Glossary of Rare Conditions

Ankylosing spondylitis
Bartonella
Behçet’s disease
Birdshot retinopathy
Blepharitis
Candida
Chronic cyclitis
Coccidioidomycosis
Corneal dystrophy
Corneal infections
Crohn's disease
Cryptococcosis
Fuchs' dystrophy
Fungal keratitis
Granular corneal dystrophy type I
Granular corneal dystrophy type II
Herpes simplex keratitis
Herpes zoster (shingles)
Juvenile rheumatoid arthritis associated with iridocyclitis
Keratoconus
Lattice dystrophy
Lens-induced uveitis
Leprosy
Leptospirosis
Lyme disease
Lymphoma of the eye
Map-dot-fingerprint dystrophy
Ocular surface neoplasia (tumor)
Polycythemia vera
Posterior polymorphous corneal dystrophy
Psoriatic arthritis
Reactive arthritis
Sarcoidosis
Squamous cell carcinoma of the eyelid
Stevens-Johnson syndrome
Sympathetic ophthalmia
Syphilis
Toxocariasis
Toxoplasmosis
Tuberculosis of the eye
Ulcerative colitis
Vogt-Koyanagi-Harada syndrome
Whipple's disease

Ankylosing spondylitis: (pronounced ank-kih-low-sing spon-dill-eye-tiss), or AS, is a form of arthritis that primarily affects the spine, although other joints can become involved. It causes inflammation of the spinal joints (vertebrae) that can lead to severe, chronic pain and discomfort. In the most advanced cases (but not in all cases), this inflammation can lead to new bone formation on the spine, causing the spine to fuse in a fixed, immobile position, sometimes creating a forward-stooped posture. This forward curvature of the spine is called kyphosis. AS can also cause inflammation, pain and stiffness in other areas of the body such as the shoulders, hips, ribs, heels, and small joints of the hands and feet. Sometimes the eyes can become involved (known as Iritis or Uveitis), and rarely, the lungs and heart can be affected. Courtesy of the Spondylitis Association of America.

Bartonella: Bacteria that live inside cells that can infect humans, mammals and a wide range of wild animals. Not all Bartonella species cause disease in humans. Bartonella henselae causes an important emerging infection first reported in 1990 and described as a new species in 1992. It is mainly carried by cats and causes cat-scratch disease, endocarditis, and several other serious diseases in humans. Read more.

Behçet’s disease: Rare in the U.S., but common in the Middle East, Asia and Japan. In Middle Eastern and Asian countries, the disease affects more men than women. In the U.S., it affects more women than men. Behcet's disease tends to develop in people in their 20’s or 30's, but people of all ages can develop this disease. Behcet's Disease is an autoimmune disease that results from damage to blood vessels throughout the body, particularly veins. In an autoimmune disease, the immune system attacks and harms the bodies' own tissues. The exact cause of Behcet's Disease is unknown. Read more.

Birdshot retinopathy: An uncommon chronic posterior uveitis characterized by vitritis and multiple ovoid spots, which are orange to cream in color and hypopigmented. These spots are mainly distributed in the posterior pole and in the mid periphery of the retina. The classic presentation is described to "resemble the pattern seen with birdshot in the scatter from a shotgun." Read more.

Blepharitis: This is a common and ongoing condition where the eyelids become inflamed (swollen) with oily particles and bacteria coating the eyelid margin near the base of the eyelashes. Read more.

Candida: A yeast microorganism that commonly lives in the intestinal tract of every human being. It shares space in your bowel with a variety of other microorganisms, mostly helpful bacteria, called probiotics. The bacteria-to-yeast ratio in a healthy person is about 10:1, so in a normal bowel everything lives in a nice ecological balance. The problem comes when your “inner ecology” gets off balance through a variety of causes. The bowel becomes vulnerable to other opportunistic’ microorganisms seeking a new home. With no healthy probiotics to keep it under control, the growth of yeast takes off, multiplies and causes Candida Overgrowth yeast infection resulting in a multitude of symptoms.

Chronic cyclitis: A clinical condition characterized by chronic low-grade inflammation of the anterior segment, anterior vitreous and peripheral retina. The predominant cellular reaction is seen in the vitreous. A peripheral membrane is usually present. It is sometimes accompanied by posterior pole edema, including disc edema and macular edema. This condition usually begins with blurred vision or floaters, or it may be asymptomatic and be discovered during a routine examination.

Coccidioidomycosis: An infection caused by the fungus Coccidioides, also called valley fever. The fungus is known to live in the soil in the southwestern United States and parts of Mexico and Central and South America. The fungus was also recently found in south-central Washington. People can get valley fever by breathing in the microscopic fungal spores from the air, although most people who breathe in the spores don’t get sick. Usually, people who get sick with valley fever will get better on their own within weeks to months, but some people will need antifungal medication. Read more.

