Aagenaes syndrome, also known as lymphedema-cholestasis syndrome (LCS), is a rare genetic disease affecting the liver and is characterized by a reduced size and number of the lymph ves...

Aarskog-Scott syndrome is a rare disease that results in developmental abnormalities in the body, such as shortened stature, abnormal facial features, and limb and genital abnormalities. This ra...

Aase syndrome is a rare disease usually diagnosed at birth from physical features that are characteristic of this disease. These include abnormal build-up of cerebrospinal fluid (CSF) ...

Abetalipoproteinemia is a rare disease that lowers the body’s ability to absorb fats from food in the intestine and mobilize it in the liver. The disease is caused by a lack of f...

The human heart is composed of four chambers: the left and right atria on top and the left and right ventricles below. Blood from the body enters the right ventricle and is then pumped through t...

The human skull consists of a number of bones that have fused together. Among these bones are the frontal bone which makes up the forehead, the temporal bones, and parietal bones which make up t...

Acanthamoeba Keratitis (AK) is a rare infection in the cornea of the eye. The cornea is a transparent layer that covers the front of the eye. A condition in which the cornea becomes inflamed is ...

Acatalasemia a genetic deficiency of erythrocyte catalase characterized by infection of the gums.

Aceruloplasminemia is a rare iron metabolism disorder characterized by progressive neurodegeneration of the retina and basal ganglia, and diabetes mellitus.

Achalasia is a rare disorder affecting the lower esophageal sphincter characterized by difficulty in swallowing (dysphagia) and regurgitation of undigested food.

Acheiropodia is an extremely rare genetic disorder characterized by an impaired development of the upper and lower extremities. People who suffer from acheiropodia are born without hands and fee...

Achondroplasia is the most frequent type of short limb dwarfism. It is a disorder that prevents the changing of cartilage to bone, leading to short arms and legs, limited range of elbow motion, ...

Ackerman syndrome, or Ackerman fused molar roots syndrome, is a rare disease that causes fused molar roots to develop along with other teeth and mouth abnormalities. This is a congenit...

Acoustic neuroma is a benign tumor that forms on the vestibulocochlear nerve leading from the brain to the inner ear.

Acquired hemophilia (AH) is an autoimmune disorder that affects the normal functioning of coagulation factors and prevents the blood from clotting. An autoimmune disease describes when the body&...

Acrodermatitis enteropathica is a metabolic disorder due to zinc insufficiency. Zinc is a trace element that is required for the correct function of many proteins in the body. When zinc is missi...

Acrodysostosis is a rare congenital disorder characterized by problems in the bones of the hands, feet, and nose, and mental retardation.

Acrofacial Dysostosis is a group of disorders characterized by defective limb and facial development.

Acromegaly - also known as Growth Hormone-Secreting Pituitary Adenoma, Growth Hormone Excess, Somatotropic Adenoma, Somatotroph Adenoma, Somatotrophinoma, and Giant Pituitary⁶ - is a ...

Acute disseminated encephalomyelitis (ADEM) is a rare disease caused by inflammation in the brain and spinal cord that breaks down myelin and damages nerve cells and nerve impulses. To...

Acute Hepatic Porphyria (AHP) is a group of rare genetic conditions characterized by an enzyme deficiency in the liver. The different subtypes of AHP from the most common to the least common are...

Acute Interstitial Pneumonia is a rare lung disease which usually affects otherwise healthy individuals.

Acute lymphoblastic leukemia is a cancer that begins in the bone marrow, which instead of producing healthy white blood cells will instead produce a high volume of transitional cells c...

Acute Myelogenous Leukemia is a stem cell cancer that effects the bone marrow or can manifest in the skin as lukemia cutis or in the brain. But is mainly a sistemic disease of the blood system and ...

Acute Promyelocytic Leukemia is a subtype of acute myelogenous leukemia, a cancer of the blood and bone marrow.

Acute retinal necrosis (ARN) is an infection in the eye causing inflammation in the retina, a layer of cells at the back of the eye that absorb light and send signals to the brain. The retina is...

Acute Zonal Occult Outer Retinopathy is a rare eye disorder in which the retina becomes inflamed, resulting in loss of vision which is typically temporary, lasting several years.

Adactylia Unilateral Dominant is a rare genetic condition characterized by missing portions of fingers.

Adams-Oliver Syndrome is a rare disorder resulting in defects of the scalp and cranium as well as with limb malformations.

Addison´s disease is a rare endocrine or hormonal disorder characterized by a diminished production of hormones by the adrenal glands. The adrenal gl...

Adenine Phosphoribosyltransferase Deficiency is a rare genetic disorder that may cause kidney stones and possibly kidney failure.

Adenoid Cystic Cancer is a rare form of cancer that can exist in many different areas of the body.

Adie Syndrome is a neurological disorder which affects the pupil of the eye and the autonomic nervous system.

