Glossary for Infections, Disorders and Diseases

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

A

ANCA – ANCA stands for anti-neutrophilic cytoplasmic antibodies. These are a class of antibodies identified by immunofluorescence.

Anthrax – Anthrax is an acute infectious disease caused by the spore-forming bacterium Bacillus anthracis. Anthrax most commonly occurs in wild and domestic lower vertebrates (cattle, sheep, goats, camels, antelopes, and other herbivores), but it can also occur in humans when they are exposed to infected animals or tissue from infected animals.

Anti-Cardiolipin – Anti-cardiolipin antibodies (ACA) are antibodies often directed against cardiolipin and found in several diseases including syphilis, antiphospholipid syndrome, livedoid vasculitis, vertebrobasilar insufficiency, Behçet’s syndrome, idiopathic spontaneous abortion, and systemic lupus erythematosus(SLE). They are a form of anti-mitochondrial antibody. In SLE, The anti-DNA antibodies and anti-cardiolipin act independently. In rheumatoid arthritis w/systemic sclerosis (scleroderma) these antibodies may tie two conditions together.

Antiphospholipid Syndrome – Antiphospholipid syndrome is defined as the presence of antiphospholipid antibodies, arterial or venous thrombosis, recurrent spontaneous abortions, and thrombocytopenia. However, not all patients develop such complications.

Arthritis – Arthritis is an illness that can cause pain and swelling in your joints. Joints are places where two bones meet, such as your elbow or knee. Some kinds of arthritis can cause problems in other organs, such as your eyes, or in your chest. It can affect your skin, too.

Aspergillus – Aspergillus is a genus of around 200 molds found throughout much of nature worldwide. Aspergillus was first catalogued in 1729 by the Italian priest and biologist Pier Antonio Micheli. Viewing the fungi under a microscope, Micheli was reminded of the shape of an aspergillum (holy water sprinkler), and named the genus accordingly.

B

Beryllium Disease – Beryllium disease is a condition that can occur from exposure to beryllium dust or fumes.

C

C-ANCA – c-ANCAs, or cytoplasmic-staining antineutrophil cytoplasmic antibodies, show a diffusely granular, cytoplasmic staining pattern. This pattern results from binding of ANCA to antigen targets throughout the neutrophil cytoplasm, the most common protein target being proteinase 3 (PR3). PR3 is the most common antigen target of ANCA in patients with Wegener’s granulomatosis. Other antigens may also occasionally result in a c-ANCA pattern.

Candida – Candida is a genus of yeasts. Many species of this genus are endosymbionts of animal hosts including humans. While usually living as commensals, some Candida species have the potential to cause disease. Clinically, the most significant member of the genus is Candida albicans, which can cause infections (called candidiasis or thrush) in humans and other animals, especially in immunocompromised patients. Many Candida species are members of gut flora in animals, including C. albicans in mammalian hosts, whereas others live as endosymbionts in insect hosts.

Cardiolipin – An anionic phospholipid that is uniquely localized in the inner mitochondrial membrane and that is of vital importance for the function of the respiratory chain and the adenine nucleotide translocator.

Celiac Disease – Celiac disease is a digestive disease that damages the small intestine and interferes with absorption of nutrients from food. People who have celiac disease cannot tolerate a protein called gluten, found in wheat, rye, and barley. Gluten is found mainly in foods but may also be found in products we use every day, such as stamp and envelope adhesive, medicines, and vitamins.

Chagas Disease – Chagas’ disease (also called American trypanosomiasis) is a human tropical parasitic disease which occurs in the Americas, particularly in South America. Its pathogenic agent is a flagellate protozoan named Trypanosoma cruzi, which is transmitted to humans and other mammals mostly by blood-sucking assassin bugs of the subfamily Triatominae (Family Reduviidae). Those insects are known by numerous common names varying by country, including benchuca, vinchuca, kissing bug, chipo, pito, chupança, and barbeiro. The most common insect species belong to the genera Triatoma, Rhodnius, and Panstrongylus. However, other methods of transmission are possible, such as ingestion of food contaminated with parasites, blood transfusion and fetal transmission.

