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Complement Deficiency Syndromes
Complement deficiency is an immunodeficiency of absent or suboptimal functioning of one of the complement system proteins. Because of redundancies in the immune system, many complement disorders are never diagnosed. Some studies estimate that less than 10% are identified. ''Hypocomplementemia'' may be used more generally to refer to decreased complement levels, while ''secondary complement disorder'' means decreased complement levels that are not directly due to a genetic cause but secondary to another medical condition. Signs and symptoms The following symptoms (signs) are consistent with complement deficiency in general: Complications Vaccinations for encapsulated organisms (e.g., ''Neisseria meningitidis'' and ''Streptococcus pneumoniae'') is crucial for preventing infections in complement deficiencies. Among the possible complications are the following: * Deficiencies of the terminal complement components increases susceptibility to infections by ''Neisseria''. Causes The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunodeficiency
Immunodeficiency, also known as immunocompromisation, is a state in which the immune system's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that affect the patient's immune system. Examples of these extrinsic factors include HIV infection and environmental factors, such as nutrition. Immunocompromisation may also be due to genetic diseases/flaws such as SCID. In clinical settings, immunosuppression by some drugs, such as steroids, can either be an adverse effect or the intended purpose of the treatment. Examples of such use is in organ transplant surgery as an anti- rejection measure and in patients with an overactive immune system, as in autoimmune diseases. Some people are born with intrinsic defects in their immune system, or primary immunodeficiency. A person who has an immunodeficiency of any kind is said to be immunocompromised. An immunocompromised individual may particular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neisseria
''Neisseria'' is a large genus of bacteria that colonize the mucosal surfaces of many animals. Of the 11 species that colonize humans, only two are pathogens, '' N. meningitidis'' and ''N. gonorrhoeae''. ''Neisseria'' species are Gram-negative bacteria included among the Pseudomonadota, a large group of Gram-negative forms. ''Neisseria'' diplococci resemble coffee beans when viewed microscopically. Pathogenesis and classification Pathogens Species of this genus (family Neisseriaceae) of parasitic bacteria grow in pairs and occasionally tetrads, and thrive best at 98.6 °F (37 °C) in the animal body or serum media. The genus includes: * ''N. gonorrhoeae'' (also called the gonococcus) causes gonorrhea. * '' N. meningitidis'' (also called the meningococcus) is one of the most common causes of bacterial meningitis and the causative agent of meningococcal septicaemia. These two species have the ability of 'breaching' the barrier. Local cytokines of the area become secr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complement Component 4
Complement component 4 (C4), in humans, is a protein involved in the intricate complement system, originating from the human leukocyte antigen (HLA) system. It serves a number of critical functions in immunity, tolerance, and autoimmunity with the other numerous components. Furthermore, it is a crucial factor in connecting the recognition pathways of the overall system instigated by antibody-antigen (Ab-Ag) complexes to the other effector proteins of the innate immune response. For example, the severity of a dysfunctional complement system can lead to fatal diseases and infections. Complex variations of it can also lead to schizophrenia. The C4 protein was thought to derive from a simple two-locus allelic model, which however has been replaced by a much more sophisticated multimodular RCCX gene complex model which contain long and short forms of the C4A or C4B genes usually in tandem RCCX cassettes with copy number variation, that somewhat parallels variation in the levels of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complement Component 3
Complement component 3, often simply called C3, is a protein of the immune system. It plays a central role in the complement system and contributes to innate immunity. In humans it is encoded on chromosome 19 by a gene called ''C3''. Function C3 plays a central role in the activation of the complement system. Its activation is required for both classical and alternative complement activation pathways. People with C3 deficiency are susceptible to bacterial infection. One form of C3-convertase, also known as C4b2a, is formed by a heterodimer of activated forms of C4 and C2. It catalyzes the proteolytic cleavage of C3 into C3a and C3b, generated during activation through the classical pathway as well as the lectin pathway. C3a is an anaphylotoxin and the precursor of some cytokines such as ASP, and C3b serves as an opsonizing agent. Factor I can cleave C3b into C3c and C3d, the latter of which plays a role in enhancing B cell responses. In the alternative complement pathway, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systemic Lupus Erythematosus
Lupus, technically known as systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Common symptoms include painful and swollen joints, fever, chest pain, hair loss, mouth ulcers, swollen lymph nodes, feeling tired, and a red rash which is most commonly on the face. Often there are periods of illness, called flares, and periods of remission during which there are few symptoms. The cause of SLE is not clear. It is thought to involve a mixture of genetics combined with environmental factors. Among identical twins, if one is affected there is a 24% chance the other one will also develop the disease. Female sex hormones, sunlight, smoking, vitamin D deficiency, and certain infections are also believed to increase a person's risk. The mechanism involves an immune response by autoantibodies against a person's own tissues. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryoglobulinemia
