holy fuck, what causes such a thing??
For centuries, the diagnosis and treatment of deep neck space infections have challenged physicians and surgeons. The complexity and the deep location of this region make diagnosis and treatment of infections in this area difficult. These infections remain an important health problem with significant risks of morbidity and mortality.
Deep neck space infections, including parapharyngeal abscess, peritonsillar abscess, and retropharyngeal abscess, commonly originate from an odontogenic or oropharyngeal infection and generally are polymicrobial, involving aerobic and anaerobic bacteria from the primary source. These infections may be life threatening, and initial empiric antimicrobial therapy should include broad coverage for beta-lactamase-producing bacteria, including Staphylococcus aureus, Streptococcus pyogenes, anaerobic gram-negative bacilli, and Peptostreptococcus species.
http://emedicine.medscape.com/article/2014986-overview 