Chicken Pox – Chickenpox is a common illness among kids, particularly those under age 12. An itchy rash of spots that look like blisters can appear all over the body and may be accompanied by flu-like symptoms. Symptoms usually go away without treatment, but because the infection is very contagious, an infected child should stay home and rest until the symptoms are gone.

Chlamydia – Chlamydia is a genus of obligate intracellular bacteria in the family Chlamydiaceae, order Chlamydiales, class and phylum Chlamydiae. The three species in this genus are Chlamydia trachomatis (affects only humans), Chlamydia suis (affects only swine), and Chlamydia muridarum (affects only mice and hamsters). Chlamydia infection is the most common bacterial sexually transmitted disease and the leading cause of infectious blindness in the world.

Crohns Disease – Crohn’s disease is an ongoing disorder that causes inflammation of the digestive tract, also referred to as the gastrointestinal (GI) tract. Crohn’s disease can affect any area of the GI tract, from the mouth to the anus, but it most commonly affects the lower part of the small intestine, called the ileum. The swelling extends deep into the lining of the affected organ. The swelling can cause pain and can make the intestines empty frequently, resulting in diarrhea.

Cytomegalovirus (CMV) – One group of herpes viruses that infect humans and can cause a variety of clinical symptoms including deafness or hearing impairment; infection with the virus may be either before or after birth.

D

Dementia – Dementia is chronic, global, usually irreversible deterioration of cognition. Diagnosis is clinical; laboratory and imaging tests are used to identify treatable causes. Treatment is supportive. Cholinesterase inhibitors can sometimes temporarily improve cognitive function.

Dengue – Dengue is a mosquito-borne disease caused by a flavivirus. Dengue fever usually results in the abrupt onset of high fever, headache, myalgias, arthralgias, lymphadenopathy, and a rash that appears with a 2nd temperature rise after an afebrile period. Respiratory symptoms, such as cough, sore throat, and rhinorrhea, can occur. Dengue can also cause potentially fatal hemorrhagic fever with bleeding tendency and shock. Diagnosis involves PCR and serologic testing. Treatment is symptomatic, including meticulously adjusted intravascular volume replacement.

DNA Virus – A DNA virus is a virus that has DNA as its genetic material and replicates using a DNA-dependent DNA polymerase. The nucleic acid is usually double-stranded DNA (dsDNA) but may also be single-stranded DNA (ssDNA). DNA viruses belong to either Group I or Group II of the Baltimore classification system for viruses. Single-stranded DNA is usually expanded to double-stranded in infected cells. Although Group VII viruses such as hepatitis B contain a DNA genome, they are not considered DNA viruses according to the Baltimore classification, but rather reverse transcribing viruses because they replicate through an RNA intermediate.

E

Eclampsia – Eclampsia is unexplained generalized seizures in patients with preeclampsia. Preeclampsia and eclampsia develop between 20 wk gestation and the end of the 1st wk postpartum. Diagnosis is clinical and by urine protein measurement. Treatment is with IV Mg sulfate and usually rapid delivery.

Ectropion – A condition that results in outward-turning eyelids. The migration of cells from the lining of the endocervical canal (endocervix) to the outer portion of the cervix (ectocervix). Often mistakenly termed cervical erosion.

Edema – Edema is the accumulation of fluid in bodily tissues or a body cavity. The word edema is derived from the Middle English word ydema, which comes from the Greek word for “swelling.” Edema is an observable condition in which the swelling is usually apparent. Most commonly found in the feet and legs, edema occurs beneath the skin in the spaces within the body tissues outside of the blood vessels, called interstitial spaces or compartments.

Encephalitis – Encephalitis is an inflamation of the brain and spinal cord usually caused by viral infection. Diseases such as rabies, polyomelitis, and herpes encephalitis are all caused by virus infections that affect the brain and spinal cord and are transmitted in a variety of ways.