Adiposis dolorosa is a rare disorder affecting fatty tissue under the skin. Affected individuals present with fatty growths, known as lipoma, found most commonly on the torso, upper parts of the...

Adrenocortical carcinoma is a rare disease stemming from the formation of  cancerous tumors  in the outer layer of the adrenal gland, also called the adrenal cortex. In human...

Adrenoleukodystrophy is a rare disease characterized by progressive brain damage and failure of the adrenal glands.

Adrenomyeloneuropathy (AMN) is an inherited condition caused by a genetic mutation impairing the ability to metabolize very long-chain fatty acids (VLCFAs). Fatty acids are the buildin...

Adult Onset Still's Disease is a rare form of rheumatoid arthritis that occurs in adults and attacks internal organs, joints and other parts of the body.

Aicardi Syndrome is a rare genetic syndrome characterized by the partial or complete absence of the corpus callosum (the corpus callosum is the part of the brain which allows the right side to comm...

Alagille syndrome is a rare disorder present from birth that can affect many different organs of the body. The major organs affected include the liver, heart, spine, and eye. 

Albright hereditary osteodystrophy (AHO) is a genetic, metabolic disorder, characterized by brachydactyly (shortening of the fingers), subcutaneous calcifi...

Alexander disease is a rare disorder affecting the nervous system. It is a condition characterized by the destruction of the myelin sheath and what is called Rosenthal fibers. The myel...

Alkaptonuria is a rare genetic metabolic disease, characterized by the accumulation of acid in various tissues. Those affected by the disease do not have an enzyme that can break down homogentis...

Alopecia Totalis (AT) is a condition characterized by the complete loss of hair on the scalp. It is considered to be an advanced form of Alopecia Areata (AA), a condition resulting in round patc...

Alpers Syndrome is a rare degenerative disease affecting the central nervous system that occurs primarily in infants and children.

Alpha-1 Antitrypsin Deficiency is a rare genetic disorder caused by damaged alpha 1-antitrypsin proteins whose purpose is to keep neutrophil elastase enzymes in check.

Alpha-Mannosidosis is a lysosomal storage disorder caused by deficient activity of the alpha-D-mannosidase enzyme.

Alpha-Sarcoglycanopathy is rare genetic disorder involving progressive muscle weakness of the pelvic and shoulder muscles.

Alport Syndrome is a progressive genetic disorder that affects kidney function and causes abnormalities of the inner ear and eye. There are 3 forms of Alpo...

Alstrom Syndrome is a very rare recessive disorder causing childhood blindness, hearing loss, obesity, heart failure, kidney failure, diabetes and many related disorders.

Alternating hemiplegia of childhood (AHC) is a rare neurological disorder often caused by a mutation in ATP1A3,

Ameloblastoma is a rare, benign tumor of the mouth.

Amelogenesis Imperfecta (AI) is a group of rare disorders affecting the development of tooth enamel, either causing problems in its development or a lack of development completely. Too...

Amniotic band syndrome is a congenital syndrome. The associated symptoms of this syndrome are highly variable. There are different causes of amniotic band syndrome. An affected baby is born with...

Amyloidosis is a rare disorder characterized by the aggregation of abnormally formed or folded proteins in different organs, systems, or tissues. Amyloid refers to a protein that is necessary fo...

Amyotrophic Lateral Sclerosis (ALS) is a progressive rare neurological disease that involves the degeneration of nerve cells and motor neurons, causing the loss of control over voluntary muscles...

Anaplastic Thyroid Cancer is a form of thyroid cancer.

Ancylostomiasis-- also known as hookworm infection, is a rare parasitic disease caused by the Ancylostoma hookworms.  Infection occurs when a worm larvae enters...

Anderson-Tawil Syndrome (ATS) is a rare genetic disorder characterized by a triad of features: periodic paralysis, cardiac arrhythmias, and distinct physical anomalies. The syndrome is...

Anencephaly is a rare disorder caused by the neural tube failing to close resulting in the absence of a major portion of the brain, skull, and scalp.

Angelman syndrome is a genetic disorder caused by deletion of genes on chromosome 15 and is typically characterized by developmental delay, sleep disturbance, seizures, jerky movements, and frequen...

Angioedema is a rare disorder characterized by rapid swelling of the dermis, subcutaneous tissue, mucosa and submucosal tissues.

Angiomyomatous Hamartoma is a rare type of tumor occurring in lymph nodes in the inguinal area of the body.

This is a community for Angiosarcoma Cancer. Of the 1.75 million new cases of cancer in the United States, there are about 3 cases per year. This community is open to Doctors, patients and loved...

Aniridia is a rare disorder characterized by the underdevelopment of the iris.

Ankylosing Spondylitis is a chronic, painful, degenerative inflammatory arthritis primarily affecting spine and sacroiliac joints.

Anophthalmia-syndactyly syndrome, also known as microphthalmia with limb anomalies or ophthalmoacromelic syndrome, is a rare disorder that results in malformations o...

