Pseudohypoparathyroidism is a genetic disorder in which the body is unable to respond to parathyroid hormone. Parathyroid hormone helps control calcium, phosphorous, and vitamin D levels in the bones and blood. Hypoparathyroidism is a similar condition in which the body does not make enough parathyroid hormone instead of not being able to respond to it (as in pseudohypoparathyroidism).[1] The…

Sideroblastic anemia pyridoxine-refractory autosomal recessive is an inherited blood disorder that is characterized by an impaired ability of the bone marrow to produce normal red blood cells. The iron inside red blood cells is inadequately used to make hemoglobin, despite adequate or increased amounts of iron. Abnormal red blood cells called sideroblasts are found in the…

Saethre-Chotzen syndrome is a genetic condition characterized by the premature fusion of certain skull bones (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape and symmetry of the head and face. Other features may include webbing of certain fingers or toes (syndactyly), small or unusually shaped ears, short stature, and…

48,XXXY syndrome is a type of chromosome abnormality characterized by the presence of 2 extra X chromosomes in males. It is sometimes referred to as a variant of Klinefelter syndrome, but differs from Klinefelter syndrome in many ways and is more severe.[1] Signs and symptoms of 48,XXXY syndrome can vary but may include learning difficulties; intellectual…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 404 Definition Familial hyperaldosteronism type II (FH-II) is a heritable form of primary aldosteronism (PA) characterized by hypertension of varying severity, and non glucocticoid remediable hyperaldosteronism. Epidemiology PA is the most common form of secondary…

Gastrointestinal stromal tumors (GIST) are a type of soft tissue tumor that usually begin in specialized nerve cells in the wall of the stomach, intestines, or rectum, known as interstitial cells of Cajal. GIST may be noncancerous (benign) or cancerous (malignant). If cancerous, the tumor may also be called a soft tissue sarcoma. Symptoms depend on the location,…

Langerhans cell histiocytosis (LCH) is a disorder that primarily affects children, but is also found in adults of all ages. People with LCH produce too many Langerhans cells or histiocytes, a form of white blood cell found in healthy people that is supposed to protect the body from infection. In people with LCH, these cells multiply excessively and build up…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 93473 Definition Hurler syndrome is the most severe form of mucopolysaccharidosis type 1 (MPS1; see this term), a rare lysosomal storage disease, characterized by skeletal abnormalities, cognitive impairment, heart disease, respiratory problems, enlarged liver and…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 119 Definition A subtype of autosomal recessive limb girdle muscular dystrophy characterized by a childhood to adolescent onset of progressive pelvicand shoulder-girdle muscle weakness, particularly affecting the pelvic girdle (adductors and flexors of hip). Usually…

Sarcosinemia is a rare inborn error of metabolism characterized by an increased level of the amino acid sarcosine in the blood and urine.[1] It is reportedly most likely benign, unrelated to significant signs or symptoms.[2][3][4] A number of children have been detected by newborn screening and have remained symptom-free.[5] Some reports have associated sarcosinemia with various symptoms…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 42062 Definition Iminoglycinuria is a metabolic disorder resulting from defective renal tube reabsorption of proline, hydroxyproline and glycine. The prevalence is estimated at around 1 in 15 000. The disorder is usually asymptomatic and is…

Lymphangioleiomyomatosis (lim-FAN-je-o-LI-o-MI-o-ma-TO-sis), or LAM, is a rare cystic lung disease that mostly affects women in their mid-forties. In LAM, an unusual type of cell begins to grow out of control throughout the body, including in the lungs, lymph nodes and vessels, and kidneys. Over time, these LAM cells form cysts and clusters of cells, which…

empty

Cowden syndrome is an inherited condition that is characterized primarily by multiple, noncancerous growths (called hamartomas) on various parts of the body. People with the syndrome usually have large head (macrocephaly), benign tumors of the hair follicle (trichilemmomas), and white papules with a smooth surface in the mouth (papillomatous papules), starting by the late 20s. It is considered part…

