Other diseases of intestines (K55-K64)
K55Vascular disorders of intestine
Excludes 1: necrotizing enterocolitis of newborn (P77.-)
Excludes 2: angioectasia (angiodysplasia) duodenum (K31.81-)
K55.0Acute vascular disorders of intestine
› Infarction of appendices epiploicae
› Mesenteric (artery) (vein) embolism
› Mesenteric (artery) (vein) infarction
› Mesenteric (artery) (vein) thrombosis
K55.01Acute (reversible) ischemia of small intestine
K55.011Focal (segmental) acute (reversible) ischemia of small intestine
K55.012Diffuse acute (reversible) ischemia of small intestine
K55.019Acute (reversible) ischemia of small intestine, extent unspecified
K55.02Acute infarction of small intestine
› Gangrene of small intestine
› Necrosis of small intestine
K55.021Focal (segmental) acute infarction of small intestine
K55.022Diffuse acute infarction of small intestine
K55.029Acute infarction of small intestine, extent unspecified
K55.03Acute (reversible) ischemia of large intestine
› Acute fulminant ischemic colitis
› Subacute ischemic colitis
K55.031Focal (segmental) acute (reversible) ischemia of large intestine
K55.032Diffuse acute (reversible) ischemia of large intestine
K55.039Acute (reversible) ischemia of large intestine, extent unspecified
K55.04Acute infarction of large intestine
› Gangrene of large intestine
› Necrosis of large intestine
K55.041Focal (segmental) acute infarction of large intestine
K55.042Diffuse acute infarction of large intestine
K55.049Acute infarction of large intestine, extent unspecified
K55.05Acute (reversible) ischemia of intestine, part unspecified
K55.051Focal (segmental) acute (reversible) ischemia of intestine, part unspecified
K55.052Diffuse acute (reversible) ischemia of intestine, part unspecified
K55.059Acute (reversible) ischemia of intestine, part and extent unspecified
K55.06Acute infarction of intestine, part unspecified
› Acute intestinal infarction
› Gangrene of intestine
› Necrosis of intestine
K55.061Focal (segmental) acute infarction of intestine, part unspecified
K55.062Diffuse acute infarction of intestine, part unspecified
K55.069Acute infarction of intestine, part and extent unspecified
K55.1Chronic vascular disorders of intestine
› Chronic ischemic colitis
› Chronic ischemic enteritis
› Chronic ischemic enterocolitis
› Ischemic stricture of intestine
› Mesenteric atherosclerosis
› Mesenteric vascular insufficiency
K55.2Angiodysplasia of colon
K55.20Angiodysplasia of colon without hemorrhage
K55.21Angiodysplasia of colon with hemorrhage
K55.3Necrotizing enterocolitis
Excludes 1: necrotizing enterocolitis of newborn (P77.-)
Excludes 2: necrotizing enterocolitis due to Clostridium difficile (A04.7-)
K55.30Necrotizing enterocolitis, unspecified
› Necrotizing enterocolitis, NOS
K55.31Stage 1 necrotizing enterocolitis
› Necrotizing enterocolitis without pneumatosis, without perforation
K55.32Stage 2 necrotizing enterocolitis
› Necrotizing enterocolitis with pneumatosis, without perforation
K55.33Stage 3 necrotizing enterocolitis
› Necrotizing enterocolitis with perforation
› Necrotizing enterocolitis with pneumatosis and perforation
K55.8Other vascular disorders of intestine
K55.9Vascular disorder of intestine, unspecified
› Ischemic colitis
› Ischemic enteritis
› Ischemic enterocolitis
K56Paralytic ileus and intestinal obstruction without hernia
Excludes 1: congenital stricture or stenosis of intestine (Q41-Q42)
› cystic fibrosis with meconium ileus (E84.11)
› ischemic stricture of intestine (K55.1)
› meconium ileus NOS (P76.0)
› neonatal intestinal obstructions classifiable to P76.-
