Auditing the routine microbiological examination of pus swabs from uncomplicated perianal abscesses: clinical necessity or old habit?

Abstract

Background: Obtaining pus swabs from perianal abscesses after incision and drainage for subsequent microbiological analysis is traditionally performed by general surgeons. Our aim is to assess the current practice in our institution, emphasizing on whether pus swabs were sent or not, as well as to identify any associations between the revealed microbiology and the occurrence of immediate post-operative complications and re-admission rates with fistula-in-ano up to 12 months post the emergency drainage. Finally, we aimed to identify if the any members of the surgical team reviewed at any stage post-operatively the results of the microbiological examination of the obtained pus swabs and if that resulted in changes of the patient management.

Methods: We reviewed the operative findings and perioperative antimicrobial management of all patients within our institution that required surgical treatment of perianal abscesses over a 6-week period and re-assessed them after 12 months from the performed drainage, with respect to re-admission and identification of occurred fistula-in-ano.

Results: A total of 24 patients met our inclusion criteria. Pus swabs were sent in 66.7% of cases and only a third of the requested microbiology reports were reviewed by a part of the surgical team. All patients were discharged prior to the release of the microbiology results with no subsequent change in the management plan. We did not find any consistent association between the microbiology results and re-admission with perianal abscess, with or without fistula-in-ano.

Conclusions: We do not recommend routine use of pus swabs when draining perianal abscesses unless clinical concerns arise, including recurrent perianal sepsis, immuno-compromised status or extensive soft tissue necrosis, especially when these features are associated with systemic sepsis.