Adie's pupil is a type of pupil abnormality that is characterized by a sluggish or absent pupillary response to light. It is named after the Scottish neurologist William John Adie, who first described the condition in 1931. The condition is caused...

The term albinism typically refers to oculocutaneous (ok-u-low-ku-TAY-nee-us) albinism (OCA) — a group of inherited disorders where there is little or no production of the pigment melanin. The type and amount of melanin your body produces de...

Albinism is a rare, non-contagious, genetically inherited condition that results in little or no production of the pigment melanin in the skin, hair, and eyes. People with albinism may have very pale skin, white or light-colored hair, and vision p...

Bacterial keratitis is an infection of the cornea, the clear outer layer of the eye, caused by bacteria. Symptoms of bacterial keratitis include redness, pain, light sensitivity, blurred vision, and discharge from the eye. Treatment typically invo...

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...

Bloom syndrome is a rare genetic disorder characterized by short stature; increased sensitivity to light (photosensitivity); multiple small dilated blood vessels on the face (facial telangiectasia), often resembling a butterfly in shape; immune de...

Bloom syndrome is a rare genetic disorder characterized by short stature; increased sensitivity to light (photosensitivity); multiple small dilated blood vessels on the face (facial telangiectasia), often resembling a butterfly in shape; immune de...

Bulimia nervosa facts Bulimia is an eating disorder that is characterized by episodes of binging and purging the food and or associated calories. Bulimia is a significant public-health problem, both because of the physical...

Cataracts are a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Symptoms may include blurry vision, poor night vision, sensitivity to light and glare, faded colors, halos around lights, and double vision i...

Cockayne Syndrome (CS) is a rare form of dwarfism. It is an inherited disorder whose diagnosis depends on the presence of three signs (1) growth retardation, i.e. short stature, (2) abnormal sensitivity to light (photosensitivity), and (3) prematu...

Conjunctivitis, commonly known as pink eye, is an inflammation of the conjunctiva, the thin, transparent membrane that lines the inner surface of the eyelid and covers the white part of the eye. It is usually caused by a bacterial or viral infecti...

Contact lens-related eye infections are infections of the eye caused by the improper use of contact lenses. These infections can range from mild to severe and can cause a variety of symptoms, including redness, itching, burning, and blurred vision...

Corneal abrasion is a condition in which the outer layer of the cornea (the clear, dome-shaped surface that covers the front of the eye) is scratched or scraped. It is a common eye injury that can cause pain, redness, tearing, and light sensitivit...

Corneal dystrophies are a group of inherited eye disorders that cause progressive changes to the cornea, the clear outer layer of the eye. These disorders can cause vision loss and other eye problems. Symptoms vary depending on the type of corneal...

Corneal laceration is a tear or cut in the cornea, the clear, dome-shaped surface that covers the front of the eye. It is usually caused by a sharp object, such as a fingernail, a piece of metal, or a tree branch. Corneal lacerations can cause pai...

A corneal ulcer is an open sore on the cornea, the clear dome-shaped surface that covers the front of the eye. It is usually caused by an infection, such as bacterial, viral, or fungal, or by an injury to the eye. Symptoms of a corneal ulcer inclu...

Cyclic vomiting syndrome is characterized by episodes of severe vomiting that ha...

Cockayne Syndrome (CS) is a rare form of dwarfism. It is an inherited disorder whose diagnosis depends on the presence of three signs (1) growth retardation, i.e. short stature, (2) abnormal sensitivity to light (photosensitivity), and (3) prematu...

Depression is a mood disorder that causes a persistent feeling of sadness and loss of interest. Also called major depressive disorder or clinical depression, it affects how you feel, think and behave and can lead to a variety of emotional and phys...

Neuropathy is damage to nerves, and diabetic neuropathy is damage to nerves that occurs as a result of diabetes. Diabetes is thought to damage nerves as a result of prolonged elevated levels of blood glucose. Diabetic neuropathy can affect differe...

Familial dysautonomia is a rare genetic disorder of the autonomic nervous system (ANS) that primarily affects people of Eastern European Jewish heritage. It is characterized by diminished sensitivity to pain, lack of overflow tearing in the eyes, ...

Erythropoietic protoporphyria (EPP) is a rare inherited metabolic disorder characterized by a deficiency of the enzyme ferrochelatase (FECH). Due to abnormally low levels of this enzyme, excessive amounts of protoporphyrin accumulate in the bone m...

Erythropoietic protoporphyria (EPP) is a rare inherited metabolic disorder characterized by a deficiency of the enzyme ferrochelatase (FECH). Due to abnormally low levels of this enzyme, excessive amounts of protoporphyrin accumulate in the bone m...

General DiscussionCongenital rubella is a syndrome that occurs when a fetus has been infected with the rubella virus while in the uterus. It is primarily characterized by abnormalities of the heart and nervous system, the eyes and the ear...

