Rapidly progressive necrotizing pneumonia: remember the Streptococcus anginosus group!

Acute necrotizing pneumonia in an immunocompetent host is uncommon and usually caused by Staphylococcus aureus infection. Streptococcus anginosus group (SAG) is a less recognized cause of rapidly destructive lung infection resulting in significant patient morbidity and mortality. Unlike many other bacterial infections, SAG can cross fascial planes and cause fulminant infections. Necrotizing pneumonia and lung abscesses due to SAG often fails conservative therapy with antimicrobials and requires definitive surgical intervention. Consideration of SAG as a potential etiology might help to institute definitive therapy earlier and prevent complications.