Peliosis hepatis
Encyclopedia
Peliosis Hepatis is an uncommon vascular
condition characterised by randomly distributed multiple blood-filled cavities throughout the liver
. The size of the cavities usually ranges between a few millimetres to 3 cm in diameter. In the past it was a mere histological curiosity occasionally found at autopsies but has been increasingly recognised with wide ranging conditions from AIDS
to the use of anabolic steroid
s. It also occasionally affects spleen
, lymph node
s, lung
s, kidney
s, adrenal gland
s, bone marrow
and other parts of gastrointestinal tract
.
Peliosis hepatis is often erroneously written "peliosis hepatitis", despite its not being one of the hepatitides
. The correct term arises from the Greek
pelios, i.e. discoloured by extravasated blood, livid, and the Latinized genitive case
(hepatis) of the Greek
hepar, liver.
of peliosis hepatis is unknown. There are several hypotheses, such as, it arises from sinusoidal
epithelial damage, increased sinusoidal pressure due to obstruction in blood outflow from the liver, or hepatocellular necrosis
.
Two morphologic
patterns of hepatic peliosis were described by Yanoff and Rawson. In the phlebectatic type, the blood-filled spaces are lined with endothelium
and are associated with aneurysm
al dilatation of the central vein; in the parenchymal type, the spaces have no endothelial lining and they usually are associated with haemorrhagic parenchyma
l necrosis. Some consider both patterns to be one process, initiated by focal necrosis
of liver parenchyma, observed in parenchymal type, progressing into formation of fibrous wall and endothelial lining around haemorrhage of phebectatic type. Fibrosis
, cirrhosis
, regenerative nodules, and tumours may also be seen.
, hepatomegaly
, liver failure
and haemoperitoneum.
, bacillary peliosis responds to antibiotics. In rare circumstances partial resection of liver or transplant
may be required.
Blood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...
condition characterised by randomly distributed multiple blood-filled cavities throughout 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...
. The size of the cavities usually ranges between a few millimetres to 3 cm in diameter. In the past it was a mere histological curiosity occasionally found at autopsies but has been increasingly recognised with wide ranging conditions from AIDS
AIDS
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome is a disease of the human immune system caused by the human immunodeficiency virus...
to the use of anabolic steroid
Anabolic steroid
Anabolic steroids, technically known as anabolic-androgen steroids or colloquially simply as "steroids", are drugs that mimic the effects of testosterone and dihydrotestosterone in the body. They increase protein synthesis within cells, which results in the buildup of cellular tissue ,...
s. It also occasionally affects spleen
Spleen
The spleen is an organ found in virtually all vertebrate animals with important roles in regard to red blood cells and the immune system. In humans, it is located in the left upper quadrant of the abdomen. It removes old red blood cells and holds a reserve of blood in case of hemorrhagic shock...
, lymph node
Lymph node
A lymph node is a small ball or an oval-shaped organ of the immune system, distributed widely throughout the body including the armpit and stomach/gut and linked by lymphatic vessels. Lymph nodes are garrisons of B, T, and other immune cells. Lymph nodes are found all through the body, and act as...
s, lung
Lung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
s, kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
s, adrenal gland
Adrenal gland
In mammals, the adrenal glands are endocrine glands that sit atop the kidneys; in humans, the right suprarenal gland is triangular shaped, while the left suprarenal gland is semilunar shaped...
s, bone marrow
Bone marrow
Bone marrow is the flexible tissue found in the interior of bones. In humans, bone marrow in large bones produces new blood cells. On average, bone marrow constitutes 4% of the total body mass of humans; in adults weighing 65 kg , bone marrow accounts for approximately 2.6 kg...
and other parts of gastrointestinal tract
Gastrointestinal tract
The human gastrointestinal tract refers to the stomach and intestine, and sometimes to all the structures from the mouth to the anus. ....
.
Peliosis hepatis is often erroneously written "peliosis hepatitis", despite its not being one of the hepatitides
Hepatitis
Hepatitis is a medical condition defined by the inflammation of the liver and characterized by the presence of inflammatory cells in the tissue of the organ. The name is from the Greek hepar , the root being hepat- , meaning liver, and suffix -itis, meaning "inflammation"...
. The correct term arises from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
pelios, i.e. discoloured by extravasated blood, livid, and the Latinized genitive case
Genitive case
In grammar, genitive is the grammatical case that marks a noun as modifying another noun...
(hepatis) of the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
hepar, liver.