Corneal dystrophy: A corneal dystrophy is a condition in which one or more parts of the cornea lose their normal clarity due to a buildup of cloudy material. There are over 20 corneal dystrophies that affect all parts of the cornea. Read more.

Corneal infections: Sometimes the cornea is damaged after a foreign object has entered the tissue, such as from a poke in the eye. At other times, bacteria, parasites or fungi from a contaminated contact lens can pass into the cornea.

Crohn’s disease: Approximately 10% of people with inflammatory bowel disease experience eye problems. Most of these are treatable and do not pose any significant threat as far as loss of vision is concerned. Still, if you notice any type of eye irritation or inflammation, bring it to your doctor’s attention sooner rather than later. Read more.

Cryptococcosis: An infection caused by Cryptococcus neoformans fungus, which is usually found in soil. If you breathe it in, it infects your lungs. The infection may go away on its own, remain in the lungs only, or spread throughout the body (disseminate). This infection is most often seen in people with a weakened immune system, such as those with HIV infection, taking high doses of corticosteroid medications, cancer chemotherapy, or who have Hodgkin's disease. Cryptococcus is one of the most common life-threatening fungal infections in people with AIDS. Read more.

Fuchs' dystrophy: A progressive disease affecting the cornea. Fuchs' dystrophy reduces the number of specific cells (called endothelial cells) that make up the inner layer of the cornea. Endothelial cells are key to processing water that makes up the corneal cell structure. When the endothelial cells diminish, the cells stop processing water properly and fluid starts to build up. The corneal tissue gradually thickens, causing the cornea to become swollen and cloudy, losing its crystal-clear transparency. Read more.

Fungal keratitis: An infection of the cornea that causes pain, reduced vision, light sensitivity and tearing or discharge from your eye. Resulting from infection from contact lens use or injury to the eye, fungal keratitis usually develops very quickly, and if left untreated, can cause blindness. The fungus usually responsible for this type of keratitis infection is Fusarium. Read more.

Granular corneal dystrophy type I: This form of corneal dystrophy is characterized by the development of small particles (granules) that collectively resemble breadcrumbs, usually during the second or third decade of life. These lesions slowly grow eventually combining (coalescing) to form larger lesions. Individuals may develop recurrent erosions. Although vision is usually unaffected early in the disease, decreased visual acuity may occur by the fourth or fifth decade. Some individuals may have an abnormal sensitivity to light (photophobia). Eye pain may result from recurrent corneal erosions.

Granular corneal dystrophy type II: In granular corneal dystrophy type II, also known as Avellino corneal dystrophy, lesions develop on the stroma usually beginning in the first or second decade of life. The opacities in the cornea sometimes resemble a cross between the granular lesions of granular corneal dystrophy type I and lattice lesions of lattice corneal dystrophy (see below). As affected individuals age, the lesions may become larger, more prominent and involve the entire stromal layer. Some older individuals have decreased clarity of vision (visual acuity) due to haze (clouding of the cornea). Recurrent erosions may develop in some cases. Courtesy of The Corneal Dystrophy Foundation.

Herpes simplex keratitis: Herpes keratitis is a viral infection of the eye caused by the herpes simplex virus, or HSV. There are two major types of the virus. Type I is the most common and primarily infects the face, causing the familiar "cold sore" or "fever blister." Type II is the sexually transmitted form of herpes, infecting the genitals.

Herpes zoster (shingles): The virus varicella zoster causes two distinct diseases. The primary infection causes chicken pox, a generally harmless childhood illness. After chicken pox ends, the virus remains in the body, where it can remain inactive (dormant) for decades. As a result of age, illness or medical treatments, the virus can become reactivated. This second encounter is called herpes zoster, or more commonly, shingles, and is characterized by a painful rash. Read more.

Juvenile rheumatoid arthritis associated with iridocyclitis: The arthritis usually manifests before iridocyclitis is noted. Reports suggest arthritis may be present one to 10 years before iridocyclitis; however, iridocyclitis may be the presenting disease.

Keratoconus: An uncommon condition in which the normally round, dome-like cornea (the clear front window of the eye) becomes thin and develops a cone-like bulge. Keratoconus literally means "cone-shaped cornea." Read more.

Lattice dystrophy: An accumulation of amyloid deposits, or abnormal protein fibers, throughout the middle and anterior stroma. During an eye examination, the doctor sees these deposits in the stroma as clear, comma-shaped overlapping dots and branching filaments, creating a lattice effect. Over time, the lattice lines will grow opaque and involve more of the stroma. They will also gradually converge, giving the cornea a cloudiness that may also reduce vision. Read more.

