MedGen

Gaucher disease (GD) encompasses a continuum of clinical findings from a perinatal lethal disorder to an asymptomatic type. The identification of three major clinical types (1, 2, and 3) and two other subtypes (perinatal-lethal and cardiovascular) is useful in determining prognosis and management. GD type 1 is characterized by the presence of clinical or radiographic evidence of bone disease (osteopenia, focal lytic or sclerotic lesions, and osteonecrosis), hepatosplenomegaly, anemia and thrombocytopenia, lung disease, and the absence of primary central nervous system disease. GD types 2 and 3 are characterized by the presence of primary neurologic disease; in the past, they were distinguished by age of onset and rate of disease progression, but these distinctions are not absolute. Disease with onset before age two years, limited psychomotor development, and a rapidly progressive course with death by age two to four years is classified as GD type 2. Individuals with GD type 3 may have onset before age two years, but often have a more slowly progressive course, with survival into the third or fourth decade. The perinatal-lethal form is associated with ichthyosiform or collodion skin abnormalities or with nonimmune hydrops fetalis. The cardiovascular form is characterized by calcification of the aortic and mitral valves, mild splenomegaly, corneal opacities, and supranuclear ophthalmoplegia. Cardiopulmonary complications have been described with all the clinical subtypes, although varying in frequency and severity. [from GeneReviews]

Tyrosinemia type III (TYRSN3), an autosomal recessive disorder caused by a deficiency in the activity of 4-hydroxyphenylpyruvate dioxygenase (HPD), is characterized by elevated levels of blood tyrosine and massive excretion of its derivatives into urine. Patients with this disorder have mildly impaired intellectual development and/or convulsions, with the absence of liver damage (summary by Tomoeda et al., 2000). [from OMIM]

Congenital bile acid synthesis defect-3 (CBAS3) is an autosomal recessive disorder characterized by prolonged jaundice after birth, hepatomegaly, conjugated hyperbilirubinemia, elevations in characteristic abnormal bile acids, and progressive intrahepatic cholestasis with liver fibrosis (summary by Setchell et al., 1998 and Ueki et al., 2008). For a general phenotypic description and a discussion of genetic heterogeneity of congenital bile acid synthesis defects, see 607765. [from OMIM]

Alkaptonuria is caused by deficiency of homogentisate 1,2-dioxygenase, an enzyme that converts homogentisic acid (HGA) to maleylacetoacetic acid in the tyrosine degradation pathway. The three major features of alkaptonuria are dark urine or urine that turns dark on standing, ochronosis (bluish-black pigmentation in connective tissue), and arthritis of the spine and larger joints. Ochronosis generally occurs after age 30 years; arthritis often begins in the third decade. Other manifestations can include pigment in the sclera, ear cartilage, and skin of the hands; aortic or mitral valve calcification or regurgitation and occasionally aortic dilatation; renal stones; prostate stones; and hypothyroidism. [from GeneReviews]

3-Methylcrotonylglycinuria is an autosomal recessive disorder of leucine catabolism. The clinical phenotype is highly variable, ranging from neonatal onset with severe neurologic involvement to asymptomatic adults. There is a characteristic organic aciduria with massive excretion of 3-hydroxyisovaleric acid and 3-methylcrotonylglycine, usually in combination with a severe secondary carnitine deficiency. MCC activity in extracts of cultured fibroblasts of patients is usually less than 2% of control (summary by Baumgartner et al., 2001). Also see 3-methylcrotonylglycinuria II (MCC2D; 210210), caused by mutation in the beta subunit of 3-methylcrotonyl-CoA carboxylase (MCCC2; 609014). [from OMIM]

3-methylglutaconyl-CoA hydratase deficiency is an inherited condition that causes neurological problems. Beginning in infancy to early childhood, children with this condition often have delayed development of mental and motor skills (psychomotor delay), speech delay, involuntary muscle cramping (dystonia), and spasms and weakness of the arms and legs (spastic quadriparesis). Affected individuals can also have optic atrophy, which is the breakdown (atrophy) of nerve cells that carry visual information from the eyes to the brain.

