Hereditary angioedema (HAE) is a rare genetic disorder that affects the body's immune system and causes recurring episodes of swelling (angioedema). The two most common types of HAE are Type I and Type II, which are caused by mutations in the SERPING1 gene.

Type I HAE: This is the most common form of HAE, accounting for about 85% of cases. In Type I HAE, there is a deficiency of C1 inhibitor (C1-INH), a protein that helps regulate the immune system and prevent inflammation. As a result, levels of bradykinin, a peptide that causes blood vessels to dilate and leads to swelling, are increased. This can cause episodes of swelling in various parts of the body, including the face, hands, feet, and airways.

Type II HAE: This form of HAE is less common than Type I, accounting for about 15% of cases. In Type II HAE, there are normal or even elevated levels of C1-INH in the blood, but the protein is dysfunctional and cannot properly regulate the immune system. This also leads to increased levels of bradykinin and episodes of angioedema.

Both types of HAE can be serious and potentially life-threatening if swelling occurs in the airways and obstructs breathing. Treatment typically involves medications that help control the production of bradykinin or block its effects, as well as measures to prevent and manage symptoms during an acute attack.

Hereditary Angioedema (HAE) Type III is a rare genetic disorder characterized by recurrent episodes of severe swelling (angioedema) that can affect various parts of the body, including the hands, feet, limbs, face, and airway. Unlike HAE Types I and II, which are caused by deficiency or dysfunction of the C1 inhibitor protein, HAE Type III is associated with normal C1 inhibitor levels but increased activation of the contact system, leading to bradykinin-mediated vasodilation and increased vascular permeability.

HAE Type III primarily affects women and is often triggered by estrogen fluctuations, such as those occurring during pregnancy, menstruation, or the use of oral contraceptives. The symptoms of HAE Type III can be similar to those of HAE Types I and II but may also include abdominal pain, nausea, vomiting, and diarrhea.

It is important to note that the medical community has debated whether HAE Type III is a distinct clinical entity or a variant of other forms of HAE. Some experts consider it to be a form of acquired angioedema (AAE) rather than a hereditary disorder. Regardless, prompt diagnosis and appropriate management are essential for preventing potentially life-threatening complications, such as airway obstruction.

Hereditary angioedema (HAE) is a rare genetic disorder characterized by recurrent episodes of swelling in various parts of the body, including the face, lips, tongue, throat, hands, feet, and/or genitals. The swelling can also affect the gastrointestinal tract, causing abdominal pain, nausea, vomiting, and diarrhea.

HAE is caused by a deficiency or dysfunction of the C1 inhibitor protein, which is a part of the body's immune system that helps regulate inflammation and blood vessel dilation. As a result, people with HAE have uncontrolled activation of the complement system and increased levels of bradykinin, a potent vasodilator that causes the characteristic swelling.

There are three types of HAE: type I, type II, and type III. Type I and type II are caused by mutations in the gene that codes for the C1 inhibitor protein, resulting in low levels or dysfunctional C1 inhibitor protein. Type III is caused by a mutation in the coagulation factor XII gene, leading to overactivation of the contact system and increased bradykinin production.

HAE is an inherited disorder, typically passed down from parent to child in an autosomal dominant pattern. This means that a person has a 50% chance of inheriting the mutated gene from an affected parent and developing HAE. However, up to 25% of cases may occur spontaneously due to new mutations in the gene.

Treatment for HAE includes medications to prevent or reduce the severity and frequency of attacks, such as C1 inhibitor replacement therapy, attenuated androgens, and monoclonal antibodies against kallikrein. In addition, acute attacks can be treated with on-demand therapies, such as plasma-derived C1 inhibitor, icatibant, and ecallantide.

Angioedema is a medical condition characterized by rapid swelling of the skin, mucous membranes, and submucosal tissues. The swelling typically occurs in the face, lips, tongue, larynx, and extremities, and can also affect the gastrointestinal tract. Angioedema can be caused by a variety of factors, including allergic reactions, hereditary genetic mutations, and certain medications.

In medical terms, angioedema is defined as a self-limiting episode of localized edema in the deep dermis, subcutaneous tissue, or mucous membranes, characterized by well-circumscribed, nonpitting, nondependent swelling. The swelling can occur suddenly and may persist for up to 72 hours. In severe cases, angioedema can cause airway obstruction and be life-threatening if not treated promptly.