Lens-induced uveitis: Inflammation caused by a response of the immune system to leaking lens protein previously separated from major exposure to the immune system by the lens capsule. When the lens capsule is broken, the lens protein serves as an antigen stimulating immune response to the protein by the body's immune system. Capsular damage and leakage of protein does not usually lead to an inflammation, suggesting that other factors are involved.

Leprosy: In patients with leprosy, or Hansen's disease, the eyes frequently are affected with lagophthalmos, loss of eyebrows, corneal exposure, keratitis, uveitis, scleritis, leproma of the conjunctiva and sclera, retinal pearls, and loss of sensation with corneal ulceration with scarring. Read more.

Leptospirosis: A bacterial disease that affects humans and animals. It is caused by bacteria of the genus Leptospira. In humans, it can cause a wide range of symptoms, some of which may be mistaken for other diseases. Some infected persons, however, may have no symptoms at all. Without treatment, Leptospirosis can lead to kidney damage, meningitis (inflammation of the membrane around the brain and spinal cord), liver failure, respiratory distress and even death. Read more.

Lyme disease: An infection caused by a spirochete (“SPY-ROH-KEET”) that humans can get from the bite of an infected deer tick. The spirochete's scientific name is Borrelia burgdorferi. Lyme disease is called “The Great Imitator” because its symptoms mimic many other diseases. It can affect any organ of the body, including the brain and nervous system, muscles and joints, and the heart. Read more.

Lymphoma of the eye: In contrast to other systemic lymphomas, which usually involve the retina and iris (the colored portion of the eye), primary intraocular lymphoma, or PIOL, involves the retina, vitreous and optic nerve. Eighty-percent of cases involve both eyes; many people with PIOL will develop lymphoma within the part of the brain called the cerebrum.

Map-dot-fingerprint dystrophy: Occurs when the epithelium's basement membrane develops abnormally (the basement membrane serves as the foundation on which the epithelial cells, which absorb nutrients from tears, anchor and organize themselves). When the basement membrane develops abnormally, the epithelial cells cannot properly adhere to it. This, in turn, causes recurrent epithelial erosions, in which the epithelium's outermost layer rises slightly, exposing a small gap between the outermost layer and the rest of the cornea. Read more.

Ocular surface neoplasia (tumor): An abnormal growth of tissue – Conjunctival-Associated Lymphoid Tumor, or CALT, also known as Mucosa-Associated Lymphatic Tissue, or MALT – caused by abnormal mature b-cells. Lymphoma can occur in the conjunctiva. These tumors typically look like salmon-colored patches on the eye and can be a sign of systemic lymphoma. Eye cancer specialists usually biopsy lymphoid tumors and the pathologist is requested to perform special immunologic and genetic studies on the tumor cells. These techniques are used to determine if the tumor is benign or malignant. Read more. Patient resource.

Polycythemia vera: A bone marrow disease that leads to an abnormal increase in the number of blood cells. The red blood cells are mostly affected. Read more.

Posterior polymorphous corneal dystrophy: This uncommon form of corneal dystrophy may present at birth (with clouding of the cornea) or later during life and is characterized by lesions affecting the endothelium. Most individuals do not develop symptoms (asymptomatic). Effects on the cornea may be slowly progressive. Both eyes are usually affected, but one eye may be more severely affected than the other (asymmetric). In severe cases, individuals with posterior polymorphous dystrophy may develop swelling (edema) of the stroma, an abnormal sensitivity to light (photophobia), decreased vision and the feeling (sensation) of foreign material in the eye. In rare cases, increased pressure with the eye (intraocular pressure) may occur. Courtesy of The Corneal Dystrophy Foundation.

Psoriatic arthritis: Up to 30% of people with psoriasis also develop psoriatic arthritis, which causes pain, stiffness and swelling in and around the joints. Psoriatic arthritis can develop at any time, but it most commonly appears between the ages of 30 and 50. Genes, the immune system and environmental factors are all believed to play a role in the onset of the disease. Read more.

Reactive arthritis: A painful form of inflammatory arthritis that develops in reaction to a bacterial infection. In the past, it went by the name "Reiter's syndrome." Now it belongs to the family of arthritis called "spondyloarthritis." Some patients with this type of arthritis also have eye redness and irritation. Read more.

Sarcoidosis: A systemic granulomatous process of unknown etiology. Ocular involvement is seen in approximately 27% of patients with systemically diagnosed sarcoidosis, and anterior uveitis occurs in 66% of this ocular involvement. Eye disease may be the major clinically visible sign of activity of the disease.

Squamous cell carcinoma of the eyelid: This tumor can locally invade the orbit and sinuses, but rarely metastasizes. It is the second most common malignant eyelid tumor, but is 10 times less common than basal cell carcinoma. It is the most common conjunctival cancer and may spill over onto the eyelid. Read more.

