Pancreatic abscess
Encyclopedia
Pancreatic abscess is a late complication of acute necrotizing pancreatitis
, occurring more than 4 weeks after the initial attack. A pancreatic abscess is a collection of pus
resulting from tissue necrosis
, liquefaction
, and infection
. It is estimated that approximately 3% of the patients suffering from acute pancreatitis will develop an abscess.
According to the Balthazar and Ranson's radiographic staging criteria, patients with a normal pancreas, an enlargement that is focal or diffuse, mild peripancreatic inflammations or a single collection of fluid (pseudocyst) have less than 2% chances of developing an abscess. However, the probability of developing an abscess increases to nearly 60% in patients with more than two pseudocysts and gas
within the pancreas.
, chills and fever
or the inability to eat. Whereas some patients present an abdominal mass, others do not. Nausea and vomiting may also occur.
collections or penetrating peptic ulcer
s. Other causes include gall stones or alcohol
consumption and, in rare cases, drugs
and blunt trauma
.
is required as a first step in diagnosing abscesses. On the other hand, a white blood cell count is the only laboratory test that may indicate the presence of an abscess.
Some of the imaging tests are more commonly used to diagnose this condition. Abdominal CT scans, MRIs and ultrasounds are helpful in providing clear images of the inside of the abdomen
and successfully used in the diagnosing process. These tests may reveal the presence of infected necrosis which has not yet developed into an abscess and as a result, doctors usually order repeated imaging tests in patients with acute pancreatitis whose abdominal pain worsens and who develop signs of abdominal obstruction. Also, it is recommended that patients who have a prolonged clinical response are tested repeatedly as a prevention method to avoid the development of an abscess that may rupture.
, Staphylococcus aureus
, Pseudomonas aeruginosa
, Proteus mirabilis
, and Streptococcus
species. Medical therapy is usually given to people whose general health status does not allow surgery. On the other hand, antibiotics are not recommended in patients with pancreatitis, unless the presence of an infected abscess has been proved.
Although there have been reported cases of patients who were given medical treatment and survived, primary drainage
of the abscess is the main treatment use to cure this condition. Drainage usually involves a surgical procedure. It has been shown that CT-guided drainage brought inferior results than open drainage. Hence, open surgical procedure is preferred to successfully remove the abscess. However, CT-guided drainage is the option treatment for patients who may not tolerate an open procedure. Endoscopic treatment is at the same time a treatment option that increased in popularity over the last years.
. Also, multiple abscesses may occur. Other complications may include fistula
formation and recurrent pancreatitis.
Pancreatitis
Pancreatitis is inflammation of the pancreas. It occurs when pancreatic enzymes that digest food are activated in the pancreas instead of the small intestine. It may be acute – beginning suddenly and lasting a few days, or chronic – occurring over many years...
, occurring more than 4 weeks after the initial attack. A pancreatic abscess is a collection of pus
Pus
Pus is a viscous exudate, typically whitish-yellow, yellow, or yellow-brown, formed at the site of inflammatory during infection. An accumulation of pus in an enclosed tissue space is known as an abscess, whereas a visible collection of pus within or beneath the epidermis is known as a pustule or...
resulting from tissue necrosis
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...
, liquefaction
Liquefaction
Liquefaction may refer to:* Liquefaction, the general process of becoming liquid* Soil liquefaction, the process by which sediments become suspended* Liquefaction of gases in physics, chemistry, and thermal engineering* Liquefactive necrosis in pathology...
, and 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...
. It is estimated that approximately 3% of the patients suffering from acute pancreatitis will develop an abscess.
According to the Balthazar and Ranson's radiographic staging criteria, patients with a normal pancreas, an enlargement that is focal or diffuse, mild peripancreatic inflammations or a single collection of fluid (pseudocyst) have less than 2% chances of developing an abscess. However, the probability of developing an abscess increases to nearly 60% in patients with more than two pseudocysts and gas
Gas
Gas is one of the three classical states of matter . Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point , boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons...
within the pancreas.
Signs and symptoms
Patients with pancreatic abscesses may experience abdominal painAbdominal pain
Abdominal pain can be one of the symptoms associated with transient disorders or serious disease. Making a definitive diagnosis of the cause of abdominal pain can be difficult, because many diseases can result in this symptom. Abdominal pain is a common problem...
, chills and fever
Fever
Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
or the inability to eat. Whereas some patients present an abdominal mass, others do not. Nausea and vomiting may also occur.