Epstein-Barr Virus – The Epstein-Barr Virus (EBV), also called Human herpesvirus 4 (HHV-4), is a virus of the herpes family (which includes Herpes simplex virus and Cytomegalovirus), and is one of the most common viruses in humans. Most people become infected with EBV, which is often asymptomatic but commonly causes infectious mononucleosis.

Esotropia – The deviation of an eye inward, sometimes referred to as “cross-eyed.”

F

Fasciitis – Inflammation of the fascia (a lining tissue under the skin that covers a surface of underlying tissues).

Fibrosis – Abnormal formation of scar tissue.

Fucosidosis – Fucosidosis is an autosomal recessive disease in which fucosidase is not properly used in the cells to break fucose.

G

Giardia – Giardia lamblia (synonymous with Lamblia intestinalis and Giardia duodenalis) is a flagellated protozoan parasite that colonises and reproduces in the small intestine, causing giardiasis. The giardia parasite attaches to the epithelium by a ventral adhesive disc, and reproduces via binary fission. Giardiasis does not spread via the bloodstream, nor does it spread to other parts of the gastro-intestinal tract, but remains confined to the lumen of the small intestine. Giardia trophozoites absorb their nutrients from the lumen of the small intestine, and are anaerobes.

Gliadin – Gliadin is a glycoprotein, present in wheat and some other cereals, best known for its role, along with glutenin, in the formation of gluten. It is around 60 percent soluble in ethanol and sports only intramolecule disulfide links.

H

HIV – Human immunodeficiency virus (HIV) is a retrovirus that can lead to acquired immunodeficiency syndrome (AIDS), a condition in humans in which the immune system begins to fail, leading to life-threatening opportunistic infections.

Helicobacter pylori – Helicobacter pylori is a gram-negative, microaerophilic bacterium that infects various areas of the stomach and duodenum. Many cases of peptic ulcers, gastritis, duodenitis, and cancers are caused by H. pylori infections. However, many who are infected do not show any symptoms of disease. H. pylori’s helical shape (from which the genus name is derived) is thought to have evolved to penetrate and favor its motility in the mucus gel layer.

Hepatitis A (HAV) – Very contagious disease that results in inflammation of the liver, usually caught by eating or drinking food or water contaminated by infected sewage. There is a vaccine to prevent this disease.

Hepatitis B (HBC) – Hepatitis caused by a virus and transmitted by exposure to blood or blood products or during sexual intercourse. It causes acute and chronic hepatitis. Chronic hepatitis B can cause liver disease, cirrhosis, and liver cancer.

Hepatitis B viral DNA (HBV DNA) – The hepatitis B virus contains DNA. If DNA from the hepatitis B virus is found in your blood sample, then your health professional knows that the virus is multiplying.

Hepatitis C (HVC) – Hepatitis C is a life-threatening, blood borne disease of the liver, which is transmitted by exposure to blood. A particularly dangerous form of viral hepatitis, it is caused by an RNA virus. Hepatitis C can lead to serious, permanent liver damage, and in many cases, death. More than 80 percent of those who are infected will progress to chronic liver disease.

Herpes (HSV-1) – Herpes is a virus that can spread from person to person through skin-to-skin contact. It can appear on many different areas of the body and is typically marked by an eruption of a cluster of blisters, although some people show very mild or no symptoms at all. HSV type 1 most commonly causes sores on the lips and is often referred to as fever blisters or cold sores.

Herpes Simplex (HSV-2) – Herpes simplex is a viral disease caused by Herpes simplex viruses; both herpes simplex virus 1 (HSV–1) and herpes simplex virus 2 (HSV–2) cause herpes simplex. Infection with the herpes virus is categorized into one of several distinct disorders based on the site of infection. HSV type 2 is most often related to infections and symptoms of genital herpes, but it also can infect the mouth.

Histoplasmosis – Histoplasmosis, also known as Darling’s disease, is a disease caused by the fungus Histoplasma capsulatum which was discovered in 1905. Its symptoms vary greatly, but the disease primarily affects the lungs. Occasionally, other organs are affected—this form of the disease is called disseminated histoplasmosis, and it can be fatal if untreated.

