Perianal Abscess Recurrence and Fistula Formation: Antibiotics Following Incision and Drainage Trial
Status:
Recruiting
Trial end date:
2023-02-28
Target enrollment:
Participant gender:
Summary
Most perianal abscesses (PA) result from an infection originating in anal crypts that extend
into anal glands in the intersphincteric plane. Patients commonly present to the ER and
usually require surgical intervention, which poses a burden on the healthcare system. If left
undrained, a PA can expand into the adjacent tissues as well as progress to systemic
infection. One of the major complications of PA are perianal fistulae; the creation of a
tract between the anal canal and the perianal skin that is lined with granulation tissue or
skin cells. Up to 1/3 of patients with a PA will develop a fistula; which occurs if a PA
drains spontaneously through the perianal skin, and the infection becomes chronic. If this
happens, surgical intervention is needed and abscesses may reoccur. Post incision and
drainage (I&D) antibiotics in PA have been used to address complications but their use is
still controversial and there are no specific recommendations on their use to prevent the
formations of fistulae.
Recent findings from a systematic review (6 studies, N=817 patients) published in 2019
demonstrated that antibiotic use following I&D of PA was associated with a 36% lower odds of
fistula formation, though the quality of the evidence was low.
As there are no established prophylactic treatments for fistulae, and because they are
difficult to treat, further study of this simple intervention seems warranted. In this trial,
adults with a PA requiring I&D will be randomly assigned to receive standard of care with
antibiotics or standard of care without antibiotics after I&D. This trial will be conducted
under the IMPACTS (Innovative, Multicentre, Patient-centred Approach to Clinical Trials in
Surgery) program umbrella and will follow IMPACTS methodology. For the Vanguard trial, the
aim is to determine the feasibility of conducting a definitive trial. Future outcomes of
interest are incidence of fistula formation (defined as drainage of the perianal region at or
after 2 months), need for re-intervention (i.e., any intervention on the perianal region),
quality of life, healthcare utilization, healing time and mortality.