Juvenile Huntington disease (HD) is a less common, early-onset form of Huntington disease that begins in childhood or adolescence. It is a progressive disorder that causes the breakdown of brain cells in certain areas of the brain. This results in uncontrolled movements, loss of intellectual abilities, and emotional disturbances. Juvenile HD is defined by the onset…

Inclusion body myositis (IBM) is a progressive muscle disorder characterized by muscle inflammation, weakness, and atrophy (wasting). It is a type of inflammatory myopathy. IBM develops in adulthood, usually after age 50. The symptoms and rate of progression vary from person to person. The most common symptoms include progressive weakness of the legs, arms, fingers, and…

CADASIL (Cerebral Autosomal Dominant Arteriopathy with Sub-cortical Infarcts and Leukoencephalopathy) is an inherited disease of the blood vessels that occurs when the thickening of blood vessel walls blocks the flow of blood to the brain. The disease primarily affects the small blood vessels in the white matter of the brain. CADASIL is characterized by migraine headaches and…

Dentinogenesis imperfecta type 2 is a rare and severe form of dentinogenesis imperfecta, a condition that affects tooth development. People affected by the condition may have weak and discolored teeth. These problems can affect both primary (baby) teeth and permanent teeth. People with this form of dentinogenesis imperfecta have no normal teeth. Sensorineural hearing loss…

Primary sclerosing cholangitis (PSC) is characterized by inflammation in the bile ducts (cholangitis) that leads to scarring (sclerosis), narrowing of the ducts, and a buildup of bile in the liver.[1] Early signs and symptoms include extreme tiredness, abdominal pain, and itchiness.[1] As the condition worsens it may cause jaundice, an enlarged spleen, and eventually liver…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 55880 Definition Chondrosarcoma is a malignant bone tumor arising from cartilaginous tissue, most frequently occuring at the ends of the femur and tibia, the proximal end of the humerus and the pelvis; and presenting with…

Post-transplant lymphoproliferative disease (PTLD) is a complication of transplantation in which there is uncontrolled growth of lymphocytes.[1][2] It occurs in people whose immune systems have been intentionally suppressed due to having a solid organ transplant or hematopoietic stem cell transplant.[1] The severity of PTLD can range from causing a mild, noncancerous (benign) overgrowth of tissue, to…

Shwachman-Diamond syndrome (SDS) affects many parts of the body, particularly the bone marrow, pancreas, and skeletal system. Symptoms include the inability to digest food due to missing digestive enzymes, low muscle tone, and anemia. Other symptoms include skeletal findings and intellectual disability. Children with SDS may have feeding difficulties, slow growth, and frequent infections. People with…

Hartnup disease is a metabolic disorder characterized by abnormal transport of certain amino acids in the kidney and gastrointestinal system. It is a type of aminoaciduria. The condition may be diagnosed based on the results of newborn screening tests. Most people with the condition have no symptoms (asymptomatic). For those who do show symptoms, the onset of…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 171436 Definition Typical nemaline myopathy is a moderate neonatal form of nemaline myopathy (NM; see this term) characterized by facial and skeletal muscle weakness and mild respiratory involvement. Epidemiology The annual incidence of NM has…

Acute lymphoblastic leukemia (ALL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell).[1] It may develop in children or adults. ALL spreads to the blood fairly quickly, and then may spread to other areas of the body such as the lymph nodes, liver, spleen, central…

Recurrent respiratory papillomatosis (RRP) is a rare viral disease where tumors (papillomas) grow in the air passages leading from the nose and mouth into the lungs (respiratory tract). There are two types, a juvenile-onset form and an adult-onset form. The tumors can cause a hoarse voice, chronic cough, and difficulty breathing. They may vary in…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 79434 Definition Oculocutaneous albinism type 1B (OCA1B) is a type of OCA1 (see this term) characterized by skin and hair hypopigmentation, nystagmus, reduced iris and retinal pigment and misrouting of the optic nerves. Epidemiology The…

Aplastic anemia is a blood disorder caused by failure of the bone marrow to make enough new blood cells. Bone marrow is a sponge-like tissue inside the bones that makes stem cells that develop into red blood cells, white blood cells, and platelets.[1] Symptoms may include fatigue, weakness, dizziness, shortness of breath, frequent infections, and bleeding….