I

Ichthyosis – Any of several generalized skin disorders characterized by dryness, roughness, and scaliness, due to hypertrophy of the stratum corneum epidermis. Most are genetic, but some are acquired, developing in association with other systemic disease or genetic syndrome.

Insulinoma – A tumor of the beta cells in areas of the pancreas called the islets of Langerhans. Although not usually cancerous, such tumors may cause the body to make extra insulin and may lead to a blood glucose (sugar) level that is too low.

J

Jaundice – Jaundice is a condition easily recognized by its symptoms of yellowed skin and sclera (the whites of the eyes), due to an accumulation of bilirubin in the body.

K

Keratitis – Inflammation of the cornea of the eye; may be caused by infection, trauma, or an allergic reaction.

Kuru – Kuru is a disease which affects the brain. It was endemic among the Fore tribe of Papua New Guinea and was universally fatal. It is characterized by headaches, joint pains and shaking of the limbs. It is believed to be caused by prions and is related to Creutzfeldt-Jakob disease. It is best known for the epidemic that occurred in Papua New Guinea in the middle of the twentieth century. It is also known as the laughing sickness due to the pathologic bursts of laughter the patient displays when afflicted with the disease.

L

Laryngitis – Laryngitis is an inflammation of the part of the throat called the larynx or voice box.

Leptospira – (from the Greek leptos, meaning fine or thin, and the Latin spira, meaning coil) is a genus of spirochaete bacteria, including a small number of pathogenic and saprophytic species. Leptospira was first observed in 1907 in kidney tissue slices of a leptospirosis victim who was described as having died of “yellow fever.”

Lupus – The immune system is designed to attack foreign substances in the body. If you have lupus, something goes wrong with your immune system and it attacks healthy cells and tissues.

Lyme Disease – Lyme disease is the most common tick-borne disease in the Northern Hemisphere. Borrelia is transmitted to humans by the bite of infected hard ticks belonging to several species of the genus Ixodes. Early manifestations of infection may include fever, headache, fatigue, and a characteristic skin rash called erythema migrans. Left untreated, late manifestations involving the joints, heart, and nervous system can occur. In a majority of cases, symptoms can be eliminated with antibiotics, especially if diagnosis and treatment occur early in the course of illness. Late, delayed, or inadequate treatment can lead to late manifestations of Lyme disease which can be disabling and difficult to treat.

M

Macroglossia – Macroglossia is tongue enlargement that leads to functional and cosmetic problems. Although this is a relatively uncommon disorder, it may cause significant morbidity. There is no clear definition of macroglossia and it may be defined in relative, functional, or structural terms. Clinical studies are limited by this lack of a clear definition.

Mitochondrial Disease – Mitochondrial diseases are a group of disorders relating to the mitochondria, the organelles that are the “powerhouses” of the eukaryotic cells that comprise higher-order lifeforms (including humans). The mitochondria convert the energy of food molecules into the ATP that powers most cell functions. Mitochondrial diseases comprise those disorders that in one way or another affect the function of the mitochondria and/or are due to mitochondrial DNA. Mitochondrial diseases take on unique characteristics both because of the way the diseases are often inherited and because mitochondria are so critical to cell function. The subclass of these diseases that have neuromuscular disease symptoms are often referred to as a mitochondrial myopathy.

Mono – Mono is contagious, which means you can spread the virus to other people who haven’t had mono before. Even though you can get mono from kissing someone infected with EBV, there are also other ways you can get it, but they all involve contact with saliva. Sharing pillows, straws, toothbrushes, or food from the same plate also spread mono.

