At a Glance Systemic lupus erythematosus (SLE) is an autoimmune multisystem disease that is characterized by the presence of several autoantibodies, formation of immune complexes (ICs), and inflammation in several organs. SLE symptoms may develop slowly over months or years, or they may appear suddenly. They are widely based on the involvement of several organ…
At a Glance Severe combined immunodeficiency (SCID) is a primary immunodeficiency caused by a heterogeneous group of genetic conditions that affect the immune system, resulting in severe T- and B-lymphocyte dysfunction. It is usually detected in neonates as a failure to thrive, leading to severe weight loss and malnutrition. Affected children are often susceptible to…
At a Glance Adenosine deaminase (ADA) deficiency is an autosomal recessive systemic purine metabolic disorder that affects lymphocyte development and function. It is caused by mutations in the ADA gene and, based on their variability, can present in various clinical forms. The most severe phenotype is the severe combined immunodeficiency (SCID). It is usually evident…
At a Glance IgG subclass deficiency is defined as the decrease of one or more subclasses of IgG antibodies with normal or near normal levels of other immunoglobulin classes. It can present as either as a complete deficiency in instances in which the serum level of a IgG subclass are below detection or as a…
At a Glance Autosomal agammaglobulinemia is a disease characterized by a complete absence of B lymphocytes and complete lack of immunoglobulins. Affected individuals have frequent infections of the respiratory and digestive tracts, which typically begin after the first 6 months of life, when the maternal IgG disappears from circulation. Typical causative agents are encapsulated bacteria…
At a Glance X-linked agammaglobulinemia (XLA) is a disease characterized by absence of B lymphoocytes and marked reduction of all classes of serum immunoglobulins. Affected individuals are males with frequent infections of the respiratory and digestive tracts, which typically begin after the first 6 months of life, when the maternal IgG disappears from circulation. Typical…
At a Glance Acute rheumatic fever (ARF) is a noninfective autoimmune sequelae of pharyngitis caused by group A beta-hemolytic streptococcus. ARF mainly affects children 6-15 years of age. Symptoms usually appear 2-3 weeks after the initial infection. This latent period is rarely shorter than 1 week or longer than 5 weeks. ARF symptoms very between…
At a Glance Systemic sclerosis (SSc) is a systemic connective tissue disease of unknown etiology that affects the skin, blood vessels, muscles, joints, and a variety of internal organs, such as the digestive tract, heart, lungs, and kidneys. The major characteristics of this disease are immunologic abnormalities, vascular damage, and excessive diffuse fibrosis. Often, the…
At a Glance Sjogren’s syndrome (SS) is a systemic autoimmune disease that initially affects lacrimal and salivary glands, resulting in keratoconjunctivitis sicca (dry eye disease) and/or stomatitis sicca (dry mouth disease), and that can later involve a variety of systemic manifestations. The disease may be isolated (primary SS) or it may occur in association with…