Causes
Pancreatic abscesses usually develop in patients with pancreatic pseudocysts that become infected. They may also form as a result of fibrous wall formation around fluidFluid
In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids....
collections or penetrating peptic ulcer
Peptic ulcer
A peptic ulcer, also known as PUD or peptic ulcer disease, is the most common ulcer of an area of the gastrointestinal tract that is usually acidic and thus extremely painful. It is defined as mucosal erosions equal to or greater than 0.5 cm...
s. Other causes include gall stones or alcohol
Alcohol
In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....
consumption and, in rare cases, drugs
DRUGS
Destroy Rebuild Until God Shows are an American post-hardcore band formed in 2010. They released their debut self-titled album on February 22, 2011.- Formation :...
and blunt trauma
Blunt trauma
In medical terminology, blunt trauma, blunt injury, non-penetrating trauma or blunt force trauma refers to a type of physical trauma caused to a body part, either by impact, injury or physical attack; the latter usually being referred to as blunt force trauma...
.
Diagnosis
Most patients who develop pancreatic abscesses have had pancreatitis, so a complete medical historyMedical history
The medical history or anamnesis of a patient is information gained by a physician by asking specific questions, either of the patient or of other people who know the person and can give suitable information , with the aim of obtaining information useful in formulating a diagnosis and providing...
is required as a first step in diagnosing abscesses. On the other hand, a white blood cell count is the only laboratory test that may indicate the presence of an abscess.
Some of the imaging tests are more commonly used to diagnose this condition. Abdominal CT scans, MRIs and ultrasounds are helpful in providing clear images of the inside of the abdomen
Abdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
and successfully used in the diagnosing process. These tests may reveal the presence of infected necrosis which has not yet developed into an abscess and as a result, doctors usually order repeated imaging tests in patients with acute pancreatitis whose abdominal pain worsens and who develop signs of abdominal obstruction. Also, it is recommended that patients who have a prolonged clinical response are tested repeatedly as a prevention method to avoid the development of an abscess that may rupture.
Treatment
Antibiotics are commonly used as a curing method for pancreatic abscesses although their role remains controversial. Prophylactic antibiotics are normally chosen based on the type of flora and the degree of antibiotic penetration into the abscess. Pancreatic abscesses are more likely to host enteric organisms and pathogens such as E. coli, Klebsiella pneumonia, Enterococcus faecalisEnterococcus faecalis
Enterococcus faecalis – formerly classified as part of the Group D Streptococcus system – is a Gram-positive, commensal bacterium inhabiting the gastrointestinal tracts of humans and other mammals. It is among the main constituents of some probiotic food supplements. Like other species in the genus...
, Staphylococcus aureus
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. It is frequently found as part of the normal skin flora on the skin and nasal passages. It is estimated that 20% of the human population are long-term carriers of S. aureus. S. aureus is the most common species of...
, Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
, Proteus mirabilis
Proteus mirabilis
Proteus mirabilis is a Gram-negative, facultatively anaerobic, rod shaped bacterium. It shows swarming motility, and urease activity. P. mirabilis causes 90% of all Proteus infections in humans.-Diagnosis:...
, and Streptococcus
Streptococcus
Streptococcus is a genus of spherical Gram-positive bacteria belonging to the phylum Firmicutes and the lactic acid bacteria group. Cellular division occurs along a single axis in these bacteria, and thus they grow in chains or pairs, hence the name — from Greek στρεπτος streptos, meaning...
species. Medical therapy is usually given to people whose general health status does not allow surgery. On the other hand, antibiotics are not recommended in patients with pancreatitis, unless the presence of an infected abscess has been proved.
Although there have been reported cases of patients who were given medical treatment and survived, primary drainage
Drainage
Drainage is the natural or artificial removal of surface and sub-surface water from an area. Many agricultural soils need drainage to improve production or to manage water supplies.-Early history:...
of the abscess is the main treatment use to cure this condition. Drainage usually involves a surgical procedure. It has been shown that CT-guided drainage brought inferior results than open drainage. Hence, open surgical procedure is preferred to successfully remove the abscess. However, CT-guided drainage is the option treatment for patients who may not tolerate an open procedure. Endoscopic treatment is at the same time a treatment option that increased in popularity over the last years.
Prevention
In some cases, abscesses may be prevented by draining an existing pseudocyst which is likely to become inflamed. However, in most cases the developing of abscesses cannot be prevented.Complications
An unremoved infected abscess may lead to sepsisSepsis
Sepsis is a potentially deadly medical condition that is characterized by a whole-body inflammatory state and the presence of a known or suspected infection. The body may develop this inflammatory response by the immune system to microbes in the blood, urine, lungs, skin, or other tissues...
. Also, multiple abscesses may occur. Other complications may include fistula
Fistula
In medicine, a fistula is an abnormal connection or passageway between two epithelium-lined organs or vessels that normally do not connect. It is generally a disease condition, but a fistula may be surgically created for therapeutic reasons.-Locations:Fistulas can develop in various parts of the...
formation and recurrent pancreatitis.