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 29072 Definition Hereditary paraganglioma-pheochromocytomas (PGL/PCC) are rare neuroendocrine tumors represented by paragangliomas (occurring in any paraganglia from the skull base to the pelvic floor) and pheochromocytomas (adrenal medullary paragangliomas; see this term). Epidemiology Hereditary PGL/PCCs…

Antisynthetase syndrome is a chronic autoimmune condition that affects the muscles and various other parts of the body. The signs and symptoms can vary but may include muscle inflammation (myositis), polyarthritis (inflammation of many joints), interstitial lung disease, thickening and cracking of the hands, and Raynaud phenomenon. The exact underlying cause is unknown; however, the production of…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 3329 Definition Tibial aplasia-ectrodactyly syndrome is a rare condition characterized by congenital ectrodactylous limb malformations associated with tibial aplasia or hypoplasia. Epidemiology The incidence is estimated to be approximately 1 in 1,000,000 live births. Clinical…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 583 Definition Mucopolysaccharidosis type 6 (MPS 6) is a lysosomal storage disease with progressive multisystem involvement, associated with a deficiency of arylsulfatase B (ASB) leading to the accumulation of dermatan sulfate. Epidemiology Birth prevalence is…

Fragile XE syndrome (FRAXE) is a genetic condition associated with mild to borderline intellectual disabilities with physical features differing from person to person. The characteristic features are learning difficulties, often a consequence of communication problems (speech delay, poor writing skills), hyperactivity, and a shortened attention span. Nearly all cases of FRAXE are caused by a specific type of mutation, called a trinucleotide…

Pierre Robin sequence is a condition present at birth, in which the infant has a smaller than normal lower jaw (micrognathia), a tongue that is placed further back than normal (glossoptosis), and an opening in the roof of the mouth (cleft palate).[1][2] This combination of features can lead to difficulty breathing and problems with eating…

Pseudoxanthoma elasticum, PXE, is an inherited disorder that causes calcium and other minerals to accumulate in the elastic fibers of the skin, eyes, and blood vessels, and less frequently in other areas such as the digestive tract. PXE may cause the following symptoms: growth of yellowish bumps on the skin of the neck, under the arms,…

Type 1 plasminogen deficiency is a genetic condition associated with inflammed growths on the mucous membranes, the moist tissues that line body openings such as the eye, mouth, nasopharynx, trachea, and female genital tract. The growths may be triggered by local injury and/or infection and often recur after removal. The growths are caused by the deposition…

Localized scleroderma is characterized by thickening of the skin from excessive collagen deposits. Collagen is a protein normally present in our skin that provides structural support. However, when too much collagen is made, the skin becomes stiff and hard.[1] Localized types of scleroderma are those limited to the skin and related tissues and, in some…

Chronic recurrent multifocal osteomyelitis (CRMO) causes abnormal inflammation to occur in and around the bones. Symptoms usually begin in childhood but can occur at any age. Symptoms may include episodes of pain and joint swelling, skin redness, and sometimes a fever. In some cases, CRMO leads to abnormal bone growth, bone deformity, and fractures. Symptoms…

Niemann-Pick disease type B is an inherited condition involving lipid metabolism. People with this condition experience a build up of lipids in the spleen, liver, lungs, bone marrow, and brain.[1][2] Signs and symptoms typically develop in the pre-teen years and may include enlarged liver and spleen (hepatosplenomegaly), short stature, problems with lung function including frequent lung infections, and…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 143 Definition Parathyroid carcinoma (PRTC) is a very rare, slow-growing, clinically serious endocrine tumor that generally develops in mid-adulthood. PRTC presents as a palpable painless mass in the neck and causes severe hypercalcemia and related…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 1177 Definition Early onset cerebellar ataxia with retained reflexes (EOCARR) or Harding ataxia is a cerebellar ataxia characterized by the progressive association of a cerebellar and pyramidal syndrome with progressive cerebellar ataxia, brisk tendon reflexes,…

X-linked dominant chondrodysplasia punctata 2 (CDPX2), also known as Conradi-Hünermann-Happle syndrome, is a rare form of skeletal dysplasia characterized by skeletal malformations, skin abnormalities, cataracts and short stature. The specific symptoms and severity of the disorder may vary greatly from one individual to another. CDPX2 is caused by mutations in the emopamil binding protein gene, EBP….

