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

Spinocerebellar ataxia type 6 (SCA6) is a neurological condition characterized by progressive problems with movement. Initial symptoms include problems with coordination and balance (ataxia). Other early signs and symptoms include speech difficulties (dysarthria), involuntary eye movements (nystagmus), and double vision. Over time, individuals with SCA6 may develop loss of coordination in their arms, tremors, and uncontrolled muscle…

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…

X-linked severe combined immunodeficiency (X-SCID) is a severe, genetic condition of the immune system.[1] Signs and symptoms often become apparent in early infancy and include failure to thrive; oral/diaper candidiasis (yeast infection); absent tonsils and lymph nodes; recurrent, persistent infections; rashes; diarrhea; fevers; and pneumonia. X-SCID is caused by mutations in the IL2RG gene and is inherited…

Werner syndrome is a condition that causes premature aging. People with this syndrome will develop and grow normally until puberty. At puberty, growth stops and adults with Werner syndrome are typically shorter than average. By the early 20s-30s, people with this syndrome develop conditions usually associated with more advanced ages. In addition, people with Werner…

Myotonic dystrophy type 2, one of the two types of myotonic dystrophy, is an inherited muscular dystrophy that affects the muscles and other body systems (e.g., heart, eyes, and pancreas). It is characterized by prolonged muscle tensing (myotonia) as well as muscle weakness, pain, and stiffness. Signs and symptoms usually develop during a person’s twenties…

Duane syndrome affects the ability of the eye to move from side to side. Symptoms include restricted movement of eye outward and/or inward and the eyeball may be pulled back into the socket. In addition, the opening of the eye may be narrow. Some people with Duane syndrome develop “lazy eye” (amblyopia), a condition that…

Eisenmenger syndrome (ES) refers to the combination of a type of high blood pressure that affects the blood vessels of the lungs and heart (pulmonary hypertension), and abnormal blood flow through the heart.[1][2] ES most often occurs in people who are born with a heart defect (congenital heart defect) that does not get repaired in…

Wiskott Aldrich syndrome (WAS) is a disease with immunological deficiency and reduced ability to form blood clots. Signs and symptoms include easy bruising or bleeding due to a decrease in the number and size of platelets; susceptibility to infections and to immune and inflammatory disorders; and an increased risk for some cancers (such as lymphoma). Also, a skin condition known as eczema is common in people…

Necrotizing enterocolitis (NEC) is a condition characterized by variable injury or damage to the intestinal tract, causing death of intestinal tissue.[1][2] The condition most often occurs in premature newborns, but it may also occur in term or near-term babies.[2] Signs and symptoms may include abdominal distension, bloody stools, vomiting bile-stained fluid, and pneumatosis intestinalis (gas…

Anaplastic thyroid cancer (ATC) accounts for less than 2% of all thyroid cancers and is the most aggressive type of thyroid cancer.[1] Most cases of anaplastic thyroid cancer are diagnosed in the sixth to seventh decade of life. Women are more likely to be affected than men.[1] ATC generally occurs in individuals with a history…

Idiopathic pulmonary fibrosis (IPF) is a condition in which tissues in the lungs become thick and stiff, or scarred, over time. The lungs then lose their ability to move oxygen to the brain and other parts of the body. Common symptoms include shortness of breath and a dry, hacking cough. In some cases fibrosis happens…

Noonan syndrome is a genetic disorder that causes abnormal development of multiple parts of the body. Features of Noonan syndrome may include a distinctive facial appearance, short stature, a broad or webbed neck, congenital heart defects, bleeding problems, problems with bone structure (skeletal malformations), and developmental delay.[1][2] Noonan syndrome may be caused by a mutation…

Nevoid basal cell carcinoma syndrome (NBCCS) leads to the growth of non-cancerous and cancerous tumors. The symptoms include basal cell cancers, jaw cysts, skin pits on the hands and feet, and abnormal deposits of calcium in the brain. Other symptoms may include bone abnormalities of the spine, ribs, or skull, and a large head. Some of…

