K61.31 Horseshoe abscess

Billable ICD-10-CM code, FY2026.

Applies from K61 Abscess of anal and rectal regions

Includes

• abscess of anal and rectal regions
• cellulitis of anal and rectal regions

MS-DRG index

Defines the logic of DRG(s) 393-395 in MDC 06.

Code annotations containing back-references to K61.31

Back-references to K61

• Type 1 Excludes: K60 Fissure and fistula of anal and rectal regions ("fissure and fistula of anal and rectal regions with abscess or cellulitis (K61.-)")
• Type 2 Excludes: K60 Fissure and fistula of anal and rectal regions ("abscess or cellulitis of anal and rectal regions (K61.-)")
• Type 2 Excludes: K63.0 Abscess of intestine ("abscess of anal and rectal regions (K61.-)")
• Type 2 Excludes: L02 Cutaneous abscess, furuncle and carbuncle ("abscess of anus and rectal regions (K61.-)")
• Type 2 Excludes: L03 Cellulitis and acute lymphangitis ("cellulitis of anal and rectal region (K61.-)")
• Type 2 Excludes: L03.31 Cellulitis of trunk ("cellulitis of anal and rectal regions (K61.-)")

Diagnosis Index entries for K61.31

• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › horseshoe

Nearby codes

• K61 Abscess of anal and rectal regions
• K61.0 Anal abscess
• K61.1 Rectal abscess
• K61.2 Anorectal abscess
• K61.3 Ischiorectal abscess
• K61.31 Horseshoe abscess (this code)
• K61.39 Other ischiorectal abscess
• K61.4 Intrasphincteric abscess
• K61.5 Supralevator abscess