Complement deficiency

From IDWiki

Background

  • Group of primary or acquired immunodeficiencies affecting the complement system within the innate humoural immune system
  • Usually autosomal recessive genetic diseases
  • Commonly defined as early (C1-C4) or late (C5-C9)

Clinical Manifestations

Deficiency
Early (C1, C2, and C4) Encapsulated bacterial infections like Streptococcus pneumoniae and Haemophilus influenzae type b. Higher risk of autoimmune diseases, particularly systemic lupus erythematosus)
Early (C3) Severe recurrent pyogenic infections early in life
Late (C5-C9) Recurrent Neisseria infections
Alternative (properdin) Recurrent Neisseria infections
Mannan-binding lectin Increase frequency of pyogenic infections, particularly in young children