› obstruction of duodenum (K31.5)
› postprocedural intestinal obstruction (K91.3-)
Excludes 2: stenosis of anus or rectum (K62.4)
K56.0Paralytic ileus
› Paralysis of bowel
› Paralysis of colon
› Paralysis of intestine
Excludes 1: gallstone ileus (K56.3)
› ileus NOS (K56.7)
› obstructive ileus NOS (K56.69-)
K56.1Intussusception
› Intussusception or invagination of bowel
› Intussusception or invagination of colon
› Intussusception or invagination of intestine
› Intussusception or invagination of rectum
Excludes 2: intussusception of appendix (K38.8)
K56.2Volvulus
› Strangulation of colon or intestine
› Torsion of colon or intestine
› Twist of colon or intestine
Excludes 2: volvulus of duodenum (K31.5)
K56.3Gallstone ileus
› Obstruction of intestine by gallstone
K56.4Other impaction of intestine
K56.41Fecal impaction
Excludes 1: constipation (K59.0-)
Excludes 2: incomplete defecation (R15.0)
K56.49Other impaction of intestine
K56.5Intestinal adhesions [bands] with obstruction (postinfection)
› Abdominal hernia due to adhesions with obstruction
› Peritoneal adhesions [bands] with intestinal obstruction (postinfection)
K56.50Intestinal adhesions [bands], unspecified as to partial versus complete obstruction
› Intestinal adhesions with obstruction NOS
K56.51Intestinal adhesions [bands], with partial obstruction
› Intestinal adhesions with incomplete obstruction
K56.52Intestinal adhesions [bands] with complete obstruction
K56.6Other and unspecified intestinal obstruction
K56.60Unspecified intestinal obstruction
K56.600Partial intestinal obstruction, unspecified as to cause
› Incomplete intestinal obstruction, NOS
K56.601Complete intestinal obstruction, unspecified as to cause
K56.609Unspecified intestinal obstruction, unspecified as to partial versus complete obstruction
› Intestinal obstruction NOS
K56.69Other intestinal obstruction
› Enterostenosis NOS
› Obstructive ileus NOS
› Occlusion of colon or intestine NOS
› Stenosis of colon or intestine NOS
› Stricture of colon or intestine NOS
K56.690Other partial intestinal obstruction
› Other incomplete intestinal obstruction
K56.691Other complete intestinal obstruction
K56.699Other intestinal obstruction unspecified as to partial versus complete obstruction
› Other intestinal obstruction, NEC
K56.7Ileus, unspecified
Excludes 1: obstructive ileus (K56.69-)
Excludes 2: intestinal obstruction with hernia (K40-K46)
K57Diverticular disease of intestine
Code Also: if applicable peritonitis K65.-
Excludes 1: congenital diverticulum of intestine (Q43.8)
› Meckel's diverticulum (Q43.0)
Excludes 2: diverticulum of appendix (K38.2)
K57.0Diverticulitis of small intestine with perforation and abscess
Excludes 1: diverticulitis of both small and large intestine with perforation and abscess (K57.4-)
K57.00Diverticulitis of small intestine with perforation and abscess without bleeding
K57.01Diverticulitis of small intestine with perforation and abscess with bleeding
K57.1Diverticular disease of small intestine without perforation or abscess
Excludes 1: diverticular disease of both small and large intestine without perforation or abscess (K57.5-)
K57.10Diverticulosis of small intestine without perforation or abscess without bleeding
› Diverticular disease of small intestine NOS
K57.11Diverticulosis of small intestine without perforation or abscess with bleeding
K57.12Diverticulitis of small intestine without perforation or abscess without bleeding
K57.13Diverticulitis of small intestine without perforation or abscess with bleeding