In some cases, signs and symptoms of 3-methylglutaconyl-CoA hydratase deficiency begin in adulthood, often in a person's twenties or thirties. These individuals have damage to a type of brain tissue called white matter (leukoencephalopathy). This damage likely contributes to progressive problems with speech (dysarthria), difficulty coordinating movements (ataxia), stiffness (spasticity), optic atrophy, and a decline in intellectual function (dementia).

Affected individuals who show symptoms of 3-methylglutaconyl-CoA hydratase deficiency in childhood often go on to develop leukoencephalopathy and other neurological problems in adulthood.

All people with 3-methylglutaconyl-CoA hydratase deficiency accumulate large amounts of a substance called 3-methylglutaconic acid in their body fluids. As a result, they have elevated levels of acid in their blood (metabolic acidosis) and excrete large amounts of acid in their urine (aciduria). 3-methylglutaconyl-CoA hydratase deficiency is one of a group of metabolic disorders that can be diagnosed by the presence of increased levels 3-methylglutaconic acid in urine (3-methylglutaconic aciduria). People with 3-methylglutaconyl-CoA hydratase deficiency also have high urine levels of another acid called 3-methylglutaric acid. [from MedlinePlus Genetics]

3-Methylcrotonylglycinuria is an autosomal recessive disorder of leucine catabolism. The clinical phenotype is highly variable, ranging from neonatal onset with severe neurologic involvement to asymptomatic adults. There is a characteristic organic aciduria with massive excretion of 3-hydroxyisovaleric acid and 3-methylcrotonylglycine, usually in combination with a severe secondary carnitine deficiency. MCC activity in extracts of cultured fibroblasts of patients is usually less than 2% of control (summary by Baumgartner et al., 2001). Also see 3-methylcrotonylglycinuria I (MCC1D; 210200), caused by mutation in the alpha subunit of 3-methylcrotonyl-CoA carboxylase (MCCC1; 609010). [from OMIM]

3-Methylglutaconic aciduria type V (MGCA5) is an autosomal recessive disorder characterized by the onset of dilated or noncompaction cardiomyopathy in infancy or early childhood. Many patients die of cardiac failure. Other features include microcytic anemia, growth retardation, mild ataxia, mild muscle weakness, genital anomalies in males, and increased urinary excretion of 3-methylglutaconic acid. Some patients may have optic atrophy or delayed psychomotor development (summary by Davey et al., 2006 and Ojala et al., 2012). For a discussion of genetic heterogeneity of 3-methylglutaconic aciduria, see MGCA type I (250950). [from OMIM]

The major clinical features of maple syrup urine disease (MSUD) are mental and physical retardation, feeding problems, and a maple syrup odor to the urine. The keto acids of the branched-chain amino acids (BCAA) are present in the urine, resulting from a block in oxidative decarboxylation. There are 4 clinical subtypes of MSUD1B: the classic neonatal severe form, an intermediate form, an intermittent form, and a thiamine-responsive form (Chuang and Shih, 2001). The classic form is manifested within the first 2 weeks of life with poor feeding, lethargy, seizures, coma, and death if untreated. Intermediate MSUD is associated with elevated BCAAs and BCKA, with progressive mental retardation and developmental delay without a history of catastrophic illness. The diagnosis is usually delayed for many months. An intermittent form of MSUD may have normal levels of BCAAs, normal intelligence and development until a stress, e.g., infection, precipitates decompensation with ketoacidosis and neurologic symptoms, which are usually reversed with dietary treatment. Thiamine-responsive MSUD is similar to the intermediate phenotype but responds to pharmacologic doses of thiamine with normalization of BCAAs (Chuang et al., 1995). For general phenotypic information and a discussion of genetic heterogeneity of MSUD, see MSUD1A (248600). [from OMIM]

3-Hydroxyisobutyryl-CoA hydrolase deficiency (HIBCHD) is an autosomal recessive inborn error of metabolism characterized by severely delayed psychomotor development, neurodegeneration, increased lactic acid, and brain lesions in the basal ganglia (summary by Ferdinandusse et al., 2013). [from OMIM]