X-linked hypophosphatemia (XLH) is an inherited disorder characterized by low levels of phosphate in the blood. Phosphate levels are low because phosphate is abnormally processed in the kidneys, which causes a loss of phosphate in the urine (phosphate wasting) and leads to soft, weak bones (rickets). XLH is usually diagnosed in childhood. Features include bowed…

Central core disease (CCD) is an inherited condition that involves muscle weakness, skeletal abnormalities, and an increased chance of having a severe reaction to some anesthesia medications. Muscle weakness ranges from mild to severe and typically affects muscles in the trunk and upper legs, though muscles in the neck and face can also be affected.[1][2] Skeletal abnormalities…

Klippel Feil syndrome (KFS) is a condition affecting the development of the bones in the spine. People with KFS are born with abnormal fusion of at least two spinal bones (vertebrae) in the neck. Common features may include a short neck, low hairline at the back of the head, and restricted movement of the upper spine….

empty

Lesch Nyhan syndrome is a condition characterized by neurological and behavioral abnormalities and the overproduction of uric acid in the body. It occurs almost exclusively in males. Signs and symptoms may include inflammatory arthritis (gout), kidney stones, bladder stones, and moderate cognitive disability. Nervous system and behavioral disturbances also occur, such as involuntary muscle movements…

Systemic scleroderma is an autoimmune disorder that affects the skin and internal organs. It is characterized by the buildup of scar tissue (fibrosis) in the skin and other organs. The fibrosis is caused by the body’s production of too much collagen, which normally strengthens and supports connective tissues. The signs and symptoms of systemic scleroderma…

Hemophilia A is an inherited bleeding disorder in which the blood does not clot normally.[1][2][3] People with hemophilia A will bleed more than normal after an injury, surgery, or dental procedure. This disorder can be severe, moderate, or mild. In severe cases, heavy bleeding occurs after minor injury or even when there is no injury…

empty

empty

VLCAD deficiency is a condition in which the body is unable to properly breakdown certain fats (called very long-chain fatty acids) into energy, particularly during periods without food (fasting). Signs and symptoms can occur during infancy, childhood or adulthood depending on the form of the condition and may include low blood sugar (hypoglycemia), lack of…

Tyrosine hydroxylase (TH) deficiency is a rare inherited condition that affects the nervous system. There are three different forms of the condition that vary in severity. The mild form is called TH-deficient dopa-responsive dystonia and typically develops between age twelve months and six years. The two severe forms, which are called infantile parkinsonism and progressive infantile encephalopathy, often begin shortly…

Addison’s disease occurs when the adrenal glands do not produce enough (or any) of the hormones, cortisol and aldosterone. These adrenal gland hormones are necessary for balancing water and energy in the body. Symptoms usually develop slowly over time, and may include fatigue, loss of appetite, abdominal pain, and dark patches of skin. Sometimes symptoms…

Lambert Eaton myasthenic syndrome (LEMS) is a disorder of the neuromuscular junction. The neuromuscular junction is the site where nerve cells meet muscle cells and help activate the muscles.[1] This syndrome occurs when antibodies interfere with electrical impulses between the nerve and muscle cells. It may be associated with other autoimmune diseases, or more commonly…

Primary myelofibrosis is a condition characterized by the buildup of scar tissue (fibrosis) in the spongy tissue tissue inside the bone (bone marrow), the tissue that contains the stem cells that will produce blood cells. Because of the fibrosis, the bone marrow is unable to make enough normal blood cells. In myelofibrosis, the bone marrow…

Sturge-Weber syndrome (SWS) is a rare disorder affecting the skin and nervous system. Babies with SWS are born with a birthmark on their face known as a port-wine stain. Port-wine birthmarks are caused by enlarged blood vessels right underneath the skin. People with Sturge-Weber syndrome also have clusters of abnormal blood vessels between the layers…

Progressive supranuclear palsy (PSP) is a degenerative neurologic disease due to damage to nerve cells in the brain.[1] Signs and symptoms vary but may include loss of balance; blurring of vision; problems controlling eye movement; changes in mood, behavior and judgment; cognitive decline; and slowing and slurred speech. PSP is often misdiagnosed as Parkinson disease…