Stevens-Johnson syndrome: Also called erythema multiforme major, Stevens-Johnson syndrome is a disorder of the skin that can also affect the eyes. Read more.

Sympathetic ophthalmia: Chronic bilateral iridocyclitis following ocular penetrating injury or surgery may be due to sympathetic ophthalmia. The sympathetic ophthalmia may be mild or severe; it has been reported to occur initially as soon as five days or up to 42 years later, or it may become inactive and reactivate years later. It is characterized by chronic, persistent keratic precipitates, cells and flare; broad posterior synechiae formation; and occasionally Dalen-Fuchs nodules in the retinal pigment epithelium.

Syphilis: Iridocyclitis associated with syphilis is characteristically the acute iridocyclitis seen in secondary syphilis. Syphilis, however, is capable of presenting in many ways and should always be considered in any chronic inflammatory condition. Serologic evidence of previous syphilis is not always proof of association with active inflammation. In congenital syphilis, an interstitial keratitis may be seen with cells in the anterior chamber. Interstitial keratitis is usually seen in patients between five and 25 years of age in congenital disease and is usually bilateral; it may also occur in the late stages of acquired syphilis. Pain and photophobia are usually present with activation of the interstitial keratitis and persist as long as the corneal process is active. The iris may show stromal atrophy and have a moth-eaten appearance. Ghost keratic precipitates with hyalinization may be observed unchanged for years. Altered vascular permeability may result in prolonged presence of cells and flare. Evidence of interstitial keratitis or any chronic intraocular inflammatory process of uncertain diagnosis should suggest further testing for this etiology. A serologic evaluation should be carried out, and if evidence of syphilis is substantiated, a specialist in infectious disease should be consulted. This should help establish whether a relationship exists between previous disease and current ocular changes, as well as what, if any, therapy is indicated.

Toxocariasis: The parasitic disease, also known as roundworm infection, caused by the larvae of two species of Toxocara roundworms: Toxocara canis from dogs and, less commonly, Toxocara cati from cats. Toxocariasis is considered one of the Neglected Parasitic Infections, a group of five parasitic diseases that have been targeted by CDC for public health action. Read more.

Toxoplasmosis: A single-celled parasite called Toxoplasma gondii causes this disease. While the parasite is found throughout the world, more than 60 million people in the United States may be infected with the Toxoplasma parasite. Of those who are infected, very few have symptoms because a healthy person's immune system usually keeps the parasite from causing illness. However, pregnant women and individuals who have compromised immune systems should be cautious; for them, a Toxoplasma infection could cause serious health problems. Read more.

Tuberculosis of the eye: A multisystem infectious disease caused by Mycobacterium tuberculosis, or MTB, primarily affects the lungs and causes significant morbidity and mortality worldwide. Tuberculosis, or TB, however, may affect other organs, including the eye. Intraocular TB is usually not associated with clinical evidence of pulmonary TB, as up to 60% of extrapulmonary TB patients may not have pulmonary TB. In recent years, there is a growing concern for TB as a major public health problem, increasing the prevalence of tuberculous eye disease.

Ulcerative colitis: Inflammation and sores, called ulcers, in the lining of the large intestine and the rectum. Some scientists believe ulcerative colitis, an inflammatory bowel disease, is an autoimmune disorder – a condition that occurs when the immune system reacts inappropriately by attacking healthy tissue in the body. In addition to causing symptoms similar to Crohn’s disease, diverticular disease, and cancer, ulcerative colitis can trigger complications in other parts of the body, and some are even potentially life-threatening. Read more.

Vogt-Koyanagi-Harada syndrome: Acute inflammation involving anterior and posterior intraocular inflammation, headache, and neck stiffness of unknown etiology, and is considered a uveomeningitis. This syndrome has been reported to occur more frequently in people of Asian ancestry, but it is also more prevalent among American Indians, African Americans and Latin Americans. This condition can persist with chronic iridocyclitis as the primarily anterior segment disease. If the initial involvement of the other ocular structures is insufficient to produce lasting diagnostic changes, or if systemic manifestations such as meningeal signs of headache, neck stiffness, auditory symptoms, vitiligo, and alopecia are mild, the diagnosis may be very difficult to establish. The anterior segment changes may vary widely, even in clearly diagnosed posterior segment disease. Exudative retinal detachment is seen with a characteristic fluorescein angiogram, showing multiple areas of subretinal leakage that may coalesce to form large areas of bullous detachment. When the detachment subsides, a characteristic mottling of the retinal pigment epithelium is seen.

Whipple’s disease: Iridocyclitis associated with Whipple's disease or intestinal lipodystrophy may have an acute onset, but more characteristically the iridocyclitis is chronic and associated with vitritis and retinal involvement.