Rothia mucilaginosa pneumonia in an immunocompetent patient.

Rothia mucilaginosa is a gram-postive coccus that occurs as part of the normal flora of the oropharynx and upper respiratory tract. Lower respiratory tract infections caused by this organism are rare and usually occur in immunocompromised patients. This is the case of an immunocompetent 47-year-old woman with right upper lobe pneumonia in which R.mucilaginosa was isolated in sputum and bronchial aspirate. Infections caused by this agent in the last four years in our hospital were reviewed. The most common predisposing factor was COPD with bronchiectasis. R.mucilaginosa was identified as the causative agent for pneumonia in only two cases, of which one was our case and the other was a patient with lung cancer.