West syndrome is characterized by a specific type of seizure (infantile spasms) seen in infancy and childhood. This syndrome leads to developmental regression and causes a specific pattern, known as hypsarrhythmia (chaotic brain waves), on electroencephalography (EEG) testing. The infantile spasms usually begin in the first year of life, typically between 4-8 months. The seizures primarily consist of a sudden…

Limb-girdle muscular dystrophy type 2A (LGMD2A) is an autosomal recessive limb-girdle muscular dystrophy characterized by progressive, symmetrical weakness of the proximal limb and girdle muscles (mainly those around the hips and shoulders) without heart involvement or intellectual disability.[1][2] The condition is caused by mutations in the CAPN3 gene. Type 2A is the most common form of limb-girdle muscular dystrophy, accounting…

MURCS association stands for (MU)llerian, (R)enal, (C)ervicothoracic (S)omite abnormalities and is a developmental disorder that primarily affects the reproductive and urinary systems. Most individuals with MURCS association are female, although males can also have this condition. Females with MURCS association can have an absent or abnormally shaped uterus. In rare cases, the vagina is also…

Classical Ehlers-Danlos syndrome (EDS) is a genetic connective tissue disorder that is caused by defects in a protein called collagen. Common symptoms include skin hyperextensibility, abnormal wound healing, and joint hypermobility.[1][2] More than 90% of people with classical EDS have mutations in COL5A1 or COL5A2, two genes which encode type V collagen. In rare cases, mutations in the…

Erythropoietic protoporphyria (EPP) is a type of porphyria. Porphyrias are caused by an abnormality in the heme production process. Heme is essential in enabling our blood cells to carry oxygen and in breaking down chemical compounds in the liver. Erythropoietic protoporphyria is caused by pathogenic variants (mutations) in the FECH gene which lead to an impaired…

Anencephaly is a type of neural tube defect characterized by abnormal development of the brain and the bones of the skull. The neural tube is a narrow channel that normally folds and closes between the 3rd and 4th weeks of pregnancy, forming the brain and spinal cord of the embryo. Anencephaly occurs when the ‘cephalic’…

Mucopolysaccharidosis type IIIC (MPS IIIC) is an genetic disorder that makes the body unable to break down large sugar molecules called glycosaminoglycans (GAGs, formerly called mucopolysaccharides).[1][2] Specifically, people with this condition are unable to break down a GAG called heparan sulfate.[2] Affected individuals can have severe neurological symptoms, including progressive dementia, aggressive behavior, hyperactivity, seizures, deafness, loss…

Refsum disease is an inherited condition that causes vision loss, loss of smell (anosmia), and a variety of other signs and symptoms. The vision loss associated with Refsum disease is caused by an eye disorder called retinitis pigmentosa. Other features can include bone abnormalities of the hands and feet; progressive muscle weakness and wasting; poor…

Adenosine deaminase deficiency (ADA deficiency) is an inherited condition that damages the immune system and is a common cause of severe combined immunodeficiency (SCID). People with SCID due to ADA deficiency are unable to fight off most types of infections, including bacterial, viral and fungal infections. Most people with ADA deficiency develop symptoms before 6…

Paroxysmal nonkinesigenic dyskinesia (PNKD) is a disorder of the nervous system that causes periods of involuntary movement. Common symptoms include irregular, jerking or shaking movements, prolonged contraction of muscles, chorea, and/or writhing movements of the limb.[1][2] Symptoms usually last between 1 and 4 hours.[1] The movements may have no known trigger or be brought on by…

empty

Cold agglutinin disease is a rare type of autoimmune hemolytic anemia in which the body’s immune system mistakenly attacks and destroys its own red blood cells. When affected people’s blood is exposed to cold temperatures (32º to 50º F), certain proteins that normally attack bacteria (IgM antibodies) attach themselves to red blood cells and bind…

Nail-patella syndrome causes changes in the nails, elbows, kneecaps (patellae), and hip bone. The most common symptom of the syndrome is having missing or underdeveloped fingernails and toenails. Other symptoms may include having small or missing kneecaps, underdeveloped elbows, and an extra small piece of bone on both sides of the hip (called iliac horns)….

