The Veneto region's database of hospital discharge records was queried for ICD-9 codes corresponding to: peritonsillar abscess (PTA), PTA incision and drainage, tonsillectomy, pharyngeal-retropharyngeal abscess, cervical phlegmon, cervical abscess, and mediastinitis recorded from 1997 to 2006. All these codes were considered to identify cases of PTA recurrence and severe infectious complications occurring in conservatively treated patients. Among 4,199 patients whose PTA was incised and drained on admission to hospital, 1,532 were treated with tonsillectomy, while 2,667 were treated conservatively (without tonsillectomy). Abscess tonsillectomy was carried out almost exclusively in children (0-14 years of age), and only in 40 young and adult patients (0.95 %). The relapse rate after a single episode of PTA was 11.7 %, while potentially fatal complication occurred in 0.41 % of cases. Incidence of PTA hospital admission has remained stable in the considered period despite a 45 % reduction in the tonsillectomy rate. In conclusion, our data seem to show that conservative treatment for PTA is not associated with a significant risk of recurrence (and becomes minimal after 6-12 months), provided that patients have not suffered from previous PTA episodes.
Keywords: Deep neck infection; Mediastinitis; Peritonsillar abscess; Pharyngeal abscess; Surgery; Tonsils.