Cryoglobulinemia is a medical condition in which the blood contains large amounts of pathological cold sensitive antibodies called cryoglobulins – proteins (mostly immunoglobulins themselves) that become insoluble at reduced temperatures. This should be contrasted with cold agglutinins, which cause agglutination of red blood cells. Cryoglobulins typically precipitate (clumps together) at temperatures below normal body temperatureand will dissolve again if the blood is heated. The precipitated clump can block blood vessels and cause toes and fingers to become gangrenous. While this disease is commonly referred to as cryoglobulinemia in the medical literature, it is better termed cryoglobulinemic disease for two reasons: 1) cryoglobulinemia is also used to indicate the circulation of (usually low levels of) cryoglobulins in the absence of any symptoms or disease and 2) healthy individuals can develop transient asymptomatic cryoglobulinemia following certain infections. In con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocarditis
Endocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves. Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or the surfaces of intracardiac devices. Endocarditis is characterized by lesions, known as '' vegetations'', which is a mass of platelets, fibrin, microcolonies of microorganisms, and scant inflammatory cells. In the subacute form of infective endocarditis, the vegetation may also include a center of granulomatous tissue, which may fibrose or calcify. There are several ways to classify endocarditis. The simplest classification is based on cause: either ''infective'' or ''non-infective'', depending on whether a microorganism is the source of the inflammation or not. Regardless, the diagnosis of endocarditis is based on clinical features, investigations such as an echocardiogram, and blood cultures demonstrating the presence of endocarditis-c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteomyelitis
Osteomyelitis (OM) is an infection of bone. Symptoms may include pain in a specific bone with overlying redness, fever, and weakness. The long bones of the arms and legs are most commonly involved in children e.g. the femur and humerus, while the feet, spine, and hips are most commonly involved in adults. The cause is usually a bacterial infection, but rarely can be a fungal infection. It may occur by spread from the blood or from surrounding tissue. Risks for developing osteomyelitis include diabetes, intravenous drug use, prior removal of the spleen, and trauma to the area. Diagnosis is typically suspected based on symptoms and basic laboratory tests as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR).This is because plain radiographs are unremarkable in the first few days following acute infection. Diagnosis is further confirmed by blood tests, medical imaging, or bone biopsy. Treatment of bacterial osteomyelitis often involves both antimicrobials and sur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hereditary Angioedema
Hereditary angioedema (HAE) is a disorder that results in recurrent attacks of severe swelling. The swelling most commonly affects the arms, legs, face, intestinal tract, and airway. If the intestinal tract is affected, abdominal pain and vomiting may occur. Swelling of the airway can result in its obstruction and trouble breathing. Without preventive treatment, attacks typically occur every two weeks and last for a few days. There are three main types of HAE. Types I and II are caused by a mutation in the '' SERPING1'' gene, which makes the C1 inhibitor protein, while type III is often due to a mutation in the '' F12'' (factor XII) gene. The result is increased levels of bradykinin, which promotes swelling. The condition may be inherited in an autosomal dominant manner or occur as a new mutation. Triggers for an attack may include minor trauma or stress, but attacks often occur without any obvious preceding event. Diagnosis of types I and II is based on measurement of C4 and C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Properdin Deficiency
Properdin deficiency is a rare X-linked disease in which properdin, an important Complement system, complement factor responsible for the stabilization of the alternative C3 convertase, is deficient. There are three forms of properdin deficiencies: Type I, which is identified by the total absence of the properdin protein in the plasma, Type II, which is a low but detectable amount of the properdin protein in the plasma, and Type III, which is a rare case of normal levels of properdin protein, but a dysfunctional variant. One of the first studied cases of properdin deficiency was in 1980 bDavis and Forrestal These families had members with only partial deficiencies which resulted in a lowered consumption of the Complement component 3, C3 protein. Properdin deficiency was studied again shortly after in 1982 bSjoholmin which all of the subjects were deceased shortly after the study because of their disease. The largest study of properdin deficiency was in 1989 bFijenwhich included nine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MBL Deficiency
MBL deficiency is a pathology of the innate immune system involving Mannan-binding lectin pathway The lectin pathway or lectin complement pathway is a type of cascade reaction in the complement system, similar in structure to the classical complement pathway, in that, after activation, it proceeds through the action of C4 and C2 to produce acti ... components such as MBL2. It is thought that 5–10% of the population have an MBL deficiency of some degree. There are varying degrees of MBL deficiency; some people will not even know they have the deficiency, while others may have such low levels that they experience infections with great frequency. Babies and young children are most at risk. References External links Complement deficiency {{circulatory-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-linked
Sex linked describes the sex-specific patterns of inheritance and presentation when a gene mutation (allele) is present on a sex chromosome (allosome) rather than a non-sex chromosome (autosome). In humans, these are termed X-linked recessive, X-linked dominant and Y-linked. The inheritance and presentation of all three differ depending on the sex of both the parent and the child. This makes them characteristically different from autosomal dominance and recessiveness. There are many more X-linked conditions than Y-linked conditions, since humans have several times as many genes on the X chromosome than the Y chromosome. Only females are able to be carriers for X-linked conditions; males will always be affected by any X-linked condition, since they have no second X chromosome with a healthy copy of the gene. As such, X-linked recessive conditions affect males much more commonly than females. In X-linked recessive inheritance, a son born to a carrier mother and an unaffected fath ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