Glycine encephalopathy is an inherited metabolic disease characterized by abnormally high levels of an amino acid called glycine. Glycine is a chemical messenger that transmits signals in the brain.[1][2] According to the symptoms the disease onset, glycine encephalopathy may be divided in:[3][2] Classical neonatal form (most common): Symptoms start within a few days of life and…

Hereditary multiple osteochondromas (HMO), also called hereditary multiple exostoses, is a genetic disorder that causes the development of multiple, cartilage-covered tumors on the external surfaces of bones (osteochondromas). The osteochondromas typically become apparent during childhood or adolescence, and the number, size and location of osteochondromas varies from person to person. Signs and symptoms may include pain,…

Rubinstein-Taybi syndrome (RTS) is a syndrome characterized by broad thumbs and toes, short stature, distinctive facial features, and varying degrees of intellectual disability. The syndrome may be caused by a mutation in the CREBBP or EP300 gene, or as the result of a very small loss (microdeletion) of genetic material from the short (p) arm of chromosome…

Polycystic liver disease is an inherited condition characterized by many cysts of various sizes scattered throughout the liver. Abdominal discomfort from swelling of the liver may occur; however, most affected individuals do not have any symptoms. In some cases, polycystic liver disease appears to occur randomly, with no apparent cause. Most cases are inherited in an…

C syndrome, also known as Opitz trigonocephaly syndrome, is characterized by trigonocephaly, severe intellectual disability, hypotonia, variable cardiac defects, redundant (extra folds of) skin, joint and limb abnormalities, and unusual facial features such as upslanted palpebral fissures (upward pointing outside corners of the eyes), epicanthal folds, depressed nasal bridge, and low-set, posteriorly rotated ears. This…

Common variable immunodeficiency (CVID) is a group of disorders characterized by low levels of a type of protein known as immunoglobulins (Ig). Because of low level of Ig, the immune system cannot make antibodies that fight bacteria, viruses or other toxins in the body.[1] This leads to frequent infections, particularly in the sinuses, lungs, and…

Lamellar ichthyosis is a rare genetic condition that affects the skin. Infants affected by lamellar ichthyosis are generally born with a shiny, waxy layer of skin (called a collodian membrane) that is typically shed within the first two weeks of life. The skin beneath the collodian membrane is red and scaly. Other signs and symptoms…

Histidinemia is an inherited metabolic condition characterized by elevated levels of the amino acid histidine in blood, urine, and cerebrospinal fluid. In most cases, people with this condition have no health problems and may not even know that they are affected. Individuals with histidinemia who also experience a medical complication during or shortly after birth (such as…

Myotonic dystrophy type 1 (MD1), one of the two types of myotonic dystrophy, is an inherited type of muscular dystrophy that affects the muscles and other body systems (e.g., heart, eyes, endocrine system, and central nervous system).[1] MD1 has three forms that somewhat overlap: the mild form, classic form, and congenital form (present at birth). The mild form…

Hermansky-Pudlak syndrome (HPS) affects multiple body systems and includes bleeding and visual problems, and abnormally light coloring of the skin, hair, and eyes (oculocutaneous albinism). Other symptoms may include immune problems, lung scarring (pulmonary fibrosis), and colitis. Symptoms of pulmonary fibrosis may get worse over time, and people with HPS are at increased risk for skin cancer. There…

Kleine Levin syndrome is a rare disorder characterized by recurrent episodes of excessive sleep (hypersomnia) along with cognitive and behavioral changes. Affected individuals may sleep for up to 20 hours per day during an episode. These episodes usually last for a few days to a few weeks. An episode may start abruptly and is sometimes preceded by an upper-respiratory-type…

