Insights

The complement system, a key human biological amplification system, can cause autoimmune disorders or infections when deficient. This review details complement component deficiencies, their clinical signs, and lab evaluation methods.

Area of Science:

  • Immunology
  • Human Biology

Context:

  • The complement system is a critical component of innate immunity.
  • Deficiencies in complement components are linked to significant health issues.

Purpose:

  • To review the clinical manifestations and pathophysiology of known complement component deficiencies.
  • To outline laboratory evaluation procedures for suspected complement deficiency.

Summary:

  • Hereditary deficiencies in complement components can result in autoimmune diseases, recurrent bacterial infections, or non-atopic cutaneous edema.
  • This review consolidates current knowledge on the clinical presentation and underlying mechanisms of these deficiencies.
  • Diagnostic laboratory evaluation protocols are presented for affected individuals.

Impact:

  • Enhances understanding of complement system's role in health and disease.
  • Provides a clinical and diagnostic guide for healthcare professionals managing complement deficiencies.
  • Aids in the early identification and management of patients with recurrent infections or autoimmune conditions.

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