K57.2Diverticulitis of large intestine with perforation and abscess
Excludes 1: diverticulitis of both small and large intestine with perforation and abscess (K57.4-)
K57.20Diverticulitis of large intestine with perforation and abscess without bleeding
K57.21Diverticulitis of large intestine with perforation and abscess with bleeding
K57.3Diverticular disease of large intestine without perforation or abscess
Excludes 1: diverticular disease of both small and large intestine without perforation or abscess (K57.5-)
K57.30Diverticulosis of large intestine without perforation or abscess without bleeding
› Diverticular disease of colon NOS
K57.31Diverticulosis of large intestine without perforation or abscess with bleeding
K57.32Diverticulitis of large intestine without perforation or abscess without bleeding
K57.33Diverticulitis of large intestine without perforation or abscess with bleeding
K57.4Diverticulitis of both small and large intestine with perforation and abscess
K57.40Diverticulitis of both small and large intestine with perforation and abscess without bleeding
K57.41Diverticulitis of both small and large intestine with perforation and abscess with bleeding
K57.5Diverticular disease of both small and large intestine without perforation or abscess
K57.50Diverticulosis of both small and large intestine without perforation or abscess without bleeding
› Diverticular disease of both small and large intestine NOS
K57.51Diverticulosis of both small and large intestine without perforation or abscess with bleeding
K57.52Diverticulitis of both small and large intestine without perforation or abscess without bleeding
K57.53Diverticulitis of both small and large intestine without perforation or abscess with bleeding
K57.8Diverticulitis of intestine, part unspecified, with perforation and abscess
K57.80Diverticulitis of intestine, part unspecified, with perforation and abscess without bleeding
K57.81Diverticulitis of intestine, part unspecified, with perforation and abscess with bleeding
K57.9Diverticular disease of intestine, part unspecified, without perforation or abscess
K57.90Diverticulosis of intestine, part unspecified, without perforation or abscess without bleeding
› Diverticular disease of intestine NOS
K57.91Diverticulosis of intestine, part unspecified, without perforation or abscess with bleeding
K57.92Diverticulitis of intestine, part unspecified, without perforation or abscess without bleeding
K57.93Diverticulitis of intestine, part unspecified, without perforation or abscess with bleeding
K58Irritable bowel syndrome
Includes: irritable colon
› spastic colon
K58.0Irritable bowel syndrome with diarrhea
K58.1Irritable bowel syndrome with constipation
K58.2Mixed irritable bowel syndrome
K58.8Other irritable bowel syndrome
K58.9Irritable bowel syndrome without diarrhea
› Irritable bowel syndrome NOS
K59Other functional intestinal disorders
Excludes 1: change in bowel habit NOS (R19.4)
› intestinal malabsorption (K90.-)
› psychogenic intestinal disorders (F45.8)
Excludes 2: functional disorders of stomach (K31.-)
K59.0Constipation
Excludes 1: fecal impaction (K56.41)
Excludes 2: incomplete defecation (R15.0)
K59.00Constipation, unspecified
K59.01Slow transit constipation
K59.02Outlet dysfunction constipation
K59.03Drug induced constipation
Use Additional Code: code for adverse effect, if applicable, to identify drug (T36-T50) with fifth or sixth character 5)
K59.04Chronic idiopathic constipation
› Functional constipation
K59.09Other constipation
› Chronic constipation
K59.1Functional diarrhea
Excludes 1: diarrhea NOS (R19.7)