Amyloidosis is a group of diseases in which a protein, called amyloid, builds up in the body’s organs and tissues. Amyloidosis AA is also referred to as Secondary amyloidosis or Inflammatory amyloidosis. This disease is caused by a long-lasting infection or inflammatory disease such as rheumatoid arthritis, familial Mediterranean fever, or osteomyelitis. Infection or inflammation in the body causes an increased amount…

Dystrophic epidermolysis bullosa (DEB) is one of the major forms of epidermolysis bullosa. The signs and symptoms can vary widely among affected people. In mild cases, blistering may primarily affect the hands, feet, knees, and elbows. Severe cases often involve widespread blistering that can lead to vision loss, disfigurement, and other serious medical problems. DEB…

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…

empty

Craniopharyngioma is a slow-growing, non-cancerous brain tumor that develops near the pituitary gland (a small endocrine gland at the base of the brain which produces several important hormones) and the hypothalamus (an endocrine organ which controls the release of hormones by the pituitary gland).[1][2][3] This tumor most commonly affects children between 5 and 10 years of age; however,…

Split hand foot malformation (SHFM) is a type of birth defect that consists of missing digits (fingers and/or toes), a deep cleft down the center of the hand or foot, and fusion of remaining digits.[1][2] The severity of this condition varies widely among affected individuals. SHFM is sometimes called ectrodactyly; however, this is a nonspecific term used to describe missing…

Familial partial lipodystrophy (FPLD) is a group of diseases characterized by an abnormal distribution of fat around the body. Specifically, fat is lost in the arms, legs, and hips, and gained around the face and liver. Symptoms usually develop around puberty and include problems breaking down food and resistance to the hormone that helps control…

Kallmann syndrome (KS) is a condition that causes hypogonadotropic hypogonadism (HH) and an impaired sense of smell. HH affects the production of the hormones needed for sexual development. It is present from birth and is due to deficiency of gonadotropin-releasing hormone (GnRH). KS is often diagnosed at puberty due to lack of sexual development. It…

Primary progressive aphasia (PPA) affects a person’s ability to use language to communicate. This includes difficulty making or understanding speech (aphasia).[1] PPA is a specific type of a more general disease called frontotemporal dementia.[2] PPA can be classified into three distinct types which include:[1] Progressive non-fluent aphasia (PNFA) Semantic dementia (SD) Logopenic progressive aphasia (LPA) PPA…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 545 Definition Follicular lymphoma is a form of non-Hodgkin lymphoma (see this term) characterized by a proliferation of B cells whose nodular structure of follicular architecture is preserved. Epidemiology Prevalence of follicular lymphoma is estimated…

Glioblastoma is a malignant (cancerous) brain tumor that develops from a specific type of brain cell called an astrocyte. These cells help support and nourish neurons (nerve cells of the brain) and form scar tissue that helps repair brain damage in response to injury. Glioblastomas are often very aggressive and grow into surrounding brain tissue. Signs…

Autosomal dominant optic atrophy plus syndrome (ADOA plus) is a rare syndrome that causes vision loss, hearing loss, and symptoms affecting the muscles. The syndrome is associated with degeneration of the optic nerve (optic atrophy). The optic nerve sends signals about what the eyes are seeing to the brain. When there is optic nerve damage,…

Axenfeld-Rieger syndrome is a group of disorders that mainly affects the development of the eye. Common eye symptoms include cornea defects and iris defects. People with this syndrome may have an off-center pupil (corectopia) or extra holes in the eyes that can look like multiple pupils (polycoria). About 50% of people with this syndrome develop glaucoma, a condition…

Bullous pemphigoid is a skin disorder characterized by large blisters. The blisters are usually located on the arms, legs, or middle of the body. In some people, the mouth or genitals are also affected.[1][2] The blisters may break open and form ulcers or open sores.[1] Bullous pemphigoid usually occurs in older persons and is rare…

empty

Chronic granulomatous disease (CGD) is a rare, inherited immunodeficiency that affects certain white blood cells. People with this condition have immune systems that do not function properly, leaving the body vulnerable to chronic inflammation and frequent bacterial and fungal infections. The features of this condition usually develop in infancy or early childhood; however, milder forms may…