Trisomy 18 is a chromosome disorder characterized by having 3 copies of chromosome 18 instead of the usual 2 copies. Signs and symptoms include severe intellectual disability; low birth weight; a small, abnormally shaped head; a small jaw and mouth; clenched fists with overlapping fingers; congenital heart defects; and various abnormalities of other organs. Trisomy…

Spinal muscular atrophy 1 (SMA1), also known as Werdnig Hoffmann disease, is a genetic neuromuscular disorder that affects the nerve cells that control voluntary muscles (motor neurons). Without treatment, symptoms of SMA1 become apparent before 6 months of age and include worsening muscle weakness and poor muscle tone (hypotonia) due to loss of the lower…

Creutzfeldt-Jakob disease (CJD) is a rare fatal brain disorder that usually occurs later in life and runs a rapid course. In the early stages of the disease, patients may have failing memory, behavior changes, impaired coordination, and vision problems. As CJD progresses, mental deterioration becomes severe, and they can have uncontrolled movements, blindness, weakness, and go into…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 100070 Definition Progressive non-fluent aphasia (PNFA) is a form of frontotemporal dementia (FTD; see this term), characterized by agrammatism, laborious speech, alexia, and agraphia, frequently accompanied by apraxia of speech (AOS). Language comprehension is relatively…

empty

Leishmaniasis is a parasitic disease spread by the bite of infected sand flies. There are several different forms of leishmaniasis. The most common are cutaneous and visceral. The cutaneous type causes skin sores. The visceral type affects internal organs such as the spleen, liver and bone marrow. People with this form usually have fever, weight…

Diastrophic dysplasia is a disorder of cartilage and bone development.[1] Diastrophic dysplasia is characterized by shortened arms and legs, spinal deformities, hitchhiker thumbs, joint contractures, and joint pain (osteoarthritis).[2] Joint contractures and spinal deformity tend to worsen with age.[2] Mental development and intelligence are usually normal.[2] Occasionally, children with diastrophic dysplasia die in infancy due…

empty

Stickler syndrome is a group of hereditary connective tissue disorders characterized by distinctive facial features, eye abnormalities, hearing loss, and joint problems. The symptoms of Stickler syndrome may vary but include near-sightedness (myopia), retinal detachment, underdevelopment of the middle of the face, and the development of arthritis at a young age.[1] Stickler syndrome is caused…

Sudden sensorineural deafness is a condition that is characterized by rapid, unexplained hearing loss. More specifically, affected people experience a reduction in hearing of greater than 30 decibels, which may occur all at once or over several days. In most cases, only one ear is affected. People with sudden sensorineural deafness often become dizzy, have…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 95720 Definition Thyroid hypoplasia is a form of thyroid dysgenesis (see this term) characterized by incomplete development of the thyroid gland that results in primary congenital hypothyroidism (see this term), a permanent thyroid deficiency that…

Adult-onset Still’s disease (AOSD) is an inflammatory condition that affects multiple organs. The most common symptoms are high fevers, skin rash, arthritis, and high levels of ferritin, a protein that stores iron in the blood. Other symptoms include an enlarged spleen and lymph nodes, joint pain, and sore throat. In some cases, symptoms may be…

Warm antibody hemolytic anemia is the most common form of autoimmune hemolytic anemia. It is defined by the presence of autoantibodies that attach to and destroy red blood cells at temperatures equal to or greater than normal body temperature.[1][2] The disease is characterized by symptoms related to anemia, including fatigue, difficulty breathing, jaundice and dark urine. In severe disease, fever, chest pain, syncope or…

Osteopetrosis refers to a group of rare, inherited skeletal disorders characterized by increased bone density and abnormal bone growth.[1][2] Symptoms and severity can vary greatly, ranging from neonatal onset with life-threatening complications (such as bone marrow failure) to the incidental finding of osteopetrosis on X-ray. Depending on severity and age of onset, features may include fractures, short stature,…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 36899 Definition Myoclonusdystonia syndrome (MDS) is a rare movement disorder characterized by mild to moderate dystonia along with ‘lightning-like’ myoclonic jerks. Epidemiology The estimated prevalence of MDS in Europe is 1/500,000. Clinical description Disease onset…