Angioedema can be classified into two main types: allergic or non-allergic. Allergic angioedema is caused by an immune response to an allergen, such as food, medication, or insect venom. Non-allergic angioedema can be further divided into several subtypes, including hereditary angioedema (HA), acquired angioedema (AAE), and drug-induced angioedema.

Hereditary angioedema is a rare genetic disorder caused by mutations in the C1 inhibitor gene, leading to uncontrolled activation of the complement system and increased production of bradykinin, a potent vasodilator. Acquired angioedema is similar to hereditary angioedema but occurs later in life and is associated with underlying medical conditions such as lymphoproliferative disorders or autoimmune diseases. Drug-induced angioedema can be caused by a variety of medications, including ACE inhibitors, angiotensin receptor blockers (ARBs), and nonsteroidal anti-inflammatory drugs (NSAIDs).

The diagnosis of angioedema is typically based on clinical presentation, medical history, and laboratory tests. Treatment depends on the underlying cause of the condition but may include antihistamines, corticosteroids, epinephrine, and medications that target the complement system or bradykinin pathway. In severe cases, hospitalization and intensive care may be necessary to manage airway obstruction and other complications.

The Complement C1 Inhibitor protein, also known as C1-INH, is a protein involved in the regulation of the complement system and the contact system, which are parts of the immune system. The complement system helps to eliminate pathogens (e.g., bacteria, viruses) from the body, while the contact system helps to regulate blood coagulation and inflammation.

C1-INH works by inhibiting the activation of C1, an enzyme complex that is the first component of the classical complement pathway. By inhibiting C1, C1-INH prevents the activation of downstream components of the complement system, thereby helping to regulate the immune response and prevent excessive inflammation.

Deficiencies or dysfunction in the C1-INH protein can lead to a group of genetic disorders known as C1 inhibitor deficiency disorders, which include hereditary angioedema (HAE) and acquired angioedema (AAE). These conditions are characterized by recurrent episodes of swelling in various parts of the body, such as the face, hands, feet, and airway, which can be painful and potentially life-threatening if they affect the airway.

Complement C1 Inactivator proteins are a part of the complement system, which is a group of proteins in the blood that play a crucial role in the body's immune defense system. Specifically, Complement C1 Inactivator proteins are responsible for regulating the activation of the first component of the complement system, C1.

The complement system is activated in response to the presence of foreign substances such as bacteria or viruses in the body. The activation of C1 leads to a cascade of reactions that result in the destruction of the foreign substance. However, if this process is not properly regulated, it can lead to damage to the body's own cells and tissues.

Complement C1 Inactivator proteins help to prevent this by regulating the activation of C1. They do this by binding to and inhibiting the activity of C1, preventing it from initiating the complement cascade. A deficiency in Complement C1 Inactivator proteins can lead to a condition called hereditary angioedema, which is characterized by recurrent episodes of swelling in various parts of the body.

Danazol is a synthetic, orally active androgenic steroid with antigonadotropic properties. It is used primarily in the treatment of endometriosis, fibrocystic breast disease, and hereditary angioedema. Danazol works by suppressing the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland, which in turn inhibits the growth of ovarian tissue and reduces the production of estrogen and progesterone. This leads to a decrease in the symptoms associated with endometriosis and fibrocystic breast disease. In the case of hereditary angioedema, danazol helps prevent attacks by increasing the levels of a protein called C1 esterase inhibitor, which is necessary for regulating the immune system and preventing inflammation.

The common side effects of danazol include weight gain, acne, oily skin, increased hair growth, changes in menstrual cycle, decreased breast size, deepening of the voice, and emotional lability. Rare but serious side effects may include liver damage, blood clots, and adrenal gland problems. Danazol is contraindicated in pregnancy due to its potential virilizing effects on the fetus. It should be used with caution in individuals with a history of liver disease, heart disease, or seizure disorders.

