Diseases

Q fever

Q fever is a disease caused by infection with Coxiella burnetii, a bacterium that affects humans and other animals. This organism is uncommon, but may be found in cattle, sheep, goats and other domestic mammals, including cats and dogs. The infection results from inhalation of a spore-like small cell variant, and from contact with the milk, urine, feces, vaginal mucus, or semen of infected animals. Rarely, the disease is tick borne. The incubation period is 9–40 days. Humans are vulnerable to Q fever, and infection can result from even a few organisms. The bacterium is an obligate intracellular pathogenic parasite.

Qazi Markouizos syndrome

Qazi Markouizos syndrome (medical condition): A very rare syndrome characterized mainly by abnormal bone development and muscle problems.

Quebec platelet disorder

Quebec platelet disorder is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Quebec platelet disorder, or a subtype of Quebec platelet disorder, affects less than 200,000 people in the US population.

Quinquaud’s decalvans folliculitis

Quinquaud's decalvans folliculitis : A form of hair loss involving the gradual destruction and scarring of hair follicles which causes hair loss which spreads outwards from a central point.

Rabies

Rabies is a viral disease that causes acute inflammation of the brain in humans and other warm-blooded animals. Early symptoms can include fever and tingling at the site of exposure. These symptoms are followed by one or more of the following symptoms: violent movements, uncontrolled excitement, fear of water, an inability to move parts of the body, confusion, and loss of consciousness. Once symptoms appear it nearly always results in death. The time period between contracting the disease and the start of symptoms is usually one to three months; however, this time period can vary from less than one week to more than one year. The time is dependent on the distance the virus must travel to reach the central nervous system.

Rabson-Mendenhall syndrome

A very rare genetic disorder involving severe insulin resistance which is where the body fails to be able to use insulin which is needed to control blood sugar levels.

Radiation Maculopathy

Radiation maculopathy is a condition causing vision loss due to radiation therapy, often a delayed complication of treating <uveal melanoma or <head and neck cancers. It involves microvascular damage to the retina’s macula, leading to symptoms like macular edema, intraretinal hemorrhages, and capillary nonperfusion. While symptoms like visual distortion or blurring can occur, the most common initial finding is macular edema. Treatment primarily focuses on managing macular edema with <anti-VEGF agents and <steroids, but preventing the condition is the best strategy, and treatment outcomes are often modest or temporary.

Radio-ulnar synostosis type 1

Radioulnar synostosis type 1: A very rare syndrome characterized by fusion of the forearm bones (radius and ulna). The head of the radial bone is absent.

Radio-ulnar synostosis type 2

A very rare syndrome characterized by dislocation of the head of the radius (forearm bone) as well as fusion of the two forearm bones (radius and ulna).

Radioiodine-resistant thyroid cancer

Radioiodine-resistant (RAI-R) thyroid cancer, also known as radioiodine-refractory differentiated thyroid cancer (RAI-R DTC), occurs when thyroid cancer cells are unable to effectively uptake and utilize radioactive iodine in treatment. This resistance can lead to disease progression and potentially a poorer prognosis. RAI-R DTC is more common in older patients, those with advanced disease, and those with distant metastases. 

Raine syndrome

A very rare syndrome characterized mainly by increased bone density which ultimately results in death.

Rambaud Galian syndrome

A very rare syndrome characterized by the progressive deposition of a substance called hyaline in blood vessels of the digestive tract and kidneys. Calcification of the brain is also present.

Ramer Ladda syndrome

(medical condition): A rare genetic disorder characterized by fusion of the humerus (upper arm) and radial (lower arm) bones as well as other anomalies. See also Humeroradial synostosis syndrome:

Ramon Syndrome

A rare genetic condition characterized by cherubism, enlarged gums, epilepsy, mental deficiency and excessive body hair (hypertrichosis).

Ramos Arroyo Clark syndrome

A very rare genetic disorder characterized distinctive facial features, ductus arteriosus, mental retardation and vision problems.

Rapadilino syndrome

A rare genetic condition characterized primarily by a cleft palate which has a high arch and missing or underdeveloped kneecaps as well as other anomalies.

Recessive Dystrophic Epidermolysis Bullosa

The disease manifests at birth or shortly thereafter with generalized blistering and superficial erosions of intermediate severity that heal with atrophic scarring and milia formation. From adolescence to early adulthood, blistering tends to localize to folds, particularly axillae, groin, perianal area and natal cleft. Women may present with marked vulvovaginal and inframammary skin blistering. Other predilection sites include the base of the neck, the uppermost back, and the lumbosacral area. Nail dystrophy is typical but of variable severity. Mucosal lesions with blistering and scarring in the mouth are characteristic and can lead to microglossia (loss of lingual papillae and fusion of the tongue to the mouth floor) and ankyloglossia (obliteration of the oral vestibules and progressive restriction of oral aperture). Esophageal involvement is often severe and is associated with a risk of esophageal stricture that can impair intake of nutrients. Lesions of the lowermost portion of the genitourinary tract are also common and may lead to the development of vaginal strictures that may impair normal sexual function. Other less common extracutaneous features include external auditory canal stenosis or complete occlusion with varying degrees of hearing loss; corneal erosions, and anemia. Growth delay is rare. Patients may develop squamous cell carcinomas, with a cumulative risk reaching 23% by age 50 which is much lower than in either of the two generalized forms of RDEB (severe RDEB and intermediate RDEB).

Rectal neoplasm

Rectal neoplasm, also called colon cancer or large bowel cancer, includes cancerous growths in the colon, rectum and appendix. With 655,000 deaths worldwide per year, it is the third most common form of cancer and the second leading cause of cancer-related death in the Western world.[1] Many colorectal cancers are thought to arise from adenomatous polyps in the colon. These mushroom-like growths are usually benign, but some may develop into cancer over time. The majority of the time, the diagnosis of localized colon cancer is through colonoscopy. Therapy is usually through surgery, which in many cases is followed by chemotherapy.

Rectosigmoid neoplasm

A tumor that originates in the upper rectal area or sigmoid colon. The tumor may be benign or cancerous.

Recurrent peripheral facial palsy

Differentiate supranuclear facial palsy from peripheral (nuclear) facial palsy. Supranuclear palsy involves predominantly the lower part of the face. Emotional responses may be intact (e.g., the patient may not be able to show you his teeth but will smile in response to a joke). Peripheral, or nuclear facial, palsy affects all ipsilateral muscles of facial expression, resulting in paralysis of the entire ipsilateral side. The mouth is pulled at an angle to the normal side and may droop on the affected side, facial creases are effaced, and the eyelid may not close.

Recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis is a rare viral disease where tumors (papillomas) grow in the air passages leading from the nose and mouth into the lungs (respiratory tract). Although the tumors can grow anywhere in the respiratory tract, their presence in the larynx (voice box) causes the most frequent problems, a condition called laryngeal papillomatosis. The tumors may vary in size and grow very quickly. They often grow back even when removed. RRP is caused by two types of human papillomavirus (HPV), called HPV 6 and HPV 11. These tumors can recur frequently, may require repetitive surgery, and may interfere with breathing. The disease can be treated with surgery and antivirals.

Red cell phospholipid defect with hemolysis

A rare inherited blood disorder where the membranes of red blood cells are defective and the cells are at risk of being destroyed easily if exposed to certain drugs or possibly even viruses.