› irritable bowel syndrome with diarrhea (K58.0)
K59.2Neurogenic bowel, not elsewhere classified
K59.3Megacolon, not elsewhere classified
› Dilatation of colon
Code First: , if applicable (T51-T65) to identify toxic agent
Excludes 1: congenital megacolon (aganglionic) (Q43.1)
› megacolon (due to) (in) Chagas' disease (B57.32)
› megacolon (due to) (in) Clostridium difficile (A04.7-)
› megacolon (due to) (in) Hirschsprung's disease (Q43.1)
K59.31Toxic megacolon
K59.39Other megacolon
› Megacolon NOS
K59.4Anal spasm
› Proctalgia fugax
K59.8Other specified functional intestinal disorders
K59.81Ogilvie syndrome
› Acute colonic pseudo-obstruction (ACPO)
K59.89Other specified functional intestinal disorders
› Atony of colon
› Pseudo-obstruction (acute) (chronic) of intestine
K59.9Functional intestinal disorder, unspecified
K60Fissure and fistula of anal and rectal regions
Excludes 1: fissure and fistula of anal and rectal regions with abscess or cellulitis (K61.-)
Excludes 2: anal sphincter tear (healed) (nontraumatic) (old) (K62.81)
K60.0Acute anal fissure
K60.1Chronic anal fissure
K60.2Anal fissure, unspecified
K60.3Anal fistula
K60.4Rectal fistula
› Fistula of rectum to skin
Excludes 1: rectovaginal fistula (N82.3)
› vesicorectal fistual (N32.1)
K60.5Anorectal fistula
K61Abscess of anal and rectal regions
Includes: abscess of anal and rectal regions
› cellulitis of anal and rectal regions
K61.0Anal abscess
› Perianal abscess
Excludes 2: intrasphincteric abscess (K61.4)
K61.1Rectal abscess
› Perirectal abscess
Excludes 1: ischiorectal abscess (K61.39)
K61.2Anorectal abscess
K61.3Ischiorectal abscess
K61.31Horseshoe abscess
K61.39Other ischiorectal abscess
› Abscess of ischiorectal fossa
› Ischiorectal abscess, NOS
K61.4Intrasphincteric abscess
› Intersphincteric abscess
K61.5Supralevator abscess
K62Other diseases of anus and rectum
Includes: anal canal
Excludes 2: colostomy and enterostomy malfunction (K94.0-, K94.1-)
› fecal incontinence (R15.-)
› hemorrhoids (K64.-)
K62.0Anal polyp
K62.1Rectal polyp
Excludes 1: adenomatous polyp (D12.8)
K62.2Anal prolapse
› Prolapse of anal canal
K62.3Rectal prolapse
› Prolapse of rectal mucosa
K62.4Stenosis of anus and rectum
› Stricture of anus (sphincter)
K62.5Hemorrhage of anus and rectum
Excludes 1: gastrointestinal bleeding NOS (K92.2)
› melena (K92.1)
› neonatal rectal hemorrhage (P54.2)
K62.6Ulcer of anus and rectum
› Solitary ulcer of anus and rectum
› Stercoral ulcer of anus and rectum
Excludes 1: fissure and fistula of anus and rectum (K60.-)
› ulcerative colitis (K51.-)
K62.7Radiation proctitis
Use Additional Code: code to identify the type of radiation (W88.-)
› or radiation therapy (Y84.2)
K62.8Other specified diseases of anus and rectum
Excludes 2: ulcerative proctitis (K51.2)
K62.81Anal sphincter tear (healed) (nontraumatic) (old)
› Tear of anus, nontraumatic
Use Additional Code: code for any associated fecal incontinence (R15.-)
Excludes 2: anal fissure (K60.-)
› anal sphincter tear (healed) (old) complicating delivery (O34.7-)
› traumatic tear of anal sphincter (S31.831)
K62.82Dysplasia of anus
› Anal intraepithelial neoplasia I and II (AIN I and II) (histologically confirmed)
› Dysplasia of anus NOS
› Mild and moderate dysplasia of anus (histologically confirmed)
Excludes 1: abnormal results from anal cytologic examination without histologic confirmation (R85.61-)
› anal intraepithelial neoplasia III (D01.3)
› carcinoma in situ of anus (D01.3)
› HGSIL of anus (R85.613)
› severe dysplasia of anus (D01.3)
K62.89Other specified diseases of anus and rectum
