Complement and mannose-binding lectin 2 polymorphism in meningococcal disease
Alberto Lima Filho1, Rodrigo Carmo, Maria Cavalcanti
1Federal University of Pernambuco (UFPE), Brazil. albertodebarroslima@bol.com.br
Clinical Laboratory
|January 8, 2013
Summary
Complement deficiencies and MBL2 gene variations may predispose children to meningococcal disease. Evaluating complement function is recommended for affected individuals to understand susceptibility.
Area of Science:
- Immunology
- Pediatrics
- Genetics
Background:
- Meningococcal disease is a significant cause of childhood mortality.
- Individual susceptibility to meningococcal infections remains poorly understood.
- The complement system is crucial for innate immunity against Neisseria meningitidis.
Purpose of the Study:
- To investigate complement system deficiencies in children with prior meningococcal disease.
- To analyze Mannose-binding lectin 2 (MBL2) gene polymorphism in these patients.
Main Methods:
- Studied 40 children diagnosed with meningococcal disease.
- Quantified complement components C3, C4, and CH50.
- Genotyped the MBL2 gene for polymorphisms.
Main Results:
- Complement C4 deficiency was observed in 27.5% of patients.
- C3 and CH50 deficiencies were found in 2.5% of patients.
- MBL2 gene analysis revealed 55.3% AA, 36.8% AO, and 7.9% OO genotypes.
Conclusions:
- Complement deficiencies and MBL2 gene variants are potential risk factors for meningococcal disease.
- Assessing complement levels may be beneficial for children who have experienced meningococcal illness.
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