Eye allergies, also known as allergic conjunctivitis, are a type of allergic reaction that affects the eyes. Symptoms of eye allergies include redness, itching, burning, tearing, and swelling of the eyes. Eye allergies are usually caused by airbor...

Fungal keratitis is an infection of the cornea, the clear outer layer of the eye, caused by a fungus. It is a rare but serious condition that can cause vision loss if not treated promptly. Symptoms of fungal keratitis include redness, pain, blurre...

Eosinophilic gastroenteritis is a rare digestive disease characterized by the triad of eosinophilic infiltration of segments of the gastrointestinal tract, abnormalities of gastrointestinal function (varying from dyspepsia and obstruction to diarr...

Hartnup disease is a rare metabolic disorder inherited as an autosomal recessive trait. It involves an inborn error of amino acid metabolism as well as niacin deficiency. Factors that may precipitate acute attacks of this disorder may include poor...

Hay-Wells syndrome, also known as ankyloblepharon-ectodermal dysplasia-clefting (AEC) syndrome, is a rare inherited disorder that belongs to a group of disorders known as the ectodermal dysplasias. Major characteristics of Hay-Wells syndrome inclu...

Familial dysautonomia is a rare genetic disorder of the autonomic nervous system (ANS) that primarily affects people of Eastern European Jewish heritage. It is characterized by diminished sensitivity to pain, lack of overflow tearing in the eyes, ...

Herpes Keratitis is an infection of the cornea caused by the herpes simplex virus (HSV). It is a common cause of corneal blindness and can cause severe vision loss if left untreated. Symptoms of Herpes Keratitis include redness, pain, light sensit...

Herpes Zoster, commonly known as shingles, is a viral infection caused by the varicella-zoster virus, the same virus that causes chickenpox. It is characterized by a painful rash with blisters that typically appears on one side of the face or body...

Adie Syndrome is a rare neurological disorder affecting the pupil of the eye. In most patients the pupil is dilated (larger than normal) and slow to react to light on nearby objects. In some patients, however, the pupil may be constricted (smaller...

Hyphema is a condition in which there is bleeding in the front chamber of the eye, between the cornea and the iris. It is usually caused by trauma to the eye, such as a blunt force or a sharp object. Symptoms of hyphema include blurred vision, red...

Juvenile Idiopathic Arthritis Uveitis (JIAU) is a type of eye inflammation that is associated with juvenile idiopathic arthritis (JIA). It is a rare condition that affects the uvea, which is the middle layer of the eye. Symptoms of JIAU include re...

Keratitis ichthyosis deafness (KID) syndrome is a rare, genetic, multi-system disorder. It is characterized by defects of the surface of the corneas (keratitis), red, rough thickened plaques of skin (erythrokeratoderma) and sensorineural deafness ...

Very long-chain acyl-CoA dehydrogenase deficiency (VLCAD) is a rare genetic disorder of fatty acid metabolism that is transmitted as an autosomal recessive trait. It occurs when an enzyme needed to break down certain very long-chain fatty acids is...

Marinesco-Sjogren syndrome (MSS) is a rare genetic disorder that affects multiple organ systems of the body. Common symptoms include difficulty coordinating voluntary movements due to degeneration (atrophy) of the cerebellum (cerebellar ataxia), c...

Migraine is a type of headache that is usually characterized by a throbbing or pulsing pain on one side of the head, accompanied by nausea, vomiting, and sensitivity to light and sound. It is a neurological disorder that affects about 12% of the p...

Migraine headache is a result of specific changes within the brain. It causes severe head pain that is often accompanied by sensitivity to light, sound, or smells. Common symptoms of migraine are: Eye pain Sensi...

Marinesco-Sjogren syndrome (MSS) is a rare genetic disorder that affects multiple organ systems of the body. Common symptoms include difficulty coordinating voluntary movements due to degeneration (atrophy) of the cerebellum (cerebellar ataxia), c...

Cockayne Syndrome (CS) is a rare form of dwarfism. It is an inherited disorder whose diagnosis depends on the presence of three signs (1) growth retardation, i.e. short stature, (2) abnormal sensitivity to light (photosensitivity), and (3) prematu...

Neonatal lupus is a rare autoimmune disorder that is present at birth (congenital). Affected infants often develop a characteristic red rash or skin eruption. In addition, infants with neonatal lupus may develop liver disease, a heart condition kn...

Nystagmus is a condition in which the eyes make repetitive, uncontrolled movements. It can be caused by a variety of conditions, including inner ear problems, vision problems, and neurological disorders. Symptoms may include blurred vision, dizzin...

Oculocutaneous albinism (OCA) is a group of rare inherited disorders characterized by a reduced amount or complete lack of melanin pigment in the skin, hair, and eyes. These conditions are caused by mutations in specific genes that are necessary f...

