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Most (>95%) infants with biliary atresia will undergo an operation designed to retain and salvage the native liver, restore bile flow and reduce the level of jaundice. This is known as the Kasai procedure (after Morio Kasai, the Japanese surgeon who first developed the technique) or hepatoportoenterostomy. Although the procedure is not thought of as curative, it may relieve jaundice, and stop liver fibrosis allowing normal growth and development. Published series from Japan, North America and the UK show that bilirubin levels will fall to normal values in about 50-55% of infants allowing 40-50% to retain their own liver to reach the age of 5 and 10 years (and beyond). Liver transplantation is an option for those children whose liver function and symptoms fail to respond to a Kasai operation.
Recent large-scale studies by Davenport et al. ("Annals of Surgery", 2008) show that the age of the patient is not an absolute clinical factor affecting prognosis. The influence of age differs according to the disease etiology—i.e., whether biliary atresia is isolated, cystic (CBA), or accompanied by splenic malformation (BASM).
It is widely accepted that corticosteroid treatment after a Kasai operation, with or without choleretics and antibiotics, has a beneficial effect on postoperative bile flow and can clear jaundice, but the dosing and duration of the ideal steroid protocol are controversial. Furthermore, it has been observed in many retrospective longitudinal studies that corticosteroid treatment does not prolong survival of the native liver or transplant-free survival. Davenport et al. also showed ("Hepatology" 2007) that short-term, low-dose steroid therapy following a Kasai operation had no effect on the mid- or long-term prognosis of biliary atresia patients.
Biliary atresia seems to affect females slightly more often than males, and Asians and African Americans more often than Caucasians. It is common for only one child in a pair of twins or within the same family to have the condition. There seems to be no link to medications or immunizations given immediately before or during pregnancy. Diabetes during pregnancy particularly during the first trimester seems to predispose to a number of distinct congenital abnormalities in the infant such as sacral agenesis and the syndromic form of biliary atresia.
Initial treatment is supportive, with the use of agents to treat cholestasis and pruritus, including the following:
- Ursodeoxycholic acid
- Cholestyramine
- Rifampin
- Naloxone, in refractory cases
The partial external biliary diversion (PEBD) procedure is a surgical approach that diverts bile from the gallbladder externally into an ileostomy bag.
Patients should be supplemented with fat-soluble vitamins, and occasionally medium-chain triglycerides in order to improve growth.
When liver synthetic dysfunction is significant, patients should be listed for transplantation. Family members should be tested for PFIC mutations, in order to determine risk of transmission.
No treatment is available for most of these disorders. Mannose supplementation relieves the symptoms in PMI-CDG (CDG-Ib) for the most part, even though the hepatic fibrosis may persist. Fucose supplementation has had a partial effect on some SLC35C1-CDG (CDG-IIc or LAD-II) patients.
The disease is typically progressive, leading to fulminant liver failure and death in childhood, in the absence of liver transplantation. Hepatocellular carcinoma may develop in PFIC-2 at a very early age; even toddlers have been affected.
Prognosis is good, and treatment of this syndrome is usually unnecessary. Most patients are asymptomatic and have normal lifespans. Some neonates present with cholestasis. Hormonal contraceptives and pregnancy may lead to overt jaundice and icterus (yellowing of the eyes and skin).
Early treatment is possible once the disease is detected. Once the classical symptoms appear, the best way to eliminate the dangers of Alagille syndrome is a full liver transplant. Most of the short-term treatments available are aimed at improving the functioning of the heart and reducing the effects of impaired liver, kidney, and spleen function.
Several medications are used to improve bile flow, including ursodiol (Actigall).These medications differ in their rates of success.
Certain drugs may be used to reduce itching (pruritus): hydroxyzine (Atarax), cholestyramine, rifampicin, phenobarbital, and naltrexone. Similar to the medications which improve bile flow, the anti-itching drugs vary in their success rate.
Many patients with Alagille syndrome will also benefit from a high dose of a multivitamin such as ADEK (continuing high levels of vitamins A, D, E, and K), as the reduced bile flow makes it difficult to absorb and utilize these vitamins.