Alpha-thalassemia is a blood disorder that reduces the body’s production of hemoglobin. Affected people have anemia, which can cause pale skin, weakness, fatigue, and more serious complications. Two types of alpha-thalassemia can cause health problems: the more severe type is known as Hb Bart syndrome; the milder form is called HbH disease. Hb Bart syndrome…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 2019 Definition Femur-fibula-ulna (FFU) complex is a non-lethal congenital anomaly of unknown etiology, more frequently reported in males than females, characterized by a highly variable combination of defects of the femur, fibula, and/or ulna, with…

Hydrocephalus due to congenital stenosis of aqueduct of sylvius (HSAS) is a form of L1 syndrome, which is an inherited disorder that primarily affects the nervous system. Males with HSAS are typically born with severe hydrocephalus and adducted thumbs (bent towards the palm). Other sign and symptoms of the condition include severe intellectual disability and…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 30391 Definition Biliary atresia is a rare, progressive obliterative cholangiopathy of the extrahepatic bile ducts, occuring in the embryonic/ perinatal period, leading to severe and persistent jaundice and acholic stool with an unfavorable course in…

Caudal regression sequence (CRS) affects the development of the lower (caudal) half of the body. It can impact the development of the lower back, spinal cord, and lower limbs. The kidneys, bladder, digestive tract, and genitalia may also be affected. CRS occurs during fetal development and is present at birth. The features and severity vary from…

Lowe oculocerebrorenal syndrome is a rare condition that primarily affects the eyes, central nervous system and kidneys. Some of the signs and symptoms associated with the condition are often present from birth, including congenital cataracts and other eye abnormalities; hypotonia (reduced muscle tone); and feeding difficulties. Affected people may also experience kidney problems (such as…

Cystic fibrosis (CF) is a genetic disorder that causes mucus to build up and damage organs in the body, particularly the lungs and pancreas. Signs and symptoms may include salty-tasting skin; persistent coughing; frequent lung infections; wheezing or shortness of breath; poor growth; weight loss; greasy, bulky stools; difficulty with bowel movements; and in males, infertility. Over time,…

Multiple endocrine neoplasia type 2 (MEN2) is an inherited disorder in which one or more of the endocrine glands are overactive or form a tumor. Endocrine glands most commonly involved include:[1] Adrenal (about half the time) Parathyroid (20% of the time) Thyroid (almost all of the time) MEN2 is caused by a defect in the RET gene.[1][2] This defect…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 289560 Definition A rare neurodegenerative disorder characterized by iron accumulation in specific regions of the brain, usually the basal ganglia, and associated with slowly progressive pyramidal (spasticity) and extrapyramidal (dystonia) signs, motor axonal neuropathy, optic…

Multiple system atrophy (MSA) causes the progressive loss of nerve cells in the brain (a neurodegenerative disease). MSA affects several areas of the brain, including the cerebellum, which is involved in controlling movement and some emotions, as well as certain types of learning and memory, and the autonomic nervous system, which controls your body’s automatic, or…

Neurofibromatosis type 1 (NF1) is a genetic condition that affects the skin, the skeleton and the part of the nervous system outside the brain and spinal cord peripheral nervous system). The main signs and symptoms of NF1 include dark colored spots on the skin (café-au-lait spots), benign growths along the nerves (neurofibromas), and freckles in…

Medium-chain acyl-coenzyme A dehydrogenase deficiency (MCADD) is an inherited metabolic disorder that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). People with MCADD do not have enough of an enzyme needed to metabolize a group of fats called medium-chain fatty acids. Signs and symptoms usually begin by early…