The medical definition of danazol can be summarized as follows:

Danazol (dan-a-zole)

A synthetic androgenic steroid with antigonadotropic properties, used primarily in the treatment of endometriosis, fibrocystic breast disease, and hereditary angioedema. Danazol suppresses the release of FSH and LH from the pituitary gland, inhibiting ovarian tissue growth and reducing estrogen and progesterone production. In hereditary angioedema, danazol increases C1 esterase inhibitor levels to prevent attacks. Common side effects include weight gain, acne, increased hair growth, menstrual changes, decreased breast size, deepened voice, and emotional lability. Rare but serious side effects may involve liver damage, blood clots, or adrenal gland problems. Danazol is contraindicated in pregnancy due to potential virilizing effects on the fetus and should be used with caution in individuals with a history of liver disease, heart disease, or seizure disorders.

Complement inactivating agents are substances or drugs that inhibit the complement system, which is a part of the immune system responsible for the recognition and elimination of foreign substances and microorganisms. The complement system consists of a group of proteins that work together to help eliminate pathogens from the body.

Complement inactivating agents are used in medical settings to prevent or treat various conditions associated with excessive or unwanted activation of the complement system, such as inflammation, autoimmune diseases, and transplant rejection. These agents can inhibit different components of the complement pathway, including C1 esterase inhibitors, C3 convertase inhibitors, and C5a receptor antagonists.

Examples of complement inactivating agents include eculizumab, ravulizumab, and Alexion's Ultomiris, which are monoclonal antibodies that target C5, a protein involved in the final steps of the complement pathway. These drugs have been approved for the treatment of paroxysmal nocturnal hemoglobinuria (PNH), atypical hemolytic uremic syndrome (aHUS), and other complement-mediated diseases.

Other complement inactivating agents include C1 esterase inhibitors, such as Berinert and Ruconest, which are used to treat hereditary angioedema (HAE). These drugs work by inhibiting the activation of the classical pathway of the complement system, thereby preventing the release of inflammatory mediators that can cause swelling and pain.

Overall, complement inactivating agents play an important role in the treatment of various complement-mediated diseases, helping to reduce inflammation, prevent tissue damage, and improve patient outcomes.

Stanozolol is a synthetic anabolic-androgenic steroid (AAS) derivative of dihydrotestosterone (DHT). It is commonly used in medicine for the treatment of hereditary angioedema and was formerly used to promote muscle growth in weakened or catabolic patients. Stanozolol has a high anabolic and moderate androgenic activity, with reduced estrogenic properties compared to testosterone. Its chemical formula is (17α-methyl-5α-androstano[2,3-c]pyrazol-17β-ol). It is important to note that the use of Stanozolol for performance enhancement is considered illegal and subject to severe penalties in many countries, including disqualification from sports events and criminal charges.

Pregnadienes are a class of steroid hormones that contain a unsaturated bond between the C4 and C5 positions in their steroid nucleus. They are important precursors in the biosynthesis of various sex steroids, such as progesterone and testosterone, in the human body. Pregnadienes are derived from pregnanes, which have a saturated bond at this position. The term "pregnadiene" refers to the chemical structure of these hormones, specifically their double bond at the C4-C5 position. They play a crucial role in the regulation of various physiological processes related to reproduction and sexual development.

Complement C4 is a protein that plays a crucial role in the complement system, which is a part of the immune system that helps to clear pathogens and damaged cells from the body. Complement C4 is involved in the early stages of the complement activation cascade, where it helps to identify and tag foreign or abnormal cells for destruction by other components of the immune system.

Specifically, Complement C4 can be cleaved into two smaller proteins, C4a and C4b, during the complement activation process. C4b then binds to the surface of the target cell and helps to initiate the formation of the membrane attack complex (MAC), which creates a pore in the cell membrane and leads to lysis or destruction of the target cell.

Deficiencies or mutations in the Complement C4 gene can lead to various immune disorders, including certain forms of autoimmune diseases and susceptibility to certain infections.

Kallikreins are a group of serine proteases, which are enzymes that help to break down other proteins. They are found in various tissues and body fluids, including the pancreas, kidneys, and saliva. In the body, kallikreins play important roles in several physiological processes, such as blood pressure regulation, inflammation, and fibrinolysis (the breakdown of blood clots).