Pathophysiology
The pathogenesisPathogenesis
The pathogenesis of a disease is the mechanism by which the disease is caused. The term can also be used to describe the origin and development of the disease and whether it is acute, chronic or recurrent...
of peliosis hepatis is unknown. There are several hypotheses, such as, it arises from sinusoidal
Sinusoid (blood vessel)
A sinusoid is a small blood vessel similar to a capillary but with a fenestrated endothelium. Fenestrations are pores in the endothelial cells that greatly increase their permeability. In addition, permeability is increased by large inter-cellular clefts and fewer tight junctions...
epithelial damage, increased sinusoidal pressure due to obstruction in blood outflow from the liver, or hepatocellular 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...
.
Two morphologic
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
patterns of hepatic peliosis were described by Yanoff and Rawson. In the phlebectatic type, the blood-filled spaces are lined with endothelium
Endothelium
The endothelium is the thin layer of cells that lines the interior surface of blood vessels, forming an interface between circulating blood in the lumen and the rest of the vessel wall. These cells are called endothelial cells. Endothelial cells line the entire circulatory system, from the heart...
and are associated with aneurysm
Aneurysm
An aneurysm or aneurism is a localized, blood-filled balloon-like bulge in the wall of a blood vessel. Aneurysms can commonly occur in arteries at the base of the brain and an aortic aneurysm occurs in the main artery carrying blood from the left ventricle of the heart...
al dilatation of the central vein; in the parenchymal type, the spaces have no endothelial lining and they usually are associated with haemorrhagic parenchyma
Parenchyma
Parenchyma is a term used to describe a bulk of a substance. It is used in different ways in animals and in plants.The term is New Latin, f. Greek παρέγχυμα - parenkhuma, "visceral flesh", f. παρεγχεῖν - parenkhein, "to pour in" f. para-, "beside" + en-, "in" + khein, "to pour"...
l necrosis. Some consider both patterns to be one process, initiated by focal 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...
of liver parenchyma, observed in parenchymal type, progressing into formation of fibrous wall and endothelial lining around haemorrhage of phebectatic type. Fibrosis
Fibrosis
Fibrosis is the formation of excess fibrous connective tissue in an organ or tissue in a reparative or reactive process. This is as opposed to formation of fibrous tissue as a normal constituent of an organ or tissue...
, 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...
, regenerative nodules, and tumours may also be seen.
Disease associations
- Infections: HIVHIVHuman immunodeficiency virus is a lentivirus that causes acquired immunodeficiency syndrome , a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive...
, Bacillary peliosisBacillary peliosisBacillary peliosis is a form of peliosis hepatis that has been associated with bacteria in the genus Bartonella....
(caused by genus BartonellaBartonellaBartonella is a genus of Gram-negative bacteria. Facultative intracellular parasites, Bartonella species can infect healthy people but are considered especially important as opportunistic pathogens. Bartonella are transmitted by insect vectors such as ticks, fleas, sand flies and mosquitoes...
, bacteria responsible for cat-scratch disease which are identified histologically adjacent to the peliotic lesions), Staphylococcus aureusStaphylococcus aureusStaphylococcus 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... - Chronic conditions: End stage renal failureRenal failureRenal failure or kidney failure describes a medical condition in which the kidneys fail to adequately filter toxins and waste products from the blood...
, KwashiorkorKwashiorkorKwashiorkor is an acute form of childhood protein-energy malnutrition characterized by edema, irritability, anorexia, ulcerating dermatoses, and an enlarged liver with fatty infiltrates. The presence of edema caused by poor nutrition defines kwashiorkor...
, tuberculosisTuberculosisTuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
and other chronic infections. - Malignancy: Monoclonal gammopathiesMonoclonal gammopathyMonoclonal gammopathy is a synonym for paraproteinemia.- External links :*...
(multiple myelomaMultiple myelomaMultiple myeloma , also known as plasma cell myeloma or Kahler's disease , is a cancer of plasma cells, a type of white blood cell normally responsible for the production of antibodies...
and Waldenstrom macroglobulinemiaWaldenström macroglobulinemiaWaldenström's macroglobulinemia is cancer involving a subtype of white blood cells called lymphocytes. The main attributing antibody is Immunoglobulin M . WM is an "indolent lymphoma,"...
), Hodgkin disease, malignant histiocytosisMalignant histiocytosisMalignant histiocytosis is a rare hereditary disease found in the Bernese Mountain Dog and humans, characterized by histiocytic infiltration of the lungs and lymph nodes. The liver, spleen, and central nervous system can also be affected. Histiocytes are a component of the immune system that...