Familial pancreatic cancer (FPC) is the occurrence of pancreatic cancer in two or more first-degree relatives (parent and child, or two siblings). It is sometimes referred to as FPC only when there is not a known hereditary cancer syndrome in an affected family.[1] In familial cases, pancreatic cancer often occurs before age 50 (earlier than other forms of…

Pseudocholinesterase deficiency is a condition that causes increased sensitivity to certain muscle relaxant drugs used during general anesthesia (choline esters). These drugs relax the muscles used for movement, including those used for breathing. Normally, the muscles are able to move again a few minutes after the drugs are given. People with pseudocholinesterase deficiency may not be…

empty

Propionic acidemia is an inherited condition in which the body can’t breakdown certain parts of proteins and fats. This leads to a build-up of toxic substances and to bouts of serious illness called decompensation events or metabolic crises. Symptoms of a decompensation event include poor feeding, vomiting, weak muscle tone (hypotonia), and lack of energy (lethargy)….

Beta-thalassemia is a blood disorder that reduces the body’s production of hemoglobin. Low levels of hemoglobin lead to a shortage of mature red blood cells and a lack of oxygen in the body. People with beta-thalassemia have anemia, which can cause paleness, weakness, fatigue, and more serious complications.[1] There are two main forms of beta-thalassemia,…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 654 Definition A rare malignant renal tumor, typically affecting the pediatric population, characterized by an abnormal proliferation of cells that resemble the kidney cells of an embryo (metanephroma), leading to the term embryonal tumor. Epidemiology…

Retroperitoneal fibrosis is a slowly progressive disorder in which the tubes that carry urine from the kidneys to the bladder (ureters) and other abdominal organs or vessels become blocked by a fibrous mass and inflammation in the back of the abdomen. The disorder may cause pain in the abdomen that worsens with time, pain or…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 70589 Definition Bronchopulmonary dysplasia is a chronic respiratory disease that results from complications related to lung injury during the treatment of infant acute respiratory distress syndrome (see these terms) in low-birth-weight premature infants or from…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 83419 Definition Proximal spinal muscular atrophy type 3 (SMA3) is a relatively mild form of proximal spinal muscular atrophy (see this term) characterized by muscle weakness and hypotonia resulting from the degeneration and loss of…

Homocystinuria due to CBS deficiency is an inherited disorder in which the body is unable to correctly use the amino acid, homocysteine, one of the building blocks of protein.[1][2][3] This form of homocystinuria is caused by a genetic mutation in the CBS gene, which leads to low levels or absence of an enzyme called cystathionine…

Mitochondrial neurogastrointestinal encephalopathy (MNGIE) syndrome is a condition that mainly affects the digestive system and nervous system. Signs and symptoms most often begin by age 20 and worsen with time.[1] Almost all people with MNGIE have gastrointestinal dysmotility, in which the muscles and nerves of the digestive system do not move food through the digestive tract efficiently…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 3109 Definition Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome describes a spectrum of Mullerian duct anomalies characterized by congenital aplasia of the uterus and upper 2/3 of the vagina in otherwise phenotypically normal females. It can be classified as…

empty

Hereditary angioedema (HAE) is a disease characterized by recurrent episodes (also called attacks) of severe swelling of the skin and mucous membranes.[1] The age at which attacks begin varies, but most people have their first one in childhood or adolescence.[2] The frequency of attacks usually increases after puberty. Attacks most often affect 3 parts of…

Cutaneous Tcell lymphomas (CTCLs) are a group of disorders characterized by an abnormal accumulation of cancerous T-cells (a type of white blood cells) in the skin resulting in an itchy, red rash that can thicken or form a tumor. CTCLs belong to a larger group of disorders known asnon-Hodgkin’s lymphomas. The most common types are mycosis fungoides and Sézary…

Sickle cell anemia is a disease in which the body produces abnormally shaped red blood cells that have a crescent or sickle shape. These cells do not last as long as normal, round, red blood cells, which leads to anemia (low number of red blood cells). The sickle cells also get stuck in blood vessels, blocking blood flow.[1] Signs…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 98808 Definition A rare neurometabolic disorder characterized by childhood-onset dystonia that shows a dramatic and sustained response to low doses of levodopa (L-dopa) and that may be associated with parkinsonism at an older age. Epidemiology…