› Proctitis NOS
Use Additional Code: code for any associated fecal incontinence (R15.-)
K62.9Disease of anus and rectum, unspecified
K63Other diseases of intestine
K63.0Abscess of intestine
Excludes 1: abscess of intestine with Crohn's disease (K50.014, K50.114, K50.814, K50.914,)
› abscess of intestine with diverticular disease (K57.0, K57.2, K57.4, K57.8)
› abscess of intestine with ulcerative colitis (K51.014, K51.214, K51.314, K51.414, K51.514, K51.814, K51.914)
Excludes 2: abscess of anal and rectal regions (K61.-)
› abscess of appendix (K35.3-)
K63.1Perforation of intestine (nontraumatic)
› Perforation (nontraumatic) of rectum
Excludes 1: perforation (nontraumatic) of duodenum (K26.-)
› perforation (nontraumatic) of intestine with diverticular disease (K57.0, K57.2, K57.4, K57.8)
Excludes 2: perforation (nontraumatic) of appendix (K35.2-, K35.3-)
K63.2Fistula of intestine
Excludes 1: fistula of duodenum (K31.6)
› fistula of intestine with Crohn's disease (K50.013, K50.113, K50.813, K50.913,)
› fistula of intestine with ulcerative colitis (K51.013, K51.213, K51.313, K51.413, K51.513, K51.813, K51.913)
Excludes 2: fistula of anal and rectal regions (K60.-)
› fistula of appendix (K38.3)
› intestinal-genital fistula, female (N82.2-N82.4)
› vesicointestinal fistula (N32.1)
K63.3Ulcer of intestine
› Primary ulcer of small intestine
Excludes 1: duodenal ulcer (K26.-)
› gastrointestinal ulcer (K28.-)
› gastrojejunal ulcer (K28.-)
› jejunal ulcer (K28.-)
› peptic ulcer, site unspecified (K27.-)
› ulcer of intestine with perforation (K63.1)
› ulcer of anus or rectum (K62.6)
› ulcerative colitis (K51.-)
K63.4Enteroptosis
K63.5Polyp of colon
Excludes 2: adenomatous polyp of colon (D12.-)
› inflammatory polyp of colon (K51.4-)
› polyposis of colon (D12.6)
K63.8Other specified diseases of intestine
K63.81Dieulafoy lesion of intestine
Excludes 2: Dieulafoy lesion of stomach and duodenum (K31.82)
K63.82Intestinal microbial overgrowth
K63.821Small intestinal bacterial overgrowth
K63.8211Small intestinal bacterial overgrowth, hydrogen-subtype
K63.8212Small intestinal bacterial overgrowth, hydrogen sulfide-subtype
K63.8219Small intestinal bacterial overgrowth, unspecified
K63.822Small intestinal fungal overgrowth
K63.829Intestinal methanogen overgrowth, unspecified
K63.89Other specified diseases of intestine
K63.9Disease of intestine, unspecified
K64Hemorrhoids and perianal venous thrombosis
Includes: piles
Excludes 1: hemorrhoids complicating childbirth and the puerperium (O87.2)
› hemorrhoids complicating pregnancy (O22.4)
K64.0First degree hemorrhoids
› Grade/stage I hemorrhoids
› Hemorrhoids (bleeding) without prolapse outside of anal canal
K64.1Second degree hemorrhoids
› Grade/stage II hemorrhoids
› Hemorrhoids (bleeding) that prolapse with straining, but retract spontaneously
K64.2Third degree hemorrhoids
› Grade/stage III hemorrhoids
› Hemorrhoids (bleeding) that prolapse with straining and require manual replacement back inside anal canal
K64.3Fourth degree hemorrhoids
› Grade/stage IV hemorrhoids
› Hemorrhoids (bleeding) with prolapsed tissue that cannot be manually replaced
K64.4Residual hemorrhoidal skin tags
› External hemorrhoids, NOS
› Skin tags of anus
K64.5Perianal venous thrombosis
› External hemorrhoids with thrombosis
› Perianal hematoma
› Thrombosed hemorrhoids NOS
K64.8Other hemorrhoids
› Internal hemorrhoids, without mention of degree
› Prolapsed hemorrhoids, degree not specified
K64.9Unspecified hemorrhoids
› Hemorrhoids (bleeding) NOS
› Hemorrhoids (bleeding) without mention of degree