Mononucleosis – Infectious mononucleosis, also known as Pfeiffer’s disease, mono (in North America) and more commonly known as glandular fever in other English-speaking countries. It occurs most commonly in adolescents and young adults, where it is characterized by fever, sore throat, muscle soreness, and fatigue. Infectious mononucleosis typically produces a mild illness in small children, and is often asymptomatic. Mononucleosis is predominantly caused by the Epstein-Barr virus (EBV), which infects B cells (B-lymphocytes), producing a reactive lymphocytosis predominantly consisting of atypical lymphocytes, a specific type of T-cell that gives the disease its name.

N

Neoplasm – A new growth of tissue serving no physiological function.

Nephrosis – Nephrosis is a medical term for kidney disease. Sometimes called nephrotic syndrome or nephropathy, nephrosis has numerous possible causes. Nephrosis is typically diagnosed by the results of a urine test, and though treatment varies with the cause, it often requires life long treatment with the hope of preventing permanent kidney failure.

O

Oliguria – Oliguria is defined as a urine output that is less than 1 mL/kg/h in infants, less than 0.5 mL/kg/h in children, and less than 400 mL/day (equals 17mL/hour) in adults.

Onychomychosis – Onychomycosis (OM) refers to a fungal infection that affects the toenails or the fingernails. It may involve any component of the nail unit, including the nail matrix, the nail bed, or the nail plate. OM is not life threatening, but it can cause pain, discomfort, and disfigurement and may produce serious physical and occupational limitations.

P

Parpovirus – Commonly abbreviated to parvo, is a genus of the Parvoviridae family linear, non-segmented single stranded DNA viruses with an average genome size of 5 kbp. Parvoviruses are some of the smallest viruses found in nature (hence the name, from Latin parvus meaning small). Some have been found as small as 23nm.

Parietal Cell – Parietal cells produce gastric acid (hydrochloric acid) in response to histamine (via H2 receptors), acetylcholine (M3 receptors) and gastrin (CCK2 receptors). The histamine receptors act by increasing intracellular cAMP, whereas the muscarinic and gastrin receptors increase intracellular Ca2+ levels. Both cAMP and Ca2+ acts via protein kinases to increase the transport of acid into the stomach.

Pneumonia – Pneumonia is an inflammatory illness of the lung.[1] Frequently, it is described as lung parenchyma/alveolar inflammation and abnormal alveolar filling with fluid. (The alveoli are microscopic air-filled sacs in the lungs responsible for absorbing oxygen from the atmosphere.) Pneumonia can result from a variety of causes, including infection with bacteria, viruses, fungi, or parasites, and chemical or physical injury to the lungs. Its cause may also be officially described as idiopathic—that is, unknown—when infectious causes have been excluded.

Q

Q Fever – Q fever is a disease caused by infection with Coxiella burnetii, a bacterium that affects both humans and 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 contaminated particles in the air, and from contact with the vaginal mucus, milk, feces, urine or semen of infected animals. The incubation period is 9-40 days. It is considered possibly the most infectious disease in the world, as a human being can be infected by a single bacterium.

Quadriplegia – Quadriplegia, also known as tetraplegia, is a symptom in which a human experiences paralysis affecting all four limbs, although not necessarily total paralysis or loss of function.

R

Ranula – A ranula is a type of mucocele found on the floor of the mouth. Ranulas present as a swelling of connective tissue consisting of collected mucin from a ruptured salivary gland duct, which is usually caused by local trauma.

Retinoblastoma – Retinoblastoma is a cancer of the retina. Development of this tumor is initiated by mutations that inactivate both copies of the RB1 gene, which codes for the retinoblastoma protein.

Rheumatoid Arthritis – Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disorder that causes the immune system to attack the joints, causing inflammation (arthritis), and some organs, such as the lungs and skin. It can be a disabling and painful condition, which can lead to substantial loss of functioning mobility due to pain and joint destruction. It is diagnosed with blood tests (especially a test called rheumatoid factor) and X-rays. Diagnosis and long-term management are typically performed by a rheumatologist, an expert in the diseases of joints and connective tissues.

