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All Communities

  • Aagenaes Syndrome

    5 members

    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

    1 members

    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

    6 members

    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

    5 members

    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...

  • Absent Pulmonary Valve Syndrome

    4 members

    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...

  • Acalvaria

    4 members

    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

    28 members

    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

    1 members

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

  • Aceruloplasminemia

    2 members

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

  • Achalasia

    18 members

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

  • Acheiropodia

    1 members

    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

    9 members

    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

    1 members

    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

    5 members

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

  • Acquired Hemophilia

    2 members

    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


    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

    4 members

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

  • Acrofacial Dysostosis, Rodriguez Type

    3 members

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

  • Acromegaly

    23 members

    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

    10 members

    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

    12 members

    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

    1 members

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



  • Acute Lymphoblastic Leukemia

    5 members

    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

    1 members

    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

    4 members

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


  • Acute Retinal Necrosis

    2 members

    Acute Retinal Necrosis is a rare type of inflammation of the retina in the eye.

  • Acute Zonal Occult Outer Retinopathy

    2 members

    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


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

  • Adams-Oliver Syndrome

    2 members

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

  • Addison's Disease

    55 members

    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

    3 members

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

  • Adenoid Cystic Cancer

    2 members

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

  • Adie Syndrome

    1 members

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

  • Adiposis Dolorosa

    16 members

    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

    3 members

    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

    67 members

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

  • Adrenomyeloneuropathy

    296 members

    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

    6 members

    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

    3 members

    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

    3 members

    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

    48 members

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

  • Alexander Disease

    7 members

    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

    5 members

    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

    7 members

    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

    4 members

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

  • Alpha-1 Antitrypsin Deficiency

    13 members

    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

    3 members

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

  • Alpha-Sarcoglycanopathy


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

  • Alport Syndrome

    3 members

    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...

  • Alström Syndrome

    1 members

    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

    2 members

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

  • Ameloblastoma

    5 members

    Ameloblastoma is a rare, benign tumor of the mouth.

  • Amelogenesis Imperfecta, Nephrocalcinosis

    9 members

    Amelogenesis Imperfecta, Nephrocalcinosis, is an enamel-renal disorder, where one develops abnormal formation of teeth enamel and also nephrocalcinosis.


  • Amniotic Band Syndrome

    3 members

    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

    11 members

    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), Lou Gehrig's Disease

    12 members

    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 Carcinoma

    3 members

    Anaplastic Thyroid Cancer is a form of thyroid cancer.

  • Ancylostomiasis

    2 members

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

  • Andersen Tawil Syndrome

    11 members

    Andersen Tawil Syndrome is a type of Periodic Paralysis that presents with episodic weakness including paralysis and cardiac abnormalities which can include Long QTS 7 in some, but not all patients.

  • Androgen Insensitivity Syndrome

    5 members

    Androgen Insensitivity Syndrome is a rare genetic disorder caused by mutations of the gene encoding the androgen receptor.

  • Anencephaly


    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

    10 members

    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

    20 members

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

  • Angiomyomatous Hamartoma

    3 members

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

  • Angiosarcoma

    1 members

    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

    2 members

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

  • Ankylosing Spondylitis

    16 members

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

  • Anophthalmia - Syndactyly Syndrome

    4 members

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

  • Anorchism

    2 members

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

  • Anti-MAG Peripheral Neuropathy

    3 members

    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

    10 members

    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

    207 members

    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

    2 members

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

  • Apert Syndrome

    1 members

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

  • Aplastic Anemia

    7 members

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

  • Appendix Cancer

    4 members

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

  • Aquagenic Pruritus

    8 members

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

  • Arachnoid Cyst

    5 members

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

  • Arachnoiditis

    12 members

    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)

    1 members

    Arthrogryposis-renal dysfunction-cholestasis (ARC) syndrome is a rare but fatal autosomal recessive multisystem disorder caused by mutations in the VPS33B or VIPAR gene

  • Arnold-Chiari Malformation

    36 members

    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

    2 members

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

  • Arteriovenous Malformation

    10 members

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

  • Arthritis-Related Enthesitis

    13 members

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

  • Arthrogryposis Multiplex Congenita

    7 members

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

  • Askin's Tumor

    12 members

    Askin's Tumor is a rare type of cancer characterized by the development of tumors in bone or soft tissue.

  • Aspartylglucosaminuria

    3 members

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

  • Asperger Syndrome

    12 members

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

  • Associative Agnosia

    2 members

    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

    8 members

    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

    1 members

    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

    7 members

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

  • Atypical Hemolytic Uremic Syndrome

    1 members

    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

    8 members

    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

    31 members

    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

    4 members

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

  • Autoimmune Polyendocrine Syndrome, Type 2

    7 members

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

  • Autoimmune Polyendocrinopathy Syndrome Type 1

    5 members

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

  • Autoimmune Progesterone Dermatitis

    13 members

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

  • Autosomal dominant tubulointerstitial kidney disease

    1 members


    Description from GARD,

    Autosomal dominant tubulointersti...

  • Autosomal Recessive Cerebellar Ataxia Type 1

    1 members

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

  • Autosomal Recessive Polycystic Kidney Disease

    5 members

    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 (MCPH)

    8 members

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

  • Avascular Necrosis

    5 members

    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...

  • Axenfeld-Rieger Syndrome

    22 members

    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...