Osteopetrosis may be inherited as either a dominant or recessive trait and is marked by increased bone density, brittle bones, and, in some cases, skeletal abnormalities. Although symptoms may not initially be apparent in people with mild forms of...

Balo Disease is a rare and progressive variant of multiple sclerosis. It usually first appears in adulthood, but childhood cases have also been reported. While multiple sclerosis typically is a disease that waxes and wanes, Balo Disease is differe...

Bell's palsy (Bell palsy) is paralysis of the facial nerve of unknown cause. The diagnosis is made when no other cause can be identified. Although Bell's palsy is thought to be caused by a viral infection of the facial nerve, this hasn't been prov...

Parsonage-Turner syndrome is a relatively common condition characterized by inflammation of the network of nerves that control and supply (innervate) the muscles of the chest, shoulders, and arms (brachial plexus). Individuals with the condition f...

Parsonage-Turner syndrome is a relatively common condition characterized by inflammation of the network of nerves that control and supply (innervate) the muscles of the chest, shoulders, and arms (brachial plexus). Individuals with the condition f...

Brachial plexus palsy, also known as Erb's palsy, is a paralysis or weakness of the arm caused by an injury to one or more nerves that control and supply the muscles of the shoulder and upper extremities (upper brachial plexus). It is more commonl...

Cysticercosis (pork tapeworm infection) facts Cysticercosis is a parasitic disease caused by ingesting the eggs of the pork tapeworm, Taenia solium. Humans are infected by ingesting raw or undercooked pork, and cysticercos...

Locked-in syndrome is a rare neurological disorder in which there is complete paralysis of all voluntary muscles except for the ones that control the movements of the eyes. Individuals with locked-in syndrome are conscious and awake, but have no a...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

Brachial plexus palsy, also known as Erb's palsy, is a paralysis or weakness of the arm caused by an injury to one or more nerves that control and supply the muscles of the shoulder and upper extremities (upper brachial plexus). It is more commonl...

Japanese Encephalitis is a severe inflammation of the brain caused by the Japanese B Encephalitis Virus that is transmitted by the bite of infected mosquitoes in certain areas of the world, particularly Asia. This disorder most commonly affects ch...

Brachial plexus palsy, also known as Erb's palsy, is a paralysis or weakness of the arm caused by an injury to one or more nerves that control and supply the muscles of the shoulder and upper extremities (upper brachial plexus). It is more commonl...

Brachial plexus palsy, also known as Erb's palsy, is a paralysis or weakness of the arm caused by an injury to one or more nerves that control and supply the muscles of the shoulder and upper extremities (upper brachial plexus). It is more commonl...

Brachial plexus palsy, also known as Erb's palsy, is a paralysis or weakness of the arm caused by an injury to one or more nerves that control and supply the muscles of the shoulder and upper extremities (upper brachial plexus). It is more commonl...

Paramyotonia congenita is a rare muscular disorder inherited as an autosomal dominant trait. This nonprogressive disorder is characterized by a condition in which the muscles do not relax after contracting (myotonia). Symptoms can be triggered by ...

Familial idiopathic basal ganglia calcification (FIBGC) is a rare neurological disorder characterized by the presence of abnormal calcium deposits (calcifications) of unknown cause. Associated symptoms include progressive deterioration of cognitiv...

Familial idiopathic basal ganglia calcification (FIBGC) is a rare neurological disorder characterized by the presence of abnormal calcium deposits (calcifications) of unknown cause. Associated symptoms include progressive deterioration of cognitiv...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Metachromatic leukodystrophy, the most common form of leukodystrophy, is a rare inherited neurometabolic disorder affecting the white matter of the brain (leukoencephalopathy). It is characterized by the accumulation of a fatty substance known as ...

Guillain-Barre (gee-YAH-buh-RAY) syndrome is a rare disorder in which your body's immune system attacks your nerves. Weakness and tingling in your extremities are usually the first symptoms. These sensations can quickly spread, eventually ...

Epidermal nevus syndromes (ENSs) are a group of rare complex disorders characterized by the presence of skin lesions known as epidermal nevi associated with additional extra-cutaneous abnormalities, most often affecting the brain, eye and skeletal...

Parsonage-Turner syndrome is a relatively common condition characterized by inflammation of the network of nerves that control and supply (innervate) the muscles of the chest, shoulders, and arms (brachial plexus). Individuals with the condition f...

Japanese enenchephalitis is a viral infection that is transmitted through the bite of infected mosquitoes. It is a type of encephalitis, which is inflammation of the brain. Symptoms of Japanese encephalitis can include fever, headache, vomiting, c...

Machado-Joseph Disease (MJD-III), also called spinocerebellar ataxia type III, is a rare, inherited, ataxia (lack of muscular control) affecting the central nervous system and characterized by the slow degeneration of particular areas of the brain...