While there is no cure for JBS, treatment and management of specific symptoms and features of the disorder are applied and can often be successful. Variability in the severity of JBS on a case-by-case basis determines the requirements and effectiveness of any treatment selected.
Pancreatic insufficiency and malabsorption can be managed with pancreatic enzyme replacement therapy, such as pancrelipase supplementation and other related methods.
Craniofacial and skeletal deformities may require surgical correction, using techniques including bone grafts and osteotomy procedures. Sensorineural hearing loss can be managed with the use of hearing aids and educational services designated for the hearing impaired.
Special education, specialized counseling methods and occupational therapy designed for those with mental retardation have proven to be effective, for both the patient and their families. This, too, is carefully considered for JBS patients.
A review from 2000 stated that life expectancy was reduced because of a tendency to develop cancer relatively early as well as deaths due to infections related to immunodeficiency.
Bile acid sequestrants are the main agents used to treat bile acid malabsorption. Cholestyramine and colestipol, both in powder form, have been used for many years. Unfortunately many patients find them difficult to tolerate; although the diarrhea may improve, other symptoms such as pain and bloating may worsen. Colesevelam is a tablet and some patients tolerate this more easily. A proof of concept study of the farnesoid X receptor agonist obeticholic acid has shown clinical and biochemical benefit.
As of March 15, 2016, Novartis Pharmaceuticals is conducting a phase II clinical study involving a farnesoid X receptor agonist named LJN452.
One 10-year-old girl with Crigler–Najjar syndrome type I was successfully treated by liver cell transplantation.
The homozygous Gunn rat, which lacks the enzyme uridine diphosphate glucuronyltransferase (UDPGT), is an animal model for the study of Crigler–Najjar syndrome. Since only one enzyme is working improperly, gene therapy for Crigler-Najjar is a theoretical option which is being investigated.
The intrahepatic shunts found in large dog breeds are passed on in a simple autosomal recessive way, while the extrahepatic shunts of the small breeds are inherited on a polygenic basis.
Simple cholecystectomy is suitable for type I patients. For types II–IV, subtotal cholecystectomy can be performed to avoid damage to the main bile ducts. Cholecystectomy and bilioenteric anastomosis may be required. Roux-en-Y hepaticojejunostomy has shown good outcome in some studies.
Dubin–Johnson syndrome (DJS) is a rare, autosomal recessive, benign disorder that causes an isolated increase of conjugated bilirubin in the serum. Classically, the condition causes a black liver due to the deposition of a pigment similar to melanin. This condition is associated with a defect in the ability of hepatocytes to secrete conjugated bilirubin into the bile, and is similar to Rotor syndrome. It is usually asymptomatic, but may be diagnosed in early infancy based on laboratory tests. No treatment is usually needed.
Administration of cytidine monophosphate and uridine monophosphate reduces urinary orotic acid and ameliorates the anemia.
Administration of uridine, which is converted to UMP, will bypass the metabolic block and provide the body with a source of pyrimidine.
Uridine triacetate is a drug approved by FDA to be used in the treatment of hereditary orotic aciduria.
There is no treatment for NBS, however in those with agammaglobulinemia, intravenous immunoglobulin may be started. Prophylactic antibiotics are considered to prevent urinary tract infections as those with NBS often have congenital kidney malformations. In the treat of malignancies radiation, alkylating antineoplastic agents, and epipodophyllotoxins are not used, and methotrexate can be used with caution and, the dose should be limited. Bone marrow transplants and hematopoietic stem cells transplants are also considered in the treatment of NBS. The supplementation of Vitamin E is also recommended. A ventriculoperitoneal shunt can be placed in patients with hydrocephaly, and surgical intervention of congenital deformities is also attempted.
Mortality is indirect and caused by complications. After cholangitis occurs, patients typically die within 5–10 years.
At present, no specific enzyme deficiency nor genetic mutation has been implicated as the cause of hypertryptophanemia. Several known factors regarding tryptophan metabolism and kynurenines, however, may explain the presence of behavioral abnormalities seen with the disorder.
