Kompletmentstatus

Kompletmentstatus refers to the functional state and circulating levels of the complement system in the blood. The complement system is a part of the innate immune defense, composed of a network of plasma proteins that, when activated, promote opsonization, inflammation, and lysis of microbes. Activation occurs via three pathways: classical, lectin, and alternative, converging on shared effector mechanisms.

Assessment of kompletmentstatus typically involves functional tests and component measurements. Functional assays include CH50, which assesses the integrity of the classical pathway, and AH50, which evaluates the alternative pathway. Quantitative measurements focus on individual components such as C3, C4, and sometimes C1q, C1 esterase inhibitors, factors B and D, and properdin. Results must be interpreted in the context of clinical presentation, and pre-analytical factors like sample handling can influence values.

Clinical interpretation hinges on levels and activity. Decreased complement levels can indicate consumption during active inflammation or immune complex diseases (for example, systemic lupus erythematosus) or glomerulonephritis, as well as certain infections. Inherited deficiencies of specific components can lead to increased susceptibility to infections and other immune problems. Complement testing can aid in diagnosis and monitoring but may be normal between flares or during effective treatment.

Notable conditions related to kompletmentstatus include deficiencies of C3 or C2, or deficiencies of components involved in the terminal pathway (C5–C9), which raise risk for severe infections with encapsulated bacteria, and C1 inhibitor deficiency, associated with hereditary angioedema.