Superinfection

Second infection on top of a previous one

A superinfection is a second infection superimposed on an earlier one, especially by a different microbial agent of exogenous or endogenous origin, that is resistant to the treatment being used against the first infection. Examples of this in bacteriology are the overgrowth of endogenous Clostridium difficile that occurs following treatment with a broad-spectrum antibiotic, and pneumonia or sepsis from Pseudomonas aeruginosa in some immunocompromised patients.

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