Onchocerciasis, also known as African River Blindness, is a parasitic infection caused by the filarial worm Onchocerca volvulus. It is transmitted to humans through the bite of an infected blackfly. Symptoms of the infection include severe itching...

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...

Photokeratitis is a painful eye condition caused by exposure to ultraviolet (UV) radiation. It is sometimes referred to as "snow blindness" or "welder's flash." Symptoms of photokeratitis include redness, tearing, pain, and temporary vision loss. ...

Phthisis, also known as pulmonary tuberculosis, is one of the most common illnesses that humans face. It affects people of all ages, from all walks of life, and in every country.  While phthisis may affect almost every organ in...

Cholinergic urticaria is a relatively common disorder of the immune system characterized by an immediate skin reaction (hypersensitivity) to heat, emotional stress, and/or exercise. Symptoms of the disorder include the appearance of distinctive sm...

Cholinergic urticaria is a relatively common disorder of the immune system characterized by an immediate skin reaction (hypersensitivity) to heat, emotional stress, and/or exercise. Symptoms of the disorder include the appearance of distinctive sm...

Familial dysautonomia is a rare genetic disorder of the autonomic nervous system (ANS) that primarily affects people of Eastern European Jewish heritage. It is characterized by diminished sensitivity to pain, lack of overflow tearing in the eyes, ...

Shingles is a medical condition that is caused by the reactivation of the chickenpox-causing virus in the body. Shingles are extremely painful but it isn’t life-threatening.  Shingles is a painful rash that occurs anywher...

Bloom syndrome is a rare genetic disorder characterized by short stature; increased sensitivity to light (photosensitivity); multiple small dilated blood vessels on the face (facial telangiectasia), often resembling a butterfly in shape; immune de...

Spinal headaches are a fairly common complication in those who undergo a spinal tap (lumbar puncture) or spinal anesthesia. Both procedures require a puncture of the membrane that surrounds the spinal cord and, in the lower spine, the lumbar and s...

Strabismus, commonly known as crossed eyes, is a condition in which the eyes are not properly aligned with each other. It is caused by a lack of coordination between the extraocular muscles, which control the movement of the eyes. Strabismus can c...

Reflex sympathetic dystrophy syndrome (RSDS), also known as complex regional pain syndrome, is a rare disorder of the sympathetic nervous system that is characterized by chronic, severe pain. The sympathetic nervous system is that part of the auto...

Cryptococcosis is caused by a fungus known as Cryptococcosis neoformans. The infection may be spread to humans through contact with pigeon droppings or unwashed raw fruit. Contact with an infected individual may also spread the infection. Individu...

Toxoplasmosis is an infection caused by the parasite Toxoplasma gondii. It is most commonly spread through contact with infected cat feces, but can also be spread through contaminated food or water, or from mother to baby during pregnancy. Symptom...

Trachoma is an infectious eye disease caused by the bacterium Chlamydia trachomatis. It is the leading cause of infectious blindness worldwide, and is most common in areas with poor hygiene and sanitation. Symptoms of trachoma include redness and ...

Trichiasis is a condition in which the eyelashes grow inwards, towards the eye, instead of outwards. This can cause irritation, pain, and even vision loss if left untreated. Treatment typically involves electrolysis or laser surgery to remove the ...

Porphyria cutanea tarda (PCT) is a type of porphyria in which affected individuals are sensitive to sunlight. Exposed skin shows abnormalities that range from slight fragility of the skin to persistent scarring and disfiguration. Due to fragility ...

Porphyria cutanea tarda (PCT) is a type of porphyria in which affected individuals are sensitive to sunlight. Exposed skin shows abnormalities that range from slight fragility of the skin to persistent scarring and disfiguration. Due to fragility ...

Physical urticaria is a condition in which red (erythematous) allergic skin lesions and itching (pruritus) are produced by exposure to heat, cold, or contact with chemicals or plants. These are called wheals by the medical community and may range ...

Uveitis is inflammation of the 'uvea' of the eye. The uvea is made up of three parts. The first part is the iris, which is the colored ring of tissue you can see in the mirror. The dark hole in the middle of the iris is the pupil. The second and t...

Uveitis is an inflammation of the uvea, the middle layer of the eye that contains the blood vessels, iris, and ciliary body. It can cause pain, redness, and blurred vision. Uveitis can be caused by infection, injury, or autoimmune diseases. Treatm...

Epidermolysis bullosa (EB) is a genetic skin disorder characterized clinically by blister formation from mechanical trauma. There are four main types with additional sub-types identified. There is a spectrum of severity, and within each type, one ...

De Sanctis-Cacchione syndrome is an extremely rare disorder characterized by the skin and eye symptoms of xeroderma pigmentosum (XP) occurring in association with neurological abnormalities, mental retardation, unusually short stature (dwarfism), ...