Dermatomyositis is an autoimmune condition that causes skin changes and muscle weakness. Symptoms can include a red skin rash around the eyelids, red bumps around the joints, and muscle weakness in the arms and legs. Dermatomyositis is most common in adults between ages 40 and 60, or in children between ages 5 and 15. Muscle weakness…

Alkaptonuria is an inherited condition that causes urine to turn black when exposed to air. The three major features of alkaptonuria are the presence of dark urine, ochronosis, a buildup of dark pigment in connective tissues such as cartilage and skin, and arthritis of the spine and larger joints. Ochronosis starts after age 30 and…

Leber congenital amaurosis (LCA) is an eye disorder that primarily affects the retina. People with this condition typically have severe visual impairment beginning in infancy. Other features include photophobia, involuntary movements of the eyes (nystagmus), and extreme farsightedness. The pupils also do not react normally to light. Additionally, the cornea may be cone-shaped and abnormally thin (keratoconus)….

Charcot-Marie-Tooth disease type 1 (CMT1) is a type of peripheral neuropathy, a condition affecting the transmission of information between the central nervous system (brain and spinal cord) and the rest of the body. Symptoms often begin between age 5 and 25, and the condition is usually slowly progressive. Signs and symptoms include distal muscle weakness…

Pure autonomic failure (PAF) is a neurodegenerative disease of the autonomic nervous system, which regulates body processes like blood pressure and breathing rate. PAF usually affects only the peripheral autonomic nervous system, which means it does not usually involve the brain and spinal cord (the central nervous system). Symptoms begin in midlife, although they can begin…

Kabuki syndrome is a rare disorder that affects multiple parts of the body. It is present from birth. Specific symptoms and severity can vary. Features often include a characteristic facial appearance; skeletal abnormalities; short stature; heart defects; and intellectual disability.[1][2] Other signs and symptoms may include seizures, microcephaly, weak muscle tone (hypotonia), eye problems, cleft…

Osteochondritis dissecans is a joint condition that occurs when a piece of cartilage and the thin layer of bone beneath it, separates from the end of the bone. If the piece of cartilage and bone remain close to where they detached, they may not cause any symptoms. However, affected people may experience pain, weakness and/or…

Microscopic polyangiitis (MPA) is a disorder that causes blood vessel inflammation (vasculitis), which can lead to organ damage.[1] The kidneys, lungs, nerves, skin, and joints are the most commonly affected areas of the body. MPA is diagnosed in people of all ages, all ethnicities, and both genders.[2] The cause of this disorder is unknown.

Moyamoya disease is a rare, progressive, blood vessel disease caused by blocked arteries at the base of the brain in an area called the basal ganglia. The name “moyamoya” means “puff of smoke” in Japanese and describes the look of the tangled vessels that form to compensate for the blockage. This condition usually affects children,…

Wolf-Hirschhorn syndrome (WHS) is a genetic disorder that affects many parts of the body. The major features include a characteristic facial appearance, delayed growth and development, intellectual disability, low muscle tone (hypotonia), and seizures. Other features may include skeletal abnormalities, congenital heart defects, hearing loss, urinary tract malformations, and/or structural brain abnormalities. WHS is caused…

Kearns-Sayre syndrome (KSS) is a neuromuscular disorder defined by the triad of onset before age 20 years, pigmentary retinopathy (a “salt-and-pepper” pigmentation in the retina that can affect vision, but often leaves it intact), and progressive external ophthalmoplegia (PEO).[1][2][3] In addition, affected individuals have at least one of the following: cardiac conduction block, cerebrospinal fluid protein concentration…

Miller Fisher syndrome is a rare acquired nerve disease considered to be a variant of Guillain-Barré syndrome.[1] The main features are lack of muscle coordination (ataxia), eye muscle weakness resulting in the inability to move the eyes in several directions (ophthalmoplegia), and the absence of tendon reflexes. Symptoms often start several days after a viral…