MHC-II Deficiency Among Egyptians: Novel Mutations and Unique Phenotypes.
Rabab E El Hawary1, Andrea A Mauracher2, Safa S Meshaal1
1Clinical Pathology Department, Faculty of Medicine, Cairo University, Cairo, Egypt.
The Journal of Allergy and Clinical Immunology. in Practice
|September 1, 2018
Summary
MHC class II deficiency, a cause of combined immunodeficiency, presents unique genetic mutations in Egypt. Early diagnosis is crucial due to distinct molecular defects and potential vaccine complications.
Area of Science:
- Immunology
- Genetics
- Pediatrics
Background:
- MHC class II deficiency impairs CD4+ T-cell function due to defective antigen presentation.
- This genetic disorder, affecting one of four genes, leads to a combined immunodeficiency phenotype.
Observation:
- This study details 10 Egyptian patients with MHC class II deficiency from 2012-2017.
- Clinical presentations included failure to thrive, diarrhea, and pneumonia.
- Vaccine complications were noted, with three patients developing acute flaccid paralysis after oral polio vaccine.
Findings:
- Genetic analysis revealed mutations in RFXANK, RFX5, and CIITA genes.
- Six novel mutations were identified, highlighting genetic diversity in the Egyptian population.
- No RFXAP gene mutations were found in this cohort.
Implications:
- MHC class II deficiency is prevalent in Egypt, influenced by high consanguinity rates.
- Molecular defects in Egyptian patients differ from those in neighboring regions.
- Early clinical and laboratory diagnosis is essential, as neonatal screening may miss this condition.
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