Congenital lobar emphysema is a rare respiratory disorder in which air can enter the lungs but cannot escape, causing overinflation (hyperinflation) of the lobes of the lung. It is most often detected in newborns or young infants, but some cases do not become apparent until adulthood. Signs and symptoms may include difficulty breathing and respiratory distress…

X-linked ichthyosis is a disorder in which the skin cells are produced at a normal rate but they do not separate properly at the surface of the stratum corneum (the outermost layer of the skin). This slows the rate of shedding of the skin cells, resulting in a build-up of scales. The scales of X-linked…

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…

Huntington disease (HD) is an inherited condition that causes progressive degeneration of neurons in the brain. Signs and symptoms usually develop between ages 35 to 44 years and may include uncontrolled movements, loss of intellectual abilities, and various emotional and psychiatric problems. People with HD usually live for about 15 to 20 years after the condition begins….

Wolfram syndrome, which is also known by the acronym DIDMOAD, is an inherited condition characterized by diabetes insipidus (DI), childhood-onset diabetes mellitus (DM), a gradual loss of vision caused by optic atrophy (OA), and deafness (D).[1] Other symptoms may include bladder and bowel dysfunction, problems with the parts of the inner ear and brain that…

Acromegaly is a hormonal disorder that results from the pituitary gland producing too much growth hormone (GH). It is most often diagnosed in middle-aged adults, although symptoms can appear at any age. Signs and symptoms include abnormal growth and swelling of the hands and feet; bone changes that; alter various facial features; arthritis; carpal tunnel syndrome; enlargement of body organs; and…

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…

Duchenne muscular dystrophy (DMD) affects the muscles, leading to muscle wasting that gets worse over time. DMD occurs primarily in males, though in rare cases may affect females. The symptoms of DMD include progressive weakness and loss (atrophy) of both skeletal and heart muscle. Early signs may include delayed ability to sit, stand, or walk…

Nephrogenic diabetes insipidus is a disorder in which a defect in the small tubes (tubules) in the kidneys causes a person to produce a large amount of urine. Nephrogenic diabetes insipidus occurs when the kidney tubules, which allow water to be removed from the body or reabsorbed, do not respond to a chemical in the body called antidiuretic hormone (ADH)…

X-linked agammaglobulinema is a primary immunodeficiency characterized by very low levels of immunoglobulins (proteins made by the immune system to help fight infections). People affected by this condition generally begin developing frequent and recurrent bacterial infections from about 6 months of age. Commonly diagnosed infections include lung infections (pneumonia and bronchitis), middle ear infections, conjunctivitis,…

Zollinger-Ellison syndrome (ZES) is a condition in which tumors called gastrinomas in the pancreas and duodenum (part of the small intestine) cause high levels of the hormone gastrin in the blood. High levels of gastrin then cause production of too much stomach acid. Signs and symptoms may include abdominal pain, peptic ulcers, vomiting blood, and diarrhea.[1][2]…

Maternally inherited diabetes and deafness (MIDD) is a form of diabetes that is often accompanied by hearing loss, especially of high tones. The diabetes in MIDD is characterized by high blood sugar levels (hyperglycemia) resulting from a shortage of the hormone insulin, which regulates the amount of sugar in the blood. MIDD is caused by…

Hereditary elliptocytosis (HE) refers to a group of inherited blood conditions where the red blood cells are abnormally shaped. Symptoms vary from very mild to severe and can include fatigue, shortness of breath, gallstones, and yellowing of the skin and eyes (jaundice).[1][2] Some people with this condition have an enlarged spleen. Hereditary elliptocytosis is caused by a genetic change…

