ICD-10-CM > K00-K95 > K55-K64 > K60 > K60.5 K60.5 Anorectal fistula Non-Billable/Non-Specific Code First , if applicable:Crohn's disease (K50.-)ulcerative colitis (K51.-) Type 1 Excludes congenital fistula (Q43.6) Codes K60.50Anorectal fistula, unspecifiedK60.51Anorectal fistula, simpleK60.511Anorectal fistula, simple, initialK60.512Anorectal fistula, simple, persistentK60.513Anorectal fistula, simple, recurrentK60.519Anorectal fistula, simple, unspecifiedK60.52Anorectal fistula, complexK60.521Anorectal fistula, complex, initialK60.522Anorectal fistula, complex, persistentK60.523Anorectal fistula, complex, recurrentK60.529Anorectal fistula, complex, unspecified