Colorectal Quiz Episode 26: Perianal Crohn's Disease
In pediatric patients, unlike adult patients, the first presenting factor for Crohn's disease can often be perianal disease.
Male gender over the age of 10, and presence of a fistula are risk factors with much higher incidence of Crohn's disease being diagnosed in patients presenting with perianal lesions to the emergency room.
The mucosa heals first compared to skin in perianal disease, so leaving a mucosal opening without a seton risks recurrent abscess when biologics heal the mucosa.
Making a large cruciate incision and packing a perianal abscess in a child with undiagnosed Crohn's disease may result in non-healing and potentially require colostomy or ileostomy.
The highest risk factors for lymphoma with biologic therapy are male gender, teenage age, and combination therapy with methotrexate.
Real risks of biologic agents include infectious complications such as tuberculosis and risk of lymphoma.
When the colonoscope cannot intubate the terminal ileum, capsule endoscopy or fecal calprotectin can be used to aid diagnosis.
If terminal ileum cannot be intubated, gastroenterologists may treat presumptively and re-scope after a few months of treatment when inflammation has decreased.
Setons should remain in place for at least 6 months to allow the inflammatory tract to become non-inflammatory.
Before removing a seton, the bottom must look better, drainage must be better, the patient must be symptom-free, and they must have reached steady state of biologic (loading dose plus at least 3 more doses, typically 2-3 months from start).
Inflammatory markers including fecal calprotectin, ESR, and CRP should be checked before removing a seton to ensure systemic disease is under control.
The initial Remicade paper from 1998 or 1999 in the New England Journal of Medicine was on perianal disease and demonstrated improved healing time and improved length of time between recurrence when combination of seton and infliximab is used versus either separately.
Remicade (infliximab) has the most literature on healing perianal disease; Humira also has good evidence but less literature; Stelara and vedolizumab are sometimes used with less information available.
Literature shows about a 10% response rate for perianal fistulas even without biologics if a seton is placed and removed, with much better outcomes with biologics.
Source control of infection must be achieved before starting immunosuppressive therapy including steroids and biologics.
If an abscess is not adequately drained, reimaging should be performed before giving biologics or steroids.
Hydrogen peroxide is preferred over methylene blue for identifying fistula tracts because it is neater; 3% hydrogen peroxide in a syringe with 16-20 gauge angiocath is used with a speculum in the anus.
When a fistula opening cannot be found despite hydrogen peroxide testing, a seton should not be placed at that time to avoid creating a hole where there isn't one.
For recurrent patients requiring repeat seton placement, repeat imaging should be obtained before seton removal.
It is common to have perianal disease in Crohn's; this patient had a delay in diagnosis and had perianal disease for quite some time with multiple skin tags and fissures.
Journal of Pediatric Surgery Article Review: May 2023, CAPS Issue
The Hirschsprung-associated IBD study was a retrospective study from 2000 to 2021 at 17 institutions with 55 patients.
Host summaryCecilia Gigena summarizing the discussion — not the host's own clinical position1:33
50% of Hirschsprung-associated IBD patients had long segment disease.
Host summaryCecilia Gigena summarizing the discussion — not the host's own clinical position2:05
Enterocolitis was reported in 68% of Hirschsprung patients after pull-through.
Host summaryCecilia Gigena summarizing the discussion — not the host's own clinical position2:05
The most common presentation for Hirschsprung-associated IBD was colonic or small bowel inflammation resembling IBD.
Host summaryCecilia Gigena summarizing the discussion — not the host's own clinical position2:17
Three risk factors for Hirschsprung-associated IBD are trisomy 21, a history of enterocolitis following pull-through surgery, and long segment disease.
Biologic therapy is most likely to be effective for treating Hirschsprung-associated IBD.
Hirschsprung's associated IBD is very poorly defined, presents in a number of different ways, and the reason why it happens is unknown.
Hirschsprung's enterocolitis that persists past age 5, or that is unresponsive to typical treatment under age 5, should prompt consideration of Hirschsprung-associated IBD diagnosis.
The COVID-19 appendicitis study assessed patients from February 2018 to June 2019 (pre-pandemic control) and mid-February 2020 to June 2021 (COVID period).
Host summaryEm Tombash summarizing the discussion — not the host's own clinical position4:32
The study included 1100 patients total: 44% in pre-pandemic control group and 56% in COVID-19 group.
Host summaryEm Tombash summarizing the discussion — not the host's own clinical position4:55