Inclusion body myopathy 2, also known as hereditary inclusion body myopathy (HIBM), GNE-related myopathy, distal myopathy with rimmed vacuoles, and Nonaka myopathy, is an inherited condition that primarily affects the skeletal muscles (the muscles that the body uses to move). This disorder is characterized by muscle weakness that appears in late adolescence or early adulthood and worsens over time.[1] Early…

Dopa-responsive dystonia (DRD) is an inherited type of dystonia that typically begins during childhood but may begin in adolescence or adulthood.[1] Depending on the specific type of DRD, specific symptoms can vary. Features can range from mild to severe. In most cases, dystonia begins in the lower limbs and spreads to the upper limbs over…

AL amyloidosisis the most common form of amyloidosis, a group of disorders in which an abnormal protein called amyloid builds up in tissues and organs. The signs and symptoms of AL amyloidosis vary among patients because the build up may occur in the tongue, intestines, muscles, joints, nerves, skin, ligaments, heart, liver, spleen, or kidneys. To diagnose AL…

Alström syndrome is a rare genetic disorder that affects many body systems.[1][2] Symptoms develop gradually, beginning in infancy, and can be variable. In childhood, the disorder is generally characterized by vision and hearing abnormalities, childhood obesity, and heart disease (cardiomyopathy). Over time, diabetes mellitus, liver problems, and slowly progressive kidney dysfunction which can lead to kidney…

Familial or sporadic hemiplegic migraine refers to a rare type of migraine with aura that occurs with motor weakness during the aura. The two types of hemiplegic migraine (HM) are distinguished based on the family history: familial hemiplegic migraine (FHM, in which at least one other family member has the condition) and sporadic hemiplegic migraine (SHM, in which there is no…

Ataxia with vitamin E deficiency (AVED) is a progressive disease affecting motor control and movement. Symptoms of AVED include slurred speech (dysarthria), difficulty coordinating movements (ataxia), numbness in the hands and feet (peripheral neuropathy), and progressive leg weakness. Some affected individuals may experience vision loss due to damage to the back of the eye (retinitis…

Kaposi sarcoma (KS) is a cancer that develops from the cells that line lymph or blood vessels. It usually appears as tumors on the skin or on mucosal surfaces such as inside the mouth, but tumors can also develop in other parts of the body (including the lymph nodes, lungs, or digestive tract). The abnormal…

Calciphylaxis is a disease in which blood vessels (veins and arteries) become blocked by a build-up of calcium in the walls of the vessels, preventing blood from flowing to the skin or internal organs. The lack of blood flow (ischemia) damages healthy tissue and causes it to die (necrosis). The most obvious and frequent symptom of…

Central diabetes insipidus (DI) is a form of DI that occurs when the body has lower than normal levels of antidiuretic hormone (vasopressin), which is characterized by frequent urination.[1][2] Diabetes insipidus is subdivided into central and nephrogenic DI. Two other forms are gestational DI and primary polydipsia (dipsogenic DI). Central DI results from damage to the…

Trisomy 13 is a type of chromosome disorder characterized by having 3 copies of chromosome 13 in cells of the body, instead of the usual 2 copies. In some people, only a portion of cells contains the extra chromosome 13 (called mosaic trisomy 13), whereas other cells contain the normal chromosome pair.[1][2][3] Trisomy 13 causes…

Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency (classic 21-OHD CAH) affects the adrenal glands which are responsible for producing specific hormones. There are two types of classic 21-OHD CAH, the salt-wasting form and the simple-virilizing form. Symptoms include abnormal development of the external sex organs in females (ambiguous genitalia), early puberty, and short stature. The…

empty

Achalasia is a disorder of the esophagus, the tube that carries food from the mouth to the stomach. It is characterized by enlargement of the esophagus, impaired ability of the esophagus to push food down toward the stomach (peristalsis), and failure of the ring-shaped muscle at the bottom of the esophagus (the lower esophageal sphincter) to relax.[1] Achalasia is…

