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Updated: Aug 7, 2026

Visualization of Streptococcus pneumoniae within Cardiac Microlesions and Subsequent Cardiac Remodeling
Published on: April 7, 2015
[Complement factor I deficiency revealed by repeated systemic Streptococcus pneumoniae infection]
M Monfort-Gouraud1, C Vignon, A Vincens
1Service de pédiatrie, centre hospitalier intercommunal de Montfermeil-Le-Raincy, 10, avenue du Général-Leclerc, 93370 Montfermeil, France. marie.monfortgouraud@laposte.net
Abstract:
Recurrent and serious otitis media, and 2 Streptococcus pneumoniae bacteraemia episodes evoked an immune system deficiency in a 6-year-old girl. Upon investigation of the complement system, CH50 activity was moderately reduced and C4 antigen level was normal contrasting with low C3 antigen level. Factor 1 was undetectable. Factor I deficiency is rare, and its diagnosis has important practical consequences. Thanks to preventive antibiotic therapy with penicillin V and vaccinations against Neisseria meningitidis and S. pneumoniae, life expectancy and quality of this child can be significantly improved.
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