Two related cases of primary complement deficiencies

A Farhoudi1, Nasrin Bazargan, Zabra Pourpak

  • 1Immunology, Asthma and Allergy Research Institute; Children Hospital Medical Center; Tehran University of Medical Sciences, Tehran, Iran.

Insights

Two related patients with rare primary complement deficiencies, C3 deficiency and hereditary angioedema, highlight a potential genetic link between these immune disorders.

Area of Science:

  • Immunology
  • Genetics

Background:

  • Primary complement deficiencies are rare immune system disorders.
  • Two related patients presented with distinct complement deficiencies: C3 deficiency and hereditary angioedema.

Purpose of the Study:

  • To report two related cases of primary complement deficiencies.
  • To investigate a potential genetic relationship between C3 deficiency and hereditary angioedema.

Main Methods:

  • Case report of two related patients.
  • Immunological testing including serum C3, C1INH, and C4 levels.
  • Exclusion of other causes for angioedema.

Main Results:

  • Patient 1: 41-year-old male with C3 deficiency, recurrent pneumococcal meningitis, and glomerulonephritis.
  • Patient 2: 40-year-old female with low C1INH and C4 levels, experiencing recurrent angioedema, diagnosed with hereditary angioedema.
  • Both patients had normal results in other immunological tests.

Conclusions:

  • The findings suggest a possible genetic relationship between C3 deficiency and hereditary angioedema in related individuals.
  • Early diagnosis and management are crucial for patients with primary complement deficiencies.

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