Rhizomelic chondrodysplasia punctata (RCDP) is a peroxisomal disorder characterized by disproportionately short stature primarily affecting the proximal parts of the extremities, a typical facial appearance including a broad nasal bridge, epicanthus, high-arched palate, dysplastic external ears, and micrognathia, congenital contractures, characteristic ocular involvement, dwarfism, and severe mental retardation with spasticity. Biochemically, plasmalogen synthesis and phytanic acid alpha-oxidation are defective. Most patients die in the first decade of life. RCDP1 is the most frequent form of RCDP (summary by Wanders and Waterham, 2005). Whereas RCDP1 is a peroxisomal biogenesis disorder (PBD), RCDP3 is classified as a single peroxisome enzyme deficiency (Waterham and Ebberink, 2012). For a discussion of genetic heterogeneity of rhizomelic chondrodysplasia punctata, see 215100. [from OMIM]

Congenital bile acid synthesis defect type 2 is a disorder characterized by cholestasis, a condition that impairs the production and release of a digestive fluid called bile from liver cells. Bile is used during digestion to absorb fats and fat-soluble vitamins, such as vitamins A, D, E, and K. People with congenital bile acid synthesis defect type 2 cannot produce (synthesize) bile acids, which are a component of bile that stimulate bile flow and help it absorb fats and fat-soluble vitamins. As a result, an abnormal form of bile is produced.

The signs and symptoms of congenital bile acid synthesis defect type 2 often develop in infancy. Affected infants usually have a failure to gain weight and grow at the expected rate (failure to thrive) and yellowing of the skin and eyes (jaundice) due to impaired bile flow and a buildup of partially formed bile. Excess fat in the feces (steatorrhea) is another feature of congenital bile acid synthesis defect type 2. As the condition progresses, affected individuals can develop liver abnormalities including inflammation or chronic liver disease (cirrhosis). Some individuals with congenital bile acid synthesis defect type 2 cannot absorb certain fat-soluble vitamins, which can result in softening and weakening of the bones (rickets) or problems with blood clotting that lead to prolonged bleeding.

If left untreated, congenital bile acid synthesis defect type 2 typically leads to cirrhosis and death in childhood. [from MedlinePlus Genetics]

The two forms of deoxyguanosine kinase (DGUOK) deficiency are a neonatal multisystem disorder and an isolated hepatic disorder that presents later in infancy or childhood. The majority of affected individuals have the multisystem illness with hepatic disease (jaundice, cholestasis, hepatomegaly, and elevated transaminases) and neurologic manifestations (hypotonia, nystagmus, and psychomotor retardation) evident within weeks of birth. Those with isolated liver disease may also have renal involvement and some later develop mild hypotonia. Progressive hepatic disease is the most common cause of death in both forms. [from GeneReviews]

Congenital defects of bile acid synthesis are autosomal recessive disorders characterized by neonatal onset of progressive liver disease with cholestatic jaundice and malabsorption of lipids and lipid-soluble vitamins from the gastrointestinal tract resulting from a primary failure to synthesize bile acids. Affected infants show failure to thrive and secondary coagulopathy. In most forms of the disorder, there is a favorable response to oral bile acid therapy (summary by Cheng et al., 2003). Genetic Heterogeneity of Congenital Defects in Bile Acid Synthesis There are several disorders that result from defects in bile acid synthesis. See CBAS2 (235555), caused by mutation in the delta(4)-3-oxosteroid 5-beta-reductase gene (AKR1D1; 604741) on chromosome 7q33; CBAS3 (613812), caused by mutation in the 7-alpha hydroxylase gene (CYP7B1; 603711) on chromosome 8q12; CBAS4 (214950), caused by mutation in the AMACR gene (604489) on chromosome 5p13; CBAS5 (616278), caused by mutation in the ABCD3 gene (170995) on chromosome 1p21; and CBAS6 (617308), caused by mutation in the ACOX2 gene (601641) on chromosome 3p14. See also progressive familial intrahepatic cholestasis (PFIC1; 211600), which has a similar phenotype. [from OMIM]

An increased amount of 3-hydroxybutyric acid in the urine. [from HPO]