There are two main types of kallikreins: tissue kallikreins and plasma kallikreins. Tissue kallikreins are primarily involved in the activation of kininogen, a protein that leads to the production of bradykinin, a potent vasodilator that helps regulate blood pressure. Plasma kallikreins, on the other hand, play a key role in the coagulation cascade by activating factors XI and XII, which ultimately lead to the formation of a blood clot.

Abnormal levels or activity of kallikreins have been implicated in various diseases, including cancer, cardiovascular disease, and inflammatory disorders. For example, some studies suggest that certain tissue kallikreins may promote tumor growth and metastasis, while others indicate that they may have protective effects against cancer. Plasma kallikreins have also been linked to the development of thrombosis (blood clots) and inflammation in cardiovascular disease.

Overall, kallikreins are important enzymes with diverse functions in the body, and their dysregulation has been associated with various pathological conditions.

Urticaria, also known as hives, is an allergic reaction that appears on the skin. It is characterized by the rapid appearance of swollen, pale red bumps or plaques (wheals) on the skin, which are often accompanied by itching, stinging, or burning sensations. These wheals can vary in size and shape, and they may change location and appear in different places over a period of hours or days. Urticaria is usually caused by an allergic reaction to food, medication, or other substances, but it can also be triggered by physical factors such as heat, cold, pressure, or exercise. The condition is generally harmless, but severe cases of urticaria may indicate a more serious underlying medical issue and should be evaluated by a healthcare professional.

Cardiac valve annuloplasty is a surgical procedure that involves repairing and reinforcing the ring-like structure (annulus) surrounding the heart valves, primarily the mitral or tricuspid valves. This procedure is often performed to correct valve leaks or regurgitation caused by various conditions such as valve disease or dilated cardiomyopathy.

During the annuloplasty procedure, the surgeon typically uses an artificial ring-like device (annuloplasty ring) made of fabric, metal, or a combination of both to reshape and stabilize the damaged annulus. The ring is sewn in place, reducing the size of the valve opening and helping the valve leaflets to coapt properly, thereby preventing valve leaks and improving heart function.

Annuloplasty can be performed as a standalone procedure or in combination with other cardiac surgeries such as valve replacement or repair. The specific technique and approach may vary depending on the individual patient's needs and the surgeon's preference.

Factor XII, also known as Hageman factor, is a protein that plays a role in the coagulation cascade, which is the series of events that leads to the formation of a blood clot. It is one of the zymogens, or inactive precursor proteins, that becomes activated and helps to trigger the coagulation process.

When Factor XII comes into contact with negatively charged surfaces, such as damaged endothelial cells or artificial surfaces like those found on medical devices, it undergoes a conformational change and becomes activated. Activated Factor XII then activates other proteins in the coagulation cascade, including Factor XI, which ultimately leads to the formation of a fibrin clot.

Deficiencies in Factor XII are generally not associated with bleeding disorders, as the coagulation cascade can still proceed through other pathways. However, excessive activation of Factor XII has been implicated in certain thrombotic disorders, such as deep vein thrombosis and disseminated intravascular coagulation (DIC).

Factor XIIa is a protease enzyme that plays a role in the coagulation cascade, which is the series of events that leads to blood clotting. It is formed when Factor XII, also known as Hageman factor, is activated by contact with negatively charged surfaces such as damaged endothelial cells or artificial surfaces like medical devices.

Once activated, Factor XIIa can activate other components of the coagulation cascade, including Factor XI, which ultimately leads to the formation of a fibrin clot. While Factor XIIa is an important part of the coagulation system, it is not essential for normal hemostasis (the process that stops bleeding) in humans, as people with deficiencies in Factor XII do not have an increased risk of bleeding. However, excessive activation of Factor XIIa has been implicated in several pathological conditions, including thrombosis and inflammation.

An encyclopedia is a comprehensive reference work containing articles on various topics, usually arranged in alphabetical order. In the context of medicine, a medical encyclopedia is a collection of articles that provide information about a wide range of medical topics, including diseases and conditions, treatments, tests, procedures, and anatomy and physiology. Medical encyclopedias may be published in print or electronic formats and are often used as a starting point for researching medical topics. They can provide reliable and accurate information on medical subjects, making them useful resources for healthcare professionals, students, and patients alike. Some well-known examples of medical encyclopedias include the Merck Manual and the Stedman's Medical Dictionary.