Barth syndrome is a metabolic and neuromuscular disorder, occurring almost exclusively in males, that primarily affects the heart, immune system, muscles, and growth. It typically becomes apparent during infancy or early childhood, but the age of onset, associated symptoms and findings, and disease course varies considerably among affected individuals. The main characteristics of the condition include abnormalities of…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 1576 Definition Infantile bilateral striatal necrosis (IBSN) comprises several syndromes of bilateral symmetric spongy degeneration of the caudate nucleaus, putamen and globus pallidus characterized by developmental regression, choreoathetosis and dystonia progressing to spastic quadriparesis. IBSN…

Myelodysplastic syndromes (MDS) are a group of blood disorders characterized by abnormal development of blood cells within the bone marrow. People with MDS have abnormally low blood cell levels (low blood counts). Signs and symptoms may include dizziness, fatigue, weakness, shortness of breath, bruising and bleeding, frequent infections, and headaches.[1][2] In some people with MDS, the…

Spina bifida is a type of neural tube defect in which the neural tube (the structure in an embryo that becomes the brain and spinal cord) does not completely close during development in the womb. This may result in part of the spinal cord sticking out through an opening in the spine, leading to permanent…

Pelizaeus-Merzbacher disease is a disorder that affects the brain and spinal cord. It is a type of leukodystrophy and is characterized by problems with coordination, motor skills, and learning. The age of onset and the severity of the symptoms varies greatly depending on the type of disease. It is caused by an inability to form…

Congenital hypothyroidism is a condition that affects infants from birth and results from a partial or complete loss of thyroid function (hypothyroidism). The thyroid gland makes hormones that play an important role in regulating growth, brain development, and metabolism in the body. Congenital hypothyroidism occurs when the thyroid gland fails to develop or function properly. In…

empty

Hereditary spherocytosis is a condition characterized by hemolytic anemia (when red blood cells are destroyed earlier than normal). Signs and symptoms can range from mild to severe and may include pale skin, fatigue, anemia, jaundice, gallstones, and/or enlargement of the spleen.[1] Other symptoms of hemolytic anemia may include feeling that your heart is pounding or racing (palpitations),…

Dandy-Walker complex is a group of disorders that affect the development of the brain. The changes in brain development are present from birth (congenital). Dandy-Walker complex affects the formation of the area of the brain known as the cerebellum, which is responsible for coordinating movement, and the fluid-filled spaces around it. People with Dandy-Walker complex…

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…

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…

Neurofibromatosis type 2 (NF2) is a disorder characterized by the growth of noncancerous tumors of the nervous system. Childhood symptoms include skin growths and eye findings. Almost all people with NF2 develop vestibular schwannomas affecting both ears by age 30. Other tumors of the central nervous system (the brain and spinal cord), skin and eye are also…

Multiple epiphyseal dysplasia (MED) is a group of disorders of cartilage and bone development, primarily affecting the ends of the long bones in the arms and legs (epiphyses). There are two types of MED, which are distinguished by their patterns of inheritance autosomal dominant and autosomal recessive. Signs and symptoms may include joint pain in…

Oculocutaneous albinism type 2 is a genetic condition that affects the coloring (pigmentation) of the skin, hair, and eyes. Affected individuals typically have very fair skin and white or light-colored hair. Long-term sun exposure greatly increases the risk of skin damage and skin cancers, including an aggressive form of skin cancer called melanoma, in people with…

Limb-girdle muscular dystrophy is a group of disorders which affect the voluntary muscles around the hips and shoulders. The conditions are progressive, leading to a loss of muscle strength and bulk over a number of years. Onset may occur in childhood, adolescence, young adulthood, or even later. Males and females are affected in equal numbers.[1] Most…

Argininosuccinic aciduria is an inherited disorder that causes ammonia to accumulate in the blood. Ammonia, which is formed when proteins are broken down in the body, is toxic if the levels become too high. The nervous system is especially sensitive to the effects of excess ammonia. Argininosuccinic aciduria usually becomes evident in the first few…

Hypereosinophilic syndrome (HES) refers to a rare group of conditions that are associated with persistent eosinophilia with evidence of organ involvement. Signs and symptoms vary significantly based on which parts of the body are affected. Although any organ system can be involved in HES, the heart, central nervous system, skin, and respiratory tract are the…