Deficiency of all vitamin K-dependent clotting factors leads to a bleeding tendency that is usually reversed by oral administration of vitamin K. Acquired forms of the disorder can be caused by intestinal malabsorption of vitamin K. Familial multiple coagulation factor deficiency is rare. Clinical symptoms of the disease include episodes of intracranial hemorrhage in the first weeks of life, sometimes leading to a fatal outcome. The pathomechanism is based on a reduced hepatic gamma-carboxylation of glutamic acid residues of all vitamin K-dependent blood coagulation factors, as well as the anticoagulant factors protein C (612283) and protein S (176880). Posttranslational gamma-carboxylation of proteins enables the calcium-dependent attachment of the proteins to the phospholipid bilayer of membranes, an essential prerequisite for blood coagulation. Vitamin K1 acts as a cofactor for the vitamin K-dependent carboxylase in liver microsomes, GGCX. Genetic Heterogeneity of Combined Deficiency of Vitamin K-Dependent Clotting Factors Combined deficiency of vitamin K-dependent clotting factors-2 (VKFCD2; 607473) is caused by mutation in the gene encoding vitamin K epoxide reductase (VKORC1; 608547) on chromosome 16p11. [from OMIM]

An increased amount of 3-aminoisobutyric acid in the urine. [from HPO]

D-bifunctional protein deficiency is a disorder of peroxisomal fatty acid beta-oxidation. See also peroxisomal acyl-CoA oxidase deficiency (264470), caused by mutation in the ACOX1 gene (609751) on chromosome 17q25. The clinical manifestations of these 2 deficiencies are similar to those of disorders of peroxisomal assembly, including X-linked adrenoleukodystrophy (ALD; 300100), Zellweger cerebrohepatorenal syndrome (see 214100) and neonatal adrenoleukodystrophy (NALD; see 601539) (Watkins et al., 1995). DBP deficiency has been classified into 3 subtypes depending upon the deficient enzyme activity. Type I is a deficiency of both 2-enoyl-CoA hydratase and 3-hydroxyacyl-CoA dehydrogenase; type II is a deficiency of hydratase activity alone; and type III is a deficiency of dehydrogenase activity alone. Virtually all patients with types I, II, and III have a severe phenotype characterized by infantile-onset of hypotonia, seizures, and abnormal facial features, and most die before age 2 years. McMillan et al. (2012) proposed a type IV deficiency on the basis of less severe features; these patients have a phenotype reminiscent of Perrault syndrome (PRLTS1; 233400). Pierce et al. (2010) noted that Perrault syndrome and DBP deficiency overlap clinically and suggested that DBP deficiency may be underdiagnosed. [from OMIM]

Primary bile acid malabsorption (PBAM) is an intestinal disorder associated with chronic watery diarrhea, excess fecal bile acids, and steatorrhea. Bile acid malabsorption has been classified into 3 main types depending on the etiology. Types 1 and 3 are secondary disorders: type 1 is due to ileal dysfunction resulting from Crohn disease or ileal resection, and type 3 is secondary to other conditions, including cholecystectomy, post-vagotomy, celiac disease, and pancreatic insufficiency. Type 2 bile acid malabsorption is a primary congenital disorder, including the rare type due to mutations in the SLC10A2 gene (review by Pattni and Walters, 2009). Genetic Heterogeneity of Primary Bile Acid Malabsorption Also see PBAM2 (619481), caused by mutation in the SLC51B gene (612085). [from OMIM]

Intrahepatic cholestasis of pregnancy is a reversible form of cholestasis that occurs most often in the third trimester of pregnancy and recurs in 45 to 70% of subsequent pregnancies. Symptoms include pruritus, jaundice, increased serum bile salts, and abnormal liver enzymes, all of which resolve rapidly after delivery. However, the condition is associated with fetal complications, including placental insufficiency, premature labor, fetal distress, and intrauterine death. Women with ICP are also susceptible to oral contraceptive-induced cholestasis (OCIC). Ursodeoxycholic acid (UDCA) is an effective treatment for conditions caused by ABCB4 mutations (summary by Pasmant et al., 2012). Mutation in the ABCB4 gene accounts for about 15% of ICP cases (summary by Ziol et al., 2008). For a discussion of genetic heterogeneity of ICP, see ICP1 (147480). [from OMIM]