Tryptophan is an essential amino acid, and is required for protein synthesis. Aside from this crucial role, the remainder of tryptophan is primarily metabolized along the kynurenine pathway in most tissues, including those of the brain and central nervous system.
As the main defect behind hypertryptophanemia is suspected to alter and disrupt the metabolic pathway from tryptophan to kynurenine, a possible correlation between hypertryptophanemia and the known effects of kynurenines on neuronal function, physiology and behavior may be of interest.
One of these kynurenines, aptly named kynurenic acid, serves as a neuroprotectant through its function as an antagonist at both nicotinic and glutamate receptors (responsive to the neurotransmitters nicotine and glutamate, respectively). This action is in opposition to the agonist quinolinic acid, another kynurenine, noted for its potential as a neurotoxin. Quinolinic acid activity has been associated with neurodegenerative disorders such as Huntington's disease, the neuroprective abilities of kynurenic acid forming a counterbalance against this process, and the related excitotoxicity and similar damaging effects on neurons.
Indoleic acid excretion is another indicator of hypertryptophanemia. Indirectly related to kynurenine metabolism, indole modifies neural function and human behavior by interacting with voltage-dependent sodium channels (integral membrane proteins that form ion channels, allowing vital synaptic action potentials).
Caroli disease is typically found in Asia, and diagnosed in persons under the age of 22. Cases have also been found in infants and adults. As medical imaging technology improves, diagnostic age decreases.
Some individuals may benefit from diet modification, such as a reduced fat diet, following cholecystectomy. The liver produces bile and the gallbladder acts as reservoir. From the gallbladder, bile enters the intestine in individual portions. In the absence of gallbladder, bile enters the intestine constantly, but in small quantities. Thus, it may be insufficient for digestion of fatty foods. Postcholecystectomy syndrome treatment depends on the identified violations that led to it. Typically, the patient is recommended dietary restriction table with fatty foods, enzyme preparations, antispasmodics, sometimes cholagogue.
If the pain is caused by biliary microlithiasis, oral ursodeoxycholic acid can alleviate the condition.
A trial of bile acid sequestrant therapy is recommended for bile acid diarrhoea.
Extrahepatic cholestasis can usually be treated by surgery.
Pruritis in cholestatic jaundice is treated by Antihistamines, Ursodeoxycholic Acid, Phenobarbital
Johanson–Blizzard syndrome (JBS) is a rare, sometimes fatal autosomal recessive multisystem congenital disorder featuring abnormal development of the pancreas, nose and scalp, with mental retardation, hearing loss and growth failure. It is sometimes described as a form of ectodermal dysplasia.
The disorder is especially noted for causing profound developmental errors and exocrine dysfunction of the pancreas, and it is considered to be an inherited pancreatic disease.
Many discoveries in SLOS research have been made using animal models. They have been used to study different treatment techniques, including the effectiveness of simvastatin therapy. Other studies have examined behavioural characteristics while attempting to explain their underlying pathogenesis. A common finding is that mouse models of SLOS show abnormal serotonergic development, which may be at least partially responsible for the autistic behaviours seen in SLOS. Mouse models have also been used to develop diagnostic techniques; multiple studies have examined biomarkers that result from the oxidation of 7DHC, such as DHCEO. It is likely that as animal models are improved, they will lead to many more discoveries in SLOS research.
The malabsorption resulting from lack of bile acid has resulted in elemental formula being suggested, which are low in fat with < 3% of calories derived from long chain triglycerides (LCT). However, reduced very long chain fatty acids (VLCFA) has not been shown to reduce blood VLCFA levels , likely because humans can endogenously produce most VLCFA. Plasma VLCFA levels are decreased when dietary VLCFA is reduced in conjunction with supplementation of Lorenzo’s oil (a 4:1 mixture of glyceryl trioleate and glyceryl trierucate) in X-ALD patients . Since docosahexaenoic acid (DHA) synthesis is impaired [59], DHA supplementation was recommended, but a placebo-controlled study has since showed no clinical efficacy . Due to the defective bile acid synthesis, fat soluble supplements of vitamins, A, D, E, and K are recommended.