Kearns-Sayre syndrome (KSS) is a rare neuromuscular disorder characterized by three primary findings: progressive paralysis of certain eye muscles (chronic progressive external ophthalmoplegia [CPEO]); abnormal accumulation of colored (pigmented) ...

Kearns-Sayre syndrome (KSS) is a rare neuromuscular disorder characterized by three primary findings: progressive paralysis of certain eye muscles (chronic progressive external ophthalmoplegia [CPEO]); abnormal accumulation of colored (pigmented) ...

Kenny-Caffey syndrome type 2 (KCS2) is an extremely rare hereditary skeletal disorder characterized by thickening of the long bones, thin marrow cavities in the bones (medullary stenosis), and abnormalities affecting the head and eyes. Most cases ...

Kenny-Caffey syndrome type 2 (KCS2) is an extremely rare hereditary skeletal disorder characterized by thickening of the long bones, thin marrow cavities in the bones (medullary stenosis), and abnormalities affecting the head and eyes. Most cases ...

Epidermal nevus syndromes (ENSs) are a group of rare complex disorders characterized by the presence of skin lesions known as epidermal nevi associated with additional extra-cutaneous abnormalities, most often affecting the brain, eye and skeletal...

Epidermal nevus syndromes (ENSs) are a group of rare complex disorders characterized by the presence of skin lesions known as epidermal nevi associated with additional extra-cutaneous abnormalities, most often affecting the brain, eye and skeletal...

Osteopetrosis may be inherited as either a dominant or recessive trait and is marked by increased bone density, brittle bones, and, in some cases, skeletal abnormalities. Although symptoms may not initially be apparent in people with mild forms of...

Kearns-Sayre syndrome (KSS) is a rare neuromuscular disorder characterized by three primary findings: progressive paralysis of certain eye muscles (chronic progressive external ophthalmoplegia [CPEO]); abnormal accumulation of colored (pigmented) ...

Moebius syndrome is a rare neurological disorder characterized by weakness or paralysis (palsy) of multiple cranial nerves, most often the 6th (abducens) and 7th (facial) nerves. Other cranial nerves are sometimes affected. The disorder is present...

Moyamoya syndrome is a progressive disorder that affects the blood vessels in the brain (cerebrovascular). It is characterized by the narrowing (stenosis) and/or closing (occlusion) of the carotid artery inside the skull, the major artery that del...

Moyamoya syndrome is a progressive disorder that affects the blood vessels in the brain (cerebrovascular). It is characterized by the narrowing (stenosis) and/or closing (occlusion) of the carotid artery inside the skull, the major artery that del...

Narcolepsy is a chronic disease of the central nervous system. The symptoms include excessive daytime sleepiness (EDS), loss of muscle tone (cataplexy), distorted perceptions (hypnagogic hallucinations), inability to move or talk (sleep paralysis)...

Neuromyelitis optica, also known as Devic disease (DD), is a chronic disorder of nerve tissue characterized by inflammation of the optic nerve (optic neuritis) and inflammation of the spinal cord (myelitis). There appear to be two forms of this di...

Polio, short for poliomyelitis, is a highly contagious viral infection that can lead to paralysis, muscle weakness, and in severe cases, death. It primarily affects children under the age of 5. The virus is spread through contaminated food and wat...

Rabies is a viral disease that affects the central nervous system of mammals, including humans. It is usually transmitted through the bite of an infected animal, such as a dog, bat, raccoon, or fox. Rabies is a serious and often fatal disease if n...

Ramsay Hunt syndrome (RHS) is a rare neurological disorder characterized by paralysis of the facial nerve (facial palsy) and a rash affecting the ear or mouth. Ear abnormalities such as ringing in the ears (tinnitus) and hearing loss may also be p...

Japanese Encephalitis is a severe inflammation of the brain caused by the Japanese B Encephalitis Virus that is transmitted by the bite of infected mosquitoes in certain areas of the world, particularly Asia. This disorder most commonly affects ch...

Tolosa-Hunt syndrome is a rare disorder characterized by severe periorbital headaches, along with decreased and painful eye movements (ophthalmoplegia). Symptoms usually affect only one eye (unilateral). In most cases, affected individuals experie...

C syndrome, also known as Opitz trigonocephaly syndrome, is a rare disorder transmitted as a result of "gonadal mosaicism". Mosaicism refers to a condition in which a person has cells that differ from each other in genetic makeup. The difference i...

Brachial plexus palsy, also known as Erb's palsy, is a paralysis or weakness of the arm caused by an injury to one or more nerves that control and supply the muscles of the shoulder and upper extremities (upper brachial plexus). It is more commonl...

VACTERL association is a nonrandom association of birth defects that affects multiple median and para-median structures. The term VACTERL is an acronym with each letter representing the first letter of one of the more common findings seen in affec...