Bi-Institutional analysis of microbiological spectrum and surgical therapy of parotid abscesses – a retrospective study

A parotid abscess (PA) is a complication of an acute bacterial parotitis with a potentially life-threatening course. Data on the diagnosis and therapy of PA is sparse. We aimed at comprehensively analyzing the microbiological spectrum and therapeutic management. We retrospectively identified all patients surgically treated for PA at two tertiary care centers in Germany. Data on demographics, clinical management and microbiology were analyzed for their statistical association with complications and recurrence. Overall, 85 patients with PA were included. Most patients (92.9%) underwent surgical incision and drainage. Approximately half of the patients (45.9%) were treated under local anesthesia (LA). The most frequently detected pathogens were Streptococci (n=23). Most patients (68.2%) received an aminopenicillin+/- beta-lactamase inhibitor as empiric antibiotic therapy. In 7 cases the antibiotic therapy was modified after receiving the antibiogram. Etiology was either idiopathic (42.4%) or obstructive, immunosuppressive, tumorous (each 11.8%). Patients with a dental focus (p=0.007) and patients with an inserted wound drain had a longer duration of hospital stay (p=0.005). Patients without drain insertion did not show a higher rate of complications (p=0.379) or recurrences (p=0.605). Chronic parotitis was significantly associated with the risk of recurrence of the PA (p<0.001). The results show that the surgical therapy of PA under LA seems to be safe. A benefit of drain insertion cannot be proven. A dental examination should routinely be performed in case of PA to rule out a dental focus. Obtaining a microbiological specimen in order to modify antibiotic therapy if necessary and obtaining a histopathological specimen to rule out a tumorous etiology is obligate.