Multifocal motor neuropathy (MMN) causes damage to the nerves in the arms and legs. Nerve damage begins in adulthood and slowly gets worse over time. One side of the body may be more affected than the other. Symptoms of MMN may include weakness in the hands and lower arms; cramping; involuntary contractions or twitching; wrist…

Coffin-Lowry syndrome is a genetic condition that affects many parts of the body. The signs and symptoms and severity vary from person to person; however, males are typically more severely affected than females. Signs and symptoms may include distinct facial findings, short stature, microcephaly, kyphoscoliosis, other skeletal abnormalities, stimulus-induced drop episodes, intellectual disability and delayed development. Mutations…

Congenital dyserythropoietic anemia is a hereditary disease that affects the production of red blood cells (erythropoiesis) and is characterized by anemia and problems in various organs. The signs and symptoms may include fatigue, weakness, pale skin, yellowing of the skin and eyes (jaundice), larger-than-normal liver and spleen (hepatosplenomegaly), and problems of the heart.[1] There are…

Hypohidrotic ectodermal dysplasia (HED) is a genetic skin disease. Common symptoms include sparse scalp and body hair, reduced ability to sweat, and missing teeth. HED is caused by mutations in the EDA, EDAR, or EDARADD genes. It may be inherited in an X-linked recessive, autosomal recessive, or autosomal dominant manner depending on the genetic cause of the condition. The X-linked form is the…

Early-onset, autosomal dominant Alzheimer disease is a form of Alzheimer disease (AD) that develops before the age of 65. It is diagnosed in families that have more than one member with AD (usually multiple persons in more than one generation) in which the age of onset is consistently before age 60 and often between the ages…

Factor V deficiency is an inherited bleeding disorder that prevents blood clots from forming properly.[1] This disorder is caused by mutations in the F5 gene, which leads to a deficiency of a protein called coagulation factor V.[2] The reduced amount of factor V may lead to nosebleeds, easy bruising, and excessive bleeding following surgery or…

Optic atrophy 1, also known as optic atrophy type 1 is a disease that affects the optic nerve. The optic nerve carries signals from the eye to the brain about what is seen. People with optic atrophy type 1 have an optic nerve that has lost some tissue (atrophy). This atrophy causes the optic nerve…

Familial Mediterranean fever is an inherited condition characterized by recurrent episodes of painful inflammation in the abdomen, chest, or joints. These episodes are often accompanied by fever and sometimes a rash or headache. Occasionally inflammation may occur in other parts of the body, such as the heart; the membrane surrounding the brain and spinal cord;…

Idiopathic intracranial hypertension (IIH), formerly known as pseudotumor cerebri, is a condition that affects the brain. Pseudotumor cerebri literally translates to “false brain tumor.” This term was used because symptoms of IIH resemble those of brain tumors depsite no tumor being present. Symptoms of IIH may include severe headache, nausea and vomiting, altered vision, and pulsating…

Brugada syndrome is a heart condition that causes a disruption of the normal rhythm in the heart’s lower chambers (ventricular arrhythmia). Signs and symptoms usually develop in adulthood but the diagnosis may be made at any age.[1] Symptoms and complications often occur during rest or sleep, and may include fainting, seizures, difficulty breathing, or sudden…

Psoriatic juvenile idiopathic arthritis is a subtype of juvenile idiopathic arthritis that is characterized by both arthritis and psoriasis. Other signs and symptoms may include dactylitis (inflammation and swelling of an entire finger or toe); nail pitting or splitting; and eye problems. Although the underlying cause of psoriatic juvenile idiopathic arthritis is currently unknown (idiopathic),…

Smith-Magenis syndrome (SMS) is a developmental disorder that affects many parts of the body. The major features of this condition include mild to moderate intellectual disability, delayed speech and language skills, distinctive facial features, sleep disturbances, and behavioral problems. Most people with SMS have a deletion of genetic material in each cell from a specific region…

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disease characterized by weakness of the skeletal muscles. Common symptoms include weakness of the muscles that control the eye and eyelid, facial expressions, chewing, talking, and swallowing. Weakness tends to increase during periods of activity and improve after periods of rest. The condition results from a defect in…