Ribonucleoprotein (RNP) – Ribonucleoprotein is a nucleoprotein that contains RNA, i.e. it is a compound that combines ribonucleic acid and protein together. It is one of the main components of nucleolus. RNP is an RNA binding motif in an RNA binding protein. Aromatic amino acid residues in this RNP motif result in stacking interactions with RNA. Lysine residues in the helical portion of RNA binding proteins help to stabilize interactions with nucleic acids. This nucleic acid binding is a result of highly positive nature of lysine side chains and the negative character of nucleic acid phosphate backbones.

Rocky Mountain Spotted Fever – Rocky Mountain spotted fever is the most severe and most frequently reported rickettsial illness in the United States. It has been diagnosed throughout the Americas. Some synonyms for Rocky Mountain spotted fever in other countries include “tick typhus,” “Tobia fever” (Colombia), “São Paulo fever” or “febre maculosa” (Brazil), and “fiebre manchada” (Mexico). It should not be confused with the viral tick-borne infection, Colorado tick fever. The disease is caused by Rickettsia rickettsii, a species of bacterium that is spread to humans by ixodid (hard) ticks. Initial signs and symptoms of the disease include sudden onset of fever, headache, and muscle pain, followed by development of rash. The disease can be difficult to diagnose in the early stages, and without prompt and appropriate treatment it can be fatal.

Rubella – Rubella, commonly known as German measles, is a disease caused by Rubella virus. The name is derived from the Latin, meaning little red. Rubella is also known as German measles because the disease was first described by German physicians in the mid-eighteenth century. This disease is often mild and attacks often pass unnoticed. The disease can last one to five days. Children recover more quickly than adults. Infection of the mother by Rubella virus during pregnancy can be serious; if the mother is infected within the first 20 weeks of pregnancy, the child may be born with congenital rubella syndrome (CRS), which entails a range of serious incurable illnesses.

Rubeola – Measles, also called rubeola, is a highly contagious — but rare — respiratory infection that’s caused by a virus. It causes a total-body skin rash and flu-like symptoms, including a fever, cough, and runny nose.

S

Saccharomyces – Saccharomyces is a genus in the kingdom of fungi that includes many species of yeast. Saccharomyces is from Latin meaning sugar fungi. Many members of this genus are considered very important in food production. One example is Saccharomyces cerevisiae, which is used in making wine, bread, and beer. Other members of this genus include Saccharomyces bayanus, used in making wine, and Saccharomyces boulardii, used in medicine.

Scleroderma – Scleroderma is a chronic disease characterized by excessive deposits of collagen in the skin or other organs. The localized type of the disease, while disabling, tends not to be fatal. The systemic type or systemic sclerosis, the generalized type of the disease, can be fatal as a result of heart, kidney, lung or intestinal damage autoimmune disease.

Sjogren’s – Sjogren’s syndrome is an autoimmune disease. Autoimmune diseases are characterized by the abnormal production of extra antibodies in the blood that are directed against various tissues of the body. This particular autoimmune illness features inflammation in certain glands of the body. Inflammation of the glands that produce tears (lacrimal glands) leads to decreased water production for tears and eye dryness. Inflammation of the glands that produce the saliva in the mouth (salivary glands, including the parotid glands) leads to mouth dryness.

Smooth Muscle – Smooth muscle is a type of non-striated muscle, found within the tunica media layer of arteries and veins, the bladder, uterus, male and female reproductive tracts, gastrointestinal tract, respiratory tract, the ciliary muscle, and iris of the eye. The glomeruli of the kidneys contain a smooth muscle-like cell called the mesangial cell. Smooth muscle is fundamentally different from skeletal muscle and cardiac muscle in terms of structure, function, excitation-contraction coupling, and mechanism of contraction.

Syphilis – Syphilis is a curable sexually transmitted disease caused by the Treponema pallidum spirochete. The route of transmission of syphilis is almost always by sexual contact, although there are examples of congenital syphilis via transmission from mother to child in utero. The signs and symptoms of syphilis are numerous; before the advent of serological testing, precise diagnosis was very difficult. In fact, the disease was dubbed the “Great Imitator” because it was often confused with other diseases, particularly in its tertiary stage. Syphilis (unless antibiotic-resistant) can be easily treated with antibiotics including penicillin. The oldest and still most effective method is an intramuscular injection of benzathine penicillin. If not treated, syphilis can cause serious effects such as damage to the heart, aorta, brain, eyes, and bones. In some cases these effects can be fatal.

