Diseases

Oral lichen planus

Oral lichen planus is a chronic autoimmune inflammatory condition affecting the lining of your mouth, usually resulting in characteristic lacy white patches. Oral lichen planus occurs most often on the inside of your cheeks but also can affect your gums, tongue, lips and other parts of your mouth. Oral lichen planus sometimes involves your throat or esophagus. While oral lichen planus usually begins during midlife, it can occur at any age. An initial episode of oral lichen planus may last for weeks or months. But unfortunately, oral lichen planus is usually a chronic condition and can last for many years. Although there's no cure, oral lichen planus can be managed with medications and home remedies.

Oral lichenoid lesions

A mouth condition where white lesions develop inside the mouth. Redness, blistering and ulceration may also occur. It is believed to be caused by an autoimmune condition where the body's immune system attacks tissue inside the mouth. Sometimes the condition can be caused by allergies to metals in mouth appliances that are installed but it can also be caused by other forms of mechanical injury to the mouth such as cheek biting

Oral pharyngeal disorders

Disorders involving the mouth and back of throat area including the pharynx. The disorder may include cancers, structural abnormalities, fungal disease, infections and inflammation. The type and severity of symptoms varies greatly depending on the type of disorder

Oral squamous cell carcinoma

A type of cancer that develops in the mucosal lining (epithelium) of the mouth and can affect lips, tongue, palate and tonsillar area, floor of the mouth. This cancer type tends to progress further into pharynx and invade tissues nearby.

 

Source: National Cancer Institute, Merck Manuals

 

Oral submucous fibrosis

A rare disorder involving inflammation and progressive fibrosis of tissues inside the mouth. The condition starts with redness, blistering and ulceration inside the mouth that is eventually replaced with stiff fibrous tissue as it heals. The inside of the mouth can become stiff and hinder oral functions such as eating, speaking and even opening the mouth. Even the pharynx may occasionally be involved. The condition can become cancerous. The disorder is often associated with chewing betel nuts in Asian and Indian areas.

Oral-facial cleft

A birth defect involving an opening or cleft in the upper lip as well openings or clefts in the soft or hard palate (roof of the mouth).

Orbital lymphoma

A tumor that develops in the soft tissue of the eye socket and can push against the eye causing problems with vision and eye movement.

Organic acidemia

Organic acidemia, also called organic aciduria, is a term used to classify a group of metabolic disorders which disrupt normal amino acid metabolism, particularly branched-chain amino acids, causing a buildup of acids which are usually not present.

Organic brain syndrome

Organic brain syndrome is a general term referring to many acute and chronic physical disorders that cause impaired mental function. It does not usually include psychiatric disorders. Though OBS is a common diagnosis in the elderly, it is related to disease processes and is not an inevitable part of aging.

Organic mood syndrome

Persistant mood changes due to physical causes such as a chemical imbalance rather than psychiatric causes. The duration and severity of the condition is determined by the nature and location of the cause.

Organic personality syndrome

Persistant personality changes due to physical causes such as a chemical imbalance rather than psychiatric causes. The duration and severity of the condition is determined by the nature and location of the cause.

Ornithine Transcarbamylase Deficiency

Ornithine Transcarbamylase Deficiency ( OTCD) is an inherited disorder that causes ammonia to accumulate in the blood. Ammonia, which is formed when proteins are broken down in the body, is toxic if the levels become too high. The nervous system is especially sensitive to the effects of excess ammonia. Ornithine transcarbamylase deficiency often becomes evident in the first few days of life. An infant with ornithine transcarbamylase deficiency may be lacking in energy (lethargic) or unwilling to eat, and have poorly-controlled breathing rate or body temperature. Some babies with this disorder may experience seizures or unusual body movements, or go into a coma. Complications from ornithine transcarbamylase deficiency may include developmental delay and intellectual disability. Progressive liver damage, skin lesions, and brittle hair may also be seen.

Ornithinemia

A toxic condition occasionally producing localized cerebral swelling, caused by abnormal amounts of ornithine in the blood. [ornithine + G. haima, blood] Source: Stedman's Medical Spellchecker, © 2006 Lippincott Williams & Wilkins. All rights reserved.

Oro acral syndrome

A very rare syndrome characterized mainly by mouth and limb abnormalities.

Orofaciodigital syndrome 4

A rare inherited disorder characterized by facial, digital and oral abnormalities. Type IV is differentiated from the other types by the presence of severe shinbone deformity.

Orofaciodigital syndrome type1

A rare genetic disorder characterized by variable malformations of the face, digits and inside the mouth. Type 1 is distinguished from the other types of this condition by the presence of polycystic kidneys and a X-linked dominant inheritance

Oropharyngeal cancer- adult

Cancer of the back of the mouth which forms part of the throat including the back of the tongue, tonsils, part of the throat wall and soft palate (oropharynx).

Orotic aciduria hereditary

A rare metabolic disorder where an inherited enzyme deficiency (lack of orotidylic pyrophosphorylase and orotidylic decarboxylase or a lack of orotidylic decarboxylase only) impairs the body's ability to break down orotic acid, leading to excessive excretion of orotic acid in urine. It causes a characteristic form of anemia and may be associated with mental and physical retardation.

Orotic aciduria purines-pyrimidines

This is a rare, X-linked, recessive disorder caused by deficiency of hypoxanthine-guanine phosphoribosyl transferase (HPRT); degree of deficiency (and hence manifestations) vary with the specific mutation. HPRT deficiency results in failure of the salvage pathway for hypoxanthine and guanine. These purines are instead degraded to uric acid. Additionally, a decrease in inositol monophosphate and guanosyl monophosphate leads to an increase in conversion of 5-phosphoribosyl-1-pyrophosphate (PRPP) to 5-phosphoribosylamine, which further exacerbates uric acid overproduction. Hyperuricemia predisposes to gout and its complications. Patients also have a number of cognitive and behavioral dysfunctions, etiology of which is unclear; they do not appear related to uric acid.

Oroticaciduria 1

A rare metabolic disorder where deficiency of two enzymes (orotidylic pyrophosphorylase and orotidylic decarboxylase) which impairs the body's ability to break down orotic acid which then builds up in the body where it can cause damage.

Orotidylic decarboxylase deficiency

A rare metabolic disorder where deficiency of an enzyme (orotidylic decarboxylase) which impairs the body's ability to break down orotic acid which then builds up in the body where it can cause damage.

Orthostatic Hypotension

Orthostatic hypotension, colloquially known as head rush or dizzy spell, is a form of low blood pressure in which a person's blood pressure falls when suddenly standing up or stretching. In medical terms, it is defined as a fall in systolic blood pressure of at least 20 mm Hg or diastolic blood pressure of at least 10 mm Hg when a person assumes a standing position.

Orthostatic intolerance

A condition where various symptoms occur when a person moves to an upright position such as standing after sitting down or sitting up after lying down. It is due to problems with blood flow, blood pressure and heart rate