ACTH-secreting pituitary adenoma is a condition characterized by elevated levels of a hormone called cortisol secreted by a tumor in the pituitary gland. It is part of a group of diseases that cause Cushing’s syndrome, characterized by signs and symptoms that may include weight gain around the trunk and in the face, stretch marks, easy bruising, a hump on…

Myotonic dystrophy is a disease that affects the muscles and other body systems. It is the most common form of muscular dystrophy that begins in adulthood, usually in a person’s 20s or 30s. This disease is characterized by progressive muscle loss and weakness. Myotonic dystrophy may be further classified into two types, and the two…

Ebstein’s anomaly is a rare heart defect in which parts of the tricuspid valve (which separates the right ventricle from the right atrium) are abnormal. The abnormality causes the tricuspid valve to leak blood backwards into the right atrium. The backup of blood flow can lead to heart swelling and fluid buildup in the lungs…

Amyotrophic lateral sclerosis (ALS), also referred to as “Lou Gehrig’s disease,” is a progressive motor neuron disease which leads to problems with muscle control and movement.[1][2] There are various types of ALS that are distinguished by symptoms and, in some cases, genetic cause.[2] Early symptoms may include muscle twitching, cramping, stiffness, or weakness, slurred speech,…

Phenylketonuria (PKU) is a genetic metabolic disorder that increases the body’s levels of phenylalanine. Phenylalanine is one of the building blocks (amino acids) of proteins. Humans cannot make phenyalanine, but it is a natural part of the foods we eat. However, people do not need all the phenyalanine they eat, so the body converts extra…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 93476 Definition Hurler-Scheie syndrome is the intermediate form of mucopolysaccharidosis type 1 (MPS1; see this term) between the two extremes Hurler syndrome and Scheie syndrome (see these terms); it is a rare lysosomal storage disease,…

Turner syndrome is a chromosomal disorder that affects development in females. It results when a female’s cells have one normal X chromosome and the other sex chromosome is either missing or structurally altered (females without Turner syndrome have two normal X chromosomes in each cell, and males have one X and one Y chromosome). Signs and symptoms…

Juvenile retinoschisis is an eye condition characterized by impaired vision that begins in childhood and occurs almost exclusively in males. The condition affects the retina, which is a specialized light-sensitive tissue that lines the back of the eye. This affects the sharpness of vision. Central vision is more commonly affected. Vision often deteriorates early in…

Lysosomal acid lipase deficiency is a metabolic lipid storage disease.[1][2] Two rare conditions may result from this deficiency (likely representing two ends of a clinical spectrum):[1][3] Wolman disease: The early-onset and most severe form of the disease where lipids accumulate throughout the body, mostly in the liver, within the first weeks of life. Symptoms include…

Jervell Lange-Nielsen syndrome (JLNS) is an inherited disorder characterized by deafness present at birth and abnormalities of the electrical system of the heart. It is a form of long QT syndrome. This refers to the QT interval measurement seen on the electrocardiogram. The severity of cardiac symptoms seen in individuals varies from no apparent symptoms to increasing…

Joubert syndrome is disorder of brain development that may affect many parts of the body. It is characterized by the absence or underdevelopment of the cerebellar vermis (a part of the brain that controls balance and coordination) and a malformed brain stem (connection between the brain and spinal cord). Together, these cause the characteristic appearance of…

Choroideremia is a genetic condition that causes vision loss. This disorder typically affects males. The first symptom is usually impairment of night vision (night blindness), which can occur in childhood. People with this disorder also experience narrowing of the field of vision (tunnel vision) and decrease in the ability to see details (visual acuity). The…

Ocular albinism type 1 (OA1) is a genetic eye condition that primarily affects males. Signs and symptoms may include reduced coloring of the iris and retina (ocular hypopigmentation); foveal hypoplasia (underdevelopment); rapid, involuntary eye movements (nystagmus); poor vision; poor depth perception; eyes that do not look in the same direction (strabismus); and increased sensitivity to…

