Introduction

As well as inflammatory bowel disease, there are a number of other conditions which either predispose to or cause perianal disease. For the most part, these are relatively simple and can be managed by a local specialist but there are cases where more nuanced approach is needed and where tertiary referral maybe more appropriate. In particular, rarer forms of perianal disease such as complex cryptoglandular fistula, rectovaginal fistula (RVF) and those associated with ileoanal pouches are associated with high levels of morbidity, risk and treatment failure. Experience in patient selection, multiple reparative techniques and identifying rare causes are crucial, and where evidence is lacking, this experience is the surgeon’s only weapon.

The Association of Coloproctology of Great Britain and Ireland have recently released an updated position statement on anal fistula, once again recognising its complexity and often a lack of high-level evidence for treatment.1 A greater proportion of men suffer from anorectal abscess than women and these occur at a mean age of 40 in both sexes.2–4 Known risk factors associated with developing an abscess include inflammatory bowel disease (IBD), smoking and HIV.5 The most commonly reported symptoms are pain and discharge, causing social embarrassment and loss of quality of life (QoL).6–9

It is thought that approximately 90% of abscesses occur due to cryptoglandular suppuration, with infection of the intersphincteric anal glands which lubricate the passage of stool.10 11 The remaining ~10% of cases are caused by Crohn’s disease (CD), abdominal infections tracking caudally (eg, diverticulitis), penetrative causes (eg, animal bones or by anal digitation),12 perforated cancers (eg, rectal or anal) or post radiotherapy, penetrating ulcers,13 tuberculosis (TB),14 actinomycosis15 or from a complication of local surgical procedures (eg, haemorrhoidectomy, episiotomy) or medical treatment (with nicorandil, which causes perianal or peristomal ulceration …