T

Thyroglobulin – Thyroglobulin (Tg) is a 660 kDa, dimeric protein produced by and used entirely within the thyroid gland. In earlier literature, Tg was referred to as “colloid”. Thyroglobulin should not be confused with Thyroxine-binding globulin, a carrier protein responsible for carrying the thyroid hormones in the blood.

Thyroid – The thyroid is one of the largest endocrine glands in the body. This gland is found in the neck inferior to (below) the thyroid cartilage (also known as the Adam’s apple in men) and at approximately the same level as the cricoid cartilage. The thyroid controls how quickly the body burns energy, makes proteins, and how sensitive the body should be to other hormones.

Thyroid Peroxidase – Thyroid peroxidase or Thyroperoxidase (TPO) is an enzyme mainly expressed in the thyroid that liberates iodine for addition onto tyrosine residues on thyroglobulin for the production of thyroxine (T4) or triiodothyronine (T3) (thyroid hormones). Inorganic iodine enters the body primarily as iodide, I-. After entering the thyroid follicle (or thyroid follicular cell) via a Na+/I- symporter (NIS) on the basolateral side, iodide is shuttled across the apical membrane into the colloid via pendrin, after which thyroid peroxidase oxidizes iodide to atomic iodine (I) or iodinium (I+). The “organification of iodine,” the incorporation of iodine to thyroglobulin for the production of thyroid hormone is inseparable from oxidation and is catalyzed by TPO. The chemical reactions catalyzed by thyroid peroxidase occur on the outer apical membrane surface and are mediated by hydrogen peroxide.

Tissue Transglutaminase – Tissue transglutaminase (abbreviated as TG2 or tTG) is an enzyme of the transglutaminase family. Like other transglutaminases, it crosslinks proteins between an ε-amino group of a lysine residue and a γ-carboxamide group of glutamine residue, creating an inter- or intramolecular bond that is highly resistant to proteolysis (protein degradation). It is particularly notable for being the autoantigen in coeliac disease, but is also known to play a role in apoptosis, cellular differentiation and matrix stabilisation.

U

UROD Deficiency – Lack of the enzyme uroporphyrinogen decarboxylase (UROD) which is the basic cause of porphyria cutanea tarda (PCT), the late skin form of porphyria. PCT is a genetic photosensitive (light-sensitive) skin disease with onset in adult life with a large amount of a substance called uroporphyrin in the urine. UROD is an enzyme required for the synthesis of heme (part of hemoglobin, the pigment in red blood cells that carries oxygen). The hallmarks of porphyria cutanea tarda (PCT) are blisters which become ulcerated in areas of the skin exposed to sunlight, especially on the face, ears and dorsum (back) of the hands. The affected areas of skin also tend to be fragile and show hyperpigmentation (excess pigment) and hypertrichosis (excess hair).

UROS Deficiency – Mutations in the UROS gene cause congenital erythropoietic porphyria. The UROS gene makes an enzyme called uroporphyrinogen III synthase, which is critical to the chemical process that leads to haeme production. If gene mutations prevent sufficient activity of this enzyme, haeme is not produced normally. Instead, byproducts of the process called porphyrins build up in the body (particularly in the skin), causing the signs and symptoms of this form of porphyria.

Usher Syndrome – Usher syndrome is the most common condition that affects both hearing and vision. A syndrome is a disease or disorder that has more than one feature or symptom. The major symptoms of Usher syndrome are hearing loss and an eye disorder called retinitis pigmentosa, or RP. RP causes night-blindness and a loss of peripheral vision (side vision) through the progressive degeneration of the retina.