Nontuberculous mycobacterial (NTM) lung disease is an infectious condition caused by certain types of mycobacteria. Some people with NTM lung disease have no signs or symptoms, while others experience a severe cough, hemoptysis (coughing up blood), shortness of breath, fatigue, fever, night sweats and/or weightloss. Mycobacteria are found naturally in soil and water. Most people…

Friedreich ataxia is an inherited condition that affects the nervous system and causes movement problems. People with this condition develop impaired muscle coordination (ataxia) that worsens over time. Other features include the gradual loss of strength and sensation in the arms and legs, muscle stiffness (spasticity), and impaired speech. Many individuals have a form of heart…

Ectodermal dysplasias (ED) are a group of more than 180 disorders that affect the outer layer of tissue of the embryo (ectoderm) that helps make up the skin, sweat glands, hair, teeth, and nails. Symptoms of ED can range from mild to severe and may include teeth abnormalities; brittle, sparse or absent hair; abnormal fingernails;…

Congenital adrenal hyperplasia (CAH) refers to a group of genetic conditions that affect the adrenal glands. These glands sit on top of the kidneys and are responsible for releasing various types of hormones that the body needs to function. Affected people lack an enzyme the adrenal glands need to make one or more of these…

Rett syndrome is a progressive, neuro-developmental condition that primarily affects girls. Affected girls appear to have normal psychomotor development during the first 6 to 18 months of life, followed by a developmental “plateau,” and then rapid regression in language and motor skills. Additional signs and symptoms may include repetitive, stereotypic hand movements; fits of screaming…

Spinal muscular atrophy (SMA) is a group of genetic neuromuscular disorders that affect the nerve cells that control voluntary muscles (motor neurons). The loss of motor neurons causes progressive muscle weakness and loss of movement due to muscle wasting (atrophy). The severity of the symptoms, the age at which symptoms, begin, and genetic cause varies…

Focal segmental glomerulosclerosis (FSGS) is a type of kidney disorder. It is characterized by scar tissue that forms in some of the glomeruli in the kidney.[1] FSGS may cause non-specific signs and symptoms, including protein in the urine, elevated levels of creatinine, and swelling.[2][3] In many cases the cause of FSGS can not be determined. Some…

Immune thrombocytopenic purpura (ITP) is a bleeding disorder characterized by too few platelets in the blood. This is because platelets are being destroyed by the immune system. Symptoms may include bruising, nosebleed or bleeding in the mouth, bleeding into the skin, and abnormally heavy menstruation. With treatment, the chance of remission (a symptom-free period) is…

Lennox-Gastaut syndrome is a form of severe epilepsy that begins in childhood. It is characterized by multiple types of seizures and intellectual disability.[1] This condition can be caused by brain malformations, perinatal asphyxia (lack of oxygen), severe head injury, central nervous system infection and inherited degenerative or metabolic conditions. In about one-third of cases, no…

Autoimmune hemolytic anemia (AIHA) occurs when your immune system makes antibodies that attack your red blood cells. This causes a drop in the number of red blood cells, leading to hemolytic anemia.[1][2][3][4] Symptoms may include unusual weakness and fatigue with tachycardia and breathing difficulties, jaundice, dark urine and/or splenomegaly. AIHA can be primary (idiopathic) or result from…

IgA nephropathy is a kidney disorder that occurs when IgA (immunoglobulin A), a protein that helps the body fight infections, settles in the kidneys. IgA nephropathy can occur at any age, even in childhood. After many years, deposits of IgA may cause the kidneys to leak blood and sometimes protein in the urine. In the early…

Narcolepsy is a chronic brain disorder that involves poor control of sleep-wake cycles. People with narcolepsy have episodes of extreme daytime sleepiness and sudden, irresistible bouts of sleep (called “sleep attacks”) that can occur at any time, and may last from seconds or minutes. Other signs and symptoms may include cataplexy (a sudden loss of…