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a neurological disorder that causes progressive weakness and impaired sensory function in the legs and arms. Symptoms often include tingling or numbness (first in the toes and fingers), weakness of the arms and legs, loss of deep tendon reflexes, fatigue, and abnormal sensations.[1] Other symptoms may include pain, difficulty…

Hypochondroplasia is a form of skeletal disease characterized by very short stature. Hypochondroplasia is similar to achondroplasia, but the features tend to be milder. People with hypochondroplasia usually have very short stature, large head, accentuated lordosis, short arms and legs, and broad, short hands and feet. Other features include a limited range of motion in…

ADNP syndrome, also known as Helsmoortel-van der Aa syndrome, is a complex neuro-developmental disorder that affects the brain and many other areas and functions of the body. ADNP syndrome can affect muscle tone, feeding, growth, hearing, vision, sleep, fine and gross motor skills, as well as the immune system, heart, endocrine system, and gastrointestinal tract.[1]…

Frontotemporal dementias (FTDs) are a group of neurodegenerative disorders associated with shrinking of the frontal and temporal anterior lobes of the brain.[1] Symptoms include marked changes in social behavior and personality, and/or problems with language. People with behavior changes may have disinhibition (with socially inappropriate behavior), apathy and loss of empathy, hyperorality (eating excessive amounts of…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 517 Definition A rare acute myeloid leukemia disorder characterized by increased blast cells (myeloblasts, monoblast, and/or promonoblasts), representing more than 20% of the total bone marrow (BM) or peripheral blood differential counts, with 20-80% of…

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs. Orpha Number: 79400 Definition Localized epidermolysis bullosa simplex, formerly known as EBS, Weber-Cockayne, is a basal subtype of epidermolysis bullosa simplex (EBS, see this term). The disease is characterized by blisters occurring mainly on the palms and…

Hereditary fructose intolerance (HFI) is a metabolic disease caused by the absence of an enzyme called aldolase B. In people with HFI, ingestion of fructose (fruit sugar) and sucrose (cane or beet sugar, table sugar) causes severe hypoglycemia (low blood sugar) and the build up of dangerous substances in the liver. HFI may be relatively mild or a…

Alpha mannosidosis  is a lysosomal storage disorder, a form of inborn metabolic disease. It is characterized by intellectual disability, hearing loss, ataxia, skeletal abnormalities, and coarse facial features.Signs and symptoms vary, but often include mild to moderate intellectual disability, hearing loss, weakened immune system, distinctive facial features, and cerebellar disorders (e.g., ataxia). Symptoms slowly worsen over time….

Sjogren-Larsson syndrome (SLS) is an inborn error of lipid metabolism, characterized by congenital ichthyosis (dry, scaly skin), intellectual disability, and spasticity (stiffness and involuntary muscle spasms). The syndrome is caused by mutations in the gene called FADH (fatty aldehyde dehydrogenase) and is inherited in an autosomal recessive fashion. Treatment is symptomatic.[1][2]

Pulmonary arterial hypertension (PAH) affects the heart and lungs. It is characterized by abnormally high blood pressure (hypertension) in the pulmonary artery, the blood vessel that carries blood from the heart to the lungs. Symptoms include shortness of breath (dyspnea) during exercise and fainting spells. The symptoms tend to get worse over time and may include dizziness, swelling…

Hereditary hemorrhagic telangiectasia (HHT) is an inherited disorder of the blood vessels that can cause excessive bleeding. People with HHT can develop abnormal blood vessels called arteriovenous malformations (AVMs) in several areas of the body. AVMs on the skin are called telangiectasias. AVMs can also develop in other parts of the body, including the brain, lungs,…

Tetrahydrobiopterin (BH4) deficiency causes the body to build up an abnormally high level of phenylalanine, one of the building blocks of proteins. In addition, BH4 deficiency leads to low levels of certain neurotransmitters, chemical messengers that control many body functions. Symptoms can range from very mild to severe. Babies with BH4 deficiency appear normal at birth…

Dermatitis herpetiformis is a rare, chronic, skin disorder characterized by groups of severely itchy blisters and raised skin lesions. These are more common on the knees, elbows, buttocks and shoulder blades. The slow onset of symptoms usually begins during adulthood, but children can also be affected. Other symptoms may include fluid-filled sores; red lesions that resemble hives;…