracocentesis, which is needle drainage of the chest cavity...
, or sampling of the ascites fluid, in order to assess for SBP.
Pathogenesis
SBP is thought to result from a combination of factors inherent in cirrhosis and ascites, such as prolonged bacteremiaBacteremia
Bacteremia is the presence of bacteria in the blood. The blood is normally a sterile environment, so the detection of bacteria in the blood is always abnormal....
secondary to compromised host defenses, intrahepatic shunting of colonized blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
, and defective bactericidal activity within the ascitic fluid. Contrary to earlier theories, transmucosal migration of bacteria from the gut to the ascitic fluid is no longer considered to play a major role in the etiology of SBP.
With respect to compromised host defenses
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
, patients with severe acute or chronic liver disease are often deficient in complement
Complement system
The complement system helps or “complements” the ability of antibodies and phagocytic cells to clear pathogens from an organism. It is part of the immune system called the innate immune system that is not adaptable and does not change over the course of an individual's lifetime...
and may also have malfunctioning of the neutrophilic and reticuloendothelial systems.
As for the significance of ascitic fluid proteins, it was demonstrated that cirrhotic patients with ascitic protein concentrations below 1 g/dL were 10 times more likely to develop SBP than individuals with higher concentrations. It is thought that the antibacterial, or opsonic, activity of ascitic fluid is closely correlated with the protein concentration. Additional studies have confirmed the validity of the ascitic fluid protein concentration as the best predictor of the first episode of SBP.
Diagnosis
Diagnosis necessitates paracentesisParacentesis
Paracentesis is a medical procedure involving needle drainage of fluid from a body cavity, most commonly the peritoneal cavity in the abdomen.A related procedure is thoracocentesis, which is needle drainage of the chest cavity...
(needle drainage of the ascitic fluid) and laboratory confirmation of ascitic neutrophils > 250/mm³.
Antibiotics
After confirmation of SBP, patients need hospital admission for intravenous antibiotics (most often cefotaximeCefotaxime
Cefotaxime is a third-generation cephalosporin antibiotic. Like other third-generation cephalosporins, it has broad spectrum activity against Gram positive and Gram negative bacteria...
2g IV Q8-12H for at least 5 days or ceftriaxone
Ceftriaxone
Ceftriaxone is a third-generation cephalosporin antibiotic. Like other third-generation cephalosporins, it has broad spectrum activity against Gram-positive and Gram-negative bacteria. In most cases, it is considered to be equivalent to cefotaxime in terms of safety and efficacy...
2g IV Q24H). They will often also receive intravenous albumin. A repeat paracentesis in 48 hours is sometimes performed to ensure control of infection. Once patients have recovered from SBP, they require regular prophylactic antibiotics (e.g. Septra DS 1 tab 5 times/week, Ciprofloxacin
Ciprofloxacin
Ciprofloxacin is a synthetic chemotherapeutic antibiotic of the fluoroquinolone drug class.It is a second-generation fluoroquinolone antibacterial. It kills bacteria by interfering with the enzymes that cause DNA to rewind after being copied, which stops synthesis of DNA and of...
750 mg PO Q1W, norfloxacin
Norfloxacin
Norfloxacin is a synthetic chemotherapeutic antibacterial agent occasionally used to treat common as well as complicated urinary tract infections. It is sold under various brand names with the most common being Noroxin. In form of ophthalmic solutions it is known as Chibroxin...
400 mg Q24H) as long as they still have ascites
Ascites
Ascites is a gastroenterological term for an accumulation of fluid in the peritoneal cavity.The medical condition is also known as peritoneal cavity fluid, peritoneal fluid excess, hydroperitoneum or more archaically as abdominal dropsy. Although most commonly due to cirrhosis and severe liver...
.
Intravenous albumin
A randomized controlled trialRandomized controlled trial
A randomized controlled trial is a type of scientific experiment - a form of clinical trial - most commonly used in testing the safety and efficacy or effectiveness of healthcare services or health technologies A randomized controlled trial (RCT) is a type of scientific experiment - a form of...
found that intravenous albumin on the day of admission and on hospital day 3 can reduce renal impairment.
Prevention/screening
All cirrhotic patients might benefit from antibiotics if:- Ascitic fluid protein <1.0 g/dL. Patients with fluid protein <15 g/L and either Child-Pugh score of at least 9 or impaired renal function may also benefit.
- Previous SBP
Cirrhotic patients admitted to the hospital should receive antibiotics if:
- They have bleeding esophageal varicesEsophageal varicesIn medicine , esophageal varices are extremely dilated sub-mucosal veins in the lower esophagus...