Uveitis – Uveitis specifically refers to inflammation of the middle layer of the eye, termed the “uvea” but in common usage may refer to any inflammatory process involving the interior of the eye. Uveitis is estimated to be responsible for approximately 10% of the blindness in the United States. Uveitis requires an urgent referral and thorough examination by an ophthalmologist, along with urgent treatment to control the inflammation.

V

VHL Syndrome – Von Hippel-Lindau syndrome is an inherited multi-system disorder characterized by abnormal growth of blood vessels. While blood vessels normally grow like trees, in people with VHL little knots of blood capillaries sometimes occur. These knots are called angiomas or hemangioblastomas. Growths may develop in the retina, certain areas of the brain, the spinal cord, the adrenal glands and other parts of the body.

Vertigo – Vertigo is a specific type of dizziness, a major symptom of a balance disorder. It is the sensation of spinning or swaying while the body is stationary with respect to the earth or surroundings. There are two types of vertigo: subjective and objective. There is a subjective vertigo when a person has a false sensation of movement. In the case of objective vertigo, the surroundings appear to move past a person’s field of vision. The effects of vertigo may be slight. It can cause nausea and vomiting and, in severe cases, it may give rise to difficulties with standing and walking.

W

West Nile Virus – West Nile virus (or WNV) is a virus of the family Flaviviridae; part of the Japanese encephalitis (JE) antigenic complex of viruses, it is found in both tropical and temperate regions. It mainly infects birds, but is known to infect humans, horses, dogs, cats, bats, chipmunks, skunks, squirrels, and domestic rabbits. The main route of human infection is through the bite of an infected mosquito.

Wilson’s Disease – Wilson’s disease or hepatolenticular degeneration is an autosomal recessive genetic disorder in which copper accumulates in tissues; this manifests as neurological or psychiatric symptoms and liver disease. It is treated with medication that reduces copper absorption or removes the excess copper from the body, but occasionally a liver transplant is required.

X

Xanthoma – A xanthoma (or xanthomata or xanthomatosis) (from Greek xanthos, ξανθος, “yellow”) is a deposition of yellowish cholesterol-rich material in tendons and other body parts in various disease states.

Xerostomia – Xerostomia is the medical term for a dry mouth due to a lack of saliva. Xerostomia is sometimes colloquially called pasties, cottonmouth, or doughmouth. Xerostomia can cause difficulty in speech and eating. It also leads to halitosis and a dramatic rise in the number of cavities, as the protective effect of saliva’s remineralizing the enamel is no longer present, and can make the mucosa of the mouth more vulnerable to infection. Notably, a symptom of methamphetamine use usually called “meth mouth” is largely caused by xerostomia which is worsend by the fact that methamphetamine at recreational doses can cause tight clenching of the jaw, bruxism (compulsive grinding of the teeth), or a repetitive ‘chewing’ movement like the user is chewing without food in the mouth. Also people who prolong or ‘binge’ use of methamphetamine sometimes do not give the same amount priority to hygiene as they would without the methamphetamine.

Y

Yaws – Yaws (also Pétasse tropica, thymosis, polypapilloma tropicum or pian) is a tropical infection of the skin, bones and joints caused by the spirochete bacterium Treponema pertenue.

Yellow Fever – Yellow fever (also called yellow jack, black vomit or sometimes American Plague) is an acute viral disease. It is an important cause of hemorrhagic illness in many African and South American countries despite existence of an effective vaccine. The yellow refers to the jaundice symptoms that affect some patients.

Z

Zellweger Syndrome – Zellweger syndrome is one of a group of four related diseases called peroxisome biogenesis disorders (PBD), which are part of a larger group of diseases known as the leukodystrophies. These are inherited conditions that damage the white matter of the brain and also affect how the body metabolizes particular substances in the blood and organ tissues. Zellweger syndrome is the most severe of the PBDs.

Zona – The zona pellucida (or zona striata in older texts) is a glycoprotein membrane surrounding the plasma membrane of an oocyte. It is a vital constitutive part of the latter, external but not extraneous to it.