Anorchism is a rare condition resulting in the absence of the testes.

Anti-MAG Peripheral Neuropathy is a rare disorder in which a person’s own immune system attacks cells that maintain a healthy nervous system.

Antiphospholipid syndrome (APS), also known as antiphospholipid antibody syndrome or Hughes syndrome, is a rare autoimmune disorder in which there are recurring epis...

Antisynthetase syndrome is a rare, chronic, inflammatory autoimmune disorder that affects the muscles and other parts of the body. An autoimmune disorder is one where the body’s own immune...

Aortic Valve Stenosis is a heart disorder caused by the incomplete opening of the aortic valve.

Apert Syndrome is a congenital disorder affecting the first branchial arch.

Aplastic Anemia is a disorder where the bone marrow does not produce sufficient blood cells.

Appendix Cancer is a rare form of cancer with the most common types being carcinoid tumor and adenocarcinoma.

Aquagenic Pruritus is a rare skin disorder characterized by intense itching after contact with water.

Arachnoid Cysts are fluid-filled sacs that are located between the brain or spinal cord and the arachnoid membrane.

Arachnoiditis is a rare neuropathic disease caused by the inflammation of one of the membranes that surrounds the nerves of the central nervous system.

ARC Syndrome (Arthrogryposis-Renal Dysfunction-Cholestasis) is a rare, autosomal recessive genetic disorder characterized by limited mobility of the joints called congenital joint cont...

Arnold Chiari malformations (CM) are structural abnormalities at the base of the skull where the brain and spinal cord meet. It is a congenital or acquired...

Arrhythmogenic right ventricular dysplasia is a type of nonischemic cardiomyopathy that involves primarily the right ventricle

Arteriovenous Malformation is a disorder that affects the connections between veins and arteries disallowing the delivery of nutrients to tissue.

Arthritis-Related Enthesitis is inflammation of the site at which the tendon or ligament attaches to the bone due to arthritis.

Arthrogryposis Multiplex Congenita is a rare, non-progressive, congenital disorder characterized by multiple joint contractures, including muscle weakness and fibrosis.

Ewing Family of Tumors refers to a group of tumors that have similar genetic causes that lead to tumor development in bones and soft tissues. Ewing Family of Tumors includes four subty...

Aspartylglucosaminuria is a rare lysosomal storage disorder caused by an enzyme N-aspartyl-beta-glucosaminidase (aspartylglucosaminidase) deficiency.

Asperger Syndrome is characterized by difficulties in social interaction and restricted patterns of behavior and interests.

Associative Agnosia is a rare disorder characterized by the loss of the ability to assign meaning to an object, animal or building that the patient can see clearly.

Ataxia telangiectasia (AT)is a rare genetic disease that is characterized by progressive impairment of voluntary movement coordination (ataxia), formation of thread-like red patterns o...

Atelosteogenesis type 1 is a rare skeletal disorder that affects the development of bones throughout the body. Certain bones may be underdeveloped or absent includin...

Atrial Fibrillation is an abnormal heart rhythm involving the two upper chambers of the heart.

Hemolytic Uremic Syndromes (HUS) are a group of conditions characterized by low red blood cells, low platelets, and kidney damage and inflammation. As a re...

Atypical Odontalgia is a rare dental disorder characterized by a continuous severe aching tooth, usually occurring in a molar or in a tooth next to a molar.

Autism Spectrum Disorder (ASD) is a developmental disorder that causes brain differences that impact communication and social behavior. Symptoms generally develop in the first 2-3 years of ...

Autoimmune hypophysitis is a rare disorder causing inflammation of the pituitary gland.

Autoimmune Polyendocrine Syndrome, Type 2 is a rare autoimmune disorder characterized by Addison's disease, hypothyroidism and diabetes mellitus.

Autoimmune Polyendocrinopathy Syndrome Type 1 is a rare autoimmune disorder characterized by autoimmune polyendocrinopathy, candidiasis and ectodermal dysplasia.

Autoimmune Progesterone Dermatitis is a rare skin rash that affected women.

Description from GARD, https://rarediseases.info.nih.gov/diseases/10801/medullary-cystic-kidney-disease

Autosomal dominant tubulointersti...

Autosomal Recessive Cerebellar Ataxia Type 1 is a rare, progressive neurological disorder primarily affecting individual from Quebec, Canada.

Autosomal recessive polycystic kidney disease or ARPKD is a rare genetic disease characterized by the development of cysts (sacs full of fluid) in both kidneys that can eventually lead to kidney...

Autosomal recessive primary microcephaly (often shortened to MCPH, which stands for "microcephaly primary hereditary") is a condition in which in...

Avascular Necrosis (AVN) also known as Osteonecrosis, is a condition resulting in the death of bone cells. Namely, when the blood flow to bone cells is greatly reduced, cells can die and this ca...

The human eye is anatomically complex, consisting of many different parts and layers that work together to produce a clear vision. The cornea, a transparent layer at the front of the e...