Case Report: p40 deficiency underlying pediatric-onset systemic lupus erythematosus.

Introduction: Systemic lupus erythematosus is a multi-faceted autoimmune disorder of complex etiology. Pre-pubertal onset of pediatric systemic lupus erythematosus (pSLE) is uncommon and should raise suspicion for a genetic driver of disease. Autosomal recessive p40 deficiency is a rare immunologic disorder characterized by defective but not abolished NADPH oxidase activity with residual production of reactive oxygen species (ROS) by phagocytic cells.

Biofilm-derived Legionella pneumophila evades the innate immune response in macrophages.

Legionella pneumophila, the causative agent of Legionnaire's disease, replicates in human alveolar macrophages to establish infection. There is no human-to-human transmission and the main source of infection is L. pneumophila biofilms established in air conditioners, water fountains, and hospital equipments.