, seminoma, hepatocellular adenomaHepatocellular adenomaHepatocellular adenoma, also hepatic adenoma, or rarely hepadenoma, is an uncommon benign liver tumor which is associated with the use of hormonal contraception with a high estrogen content...
and hepatocarcinoma, - Renal transplants: It can be found in up to 20% patients, can be related to azathioprine or cyclosporine use and may be associated with increased risk of transplant rejectionTransplant rejectionTransplant rejection occurs when transplanted tissue is rejected by the recipient's immune system, which destroys the transplanted tissue. Transplant rejection can be lessened by determining the molecular similitude between donor and recipient and by use of immunosuppressant drugs after...
. - Drugs and toxins: Corticosteroids, androgens, azathioprineAzathioprineAzathioprine is a purine analogue immunosuppressive drug. It is used to prevent organ rejection following organ transplantation and to treat a vast array of autoimmune diseases, including rheumatoid arthritis, pemphigus, inflammatory bowel disease , multiple sclerosis, autoimmune hepatitis, atopic...
, tamoxifenTamoxifenTamoxifen is an antagonist of the estrogen receptor in breast tissue via its active metabolite, hydroxytamoxifen. In other tissues such as the endometrium, it behaves as an agonist, hence tamoxifen may be characterized as a mixed agonist/antagonist...
Clinical features
The condition is typically asymptomatic and is discovered following evaluation of abnormal liver function test. However, when severe it can manifest as jaundiceJaundice
Jaundice is a yellowish pigmentation of the skin, the conjunctival membranes over the sclerae , and other mucous membranes caused by hyperbilirubinemia . This hyperbilirubinemia subsequently causes increased levels of bilirubin in the extracellular fluid...
, hepatomegaly
Hepatomegaly
Hepatomegaly is the condition of having an enlarged liver. It is a nonspecific medical sign having many causes, which can broadly be broken down into infection, direct toxicity, hepatic tumours, or metabolic disorder. Often, hepatomegaly will present as an abdominal mass...
, liver failure
Liver failure
Acute liver failure is the appearance of severe complications rapidly after the first signs of liver disease , and indicates that the liver has sustained severe damage . The complications are hepatic encephalopathy and impaired protein synthesis...
and haemoperitoneum.
Treatment
Usually directed towards management of underlying cause. Withdrawal of azathioprine leads to remission in renal transplantKidney transplantation
Kidney transplantation or renal transplantation is the organ transplant of a kidney into a patient with end-stage renal disease. Kidney transplantation is typically classified as deceased-donor or living-donor transplantation depending on the source of the donor organ...
, bacillary peliosis responds to antibiotics. In rare circumstances partial resection of liver or transplant
Liver transplantation
Liver transplantation or hepatic transplantation is the replacement of a diseased liver with a healthy liver allograft. The most commonly used technique is orthotopic transplantation, in which the native liver is removed and replaced by the donor organ in the same anatomic location as the original...
may be required.
Other cystic conditions of liver
- Polycystic liver diseasePolycystic liver diseasePolycystic liver disease usually describes the presence of multiple cysts scattered throughout normal liver tissue, in association with polycystic kidney disease.-Pathophysiology:Associations with PRKCSH and SEC63 have been described....
- Solitary congenital cysts
- Congenital hepatic fibrosisCongenital hepatic fibrosisCongenital hepatic fibrosis is an inherited fibrocystic liver disease associated with proliferation of interlobular bile ducts within the portal areas and fibrosis that do not alter hepatic lobular architecture. The fibrosis would affect resistance in portal veins leading to portal...
- Hydatid cystEchinococcosisEchinococcosis, which is often referred to as hydatid disease or echinococcal disease, is a parasitic disease that affects both humans and other mammals, such as sheep, dogs, rodents and horses. There are three different forms of echinococcosis found in humans, each of which is caused by the larval...
- Von Meyenburg complexes
- Caroli diseaseCaroli diseaseCaroli disease is a rare inherited disorder characterized by dilatation of the intrahepatic bile ducts. There are two types of Caroli disease, the most common being the simple, or isolated case where the bile ducts are widened by ectasia. The second, more complex, cause is commonly known as Caroli...
(type V choledochal cyst) - Type IV choledochal cystsCholedochal cystsCholedochal cysts are congenital conditions involving cystic dilatation of bile ducts. They are uncommon in western countries but not as rare in East Asian nations like Japan and China.-Signs and symtoms:...