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Published on: January 19, 2014
[H Factor Deficiency: A Case with an Atypical Presentation]
Ana Paula Rocha1, Madalena Borges1, Conceição Neves1
1Unidade de Imunodeficiências Primárias. Serviço de Pediatria. Hospital Dona Estefânia. Centro Hospitalar Lisboa Central. Lisboa. Portugal.
Insights
H factor deficiency, typically causing infections and kidney issues, presented atypically in a child with ear infections. Family history of autoimmune disorders aided diagnosis, highlighting unusual presentations of this complement system disorder.
Area of Science:
- Immunology
- Genetics
- Pediatrics
Background:
- H factor deficiency is a rare disorder affecting the complement system, typically presenting with Neisseria meningitidis infections and renal disease.
- Atypical presentations can occur, making diagnosis challenging.
Abstract:
We report a case of an 18-month-old boy with H factor deficiency with atypical presentation: recurrent acute otitis media and several maternal family members with autoimmune disorders (vitiligo, thyroiditis and immune trombocytopenia). Blood tests revealed low C3 and AH50, as well as low properdin and H factor. I factor was normal. CFH gene molecular test confirmed the H factor deficiency diagnosis. This child had none of the typical manifestations of this disorder, namely Neisseria meningitidis infection or renal disease (glomerulonephritis and atypical haemolytic uremic syndrome). Autoimmune family history and correct interpretation of blood tests' results were crucial for this diagnosis.
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