| K50 | Crohn's disease [regional enteritis] |
| K50.0 | Crohn's disease of small intestine |
| K50.00 | Crohn's disease of small intestine without complications |
| K50.01 | Crohn's disease of small intestine with complications |
| K50.011 | Crohn's disease of small intestine with rectal bleeding |
| K50.012 | Crohn's disease of small intestine with intestinal obstruction |
| K50.013 | Crohn's disease of small intestine with fistula |
| K50.014 | Crohn's disease of small intestine with abscess |
| K50.018 | Crohn's disease of small intestine with other complication |
| K50.019 | Crohn's disease of small intestine with unspecified complications |
| K50.1 | Crohn's disease of large intestine |
| K50.10 | Crohn's disease of large intestine without complications |
| K50.11 | Crohn's disease of large intestine with complications |
| K50.111 | Crohn's disease of large intestine with rectal bleeding |
| K50.112 | Crohn's disease of large intestine with intestinal obstruction |
| K50.113 | Crohn's disease of large intestine with fistula |
| K50.114 | Crohn's disease of large intestine with abscess |
| K50.118 | Crohn's disease of large intestine with other complication |
| K50.119 | Crohn's disease of large intestine with unspecified complications |
| K50.8 | Crohn's disease of both small and large intestine |
| K50.80 | Crohn's disease of both small and large intestine without complications |
| K50.81 | Crohn's disease of both small and large intestine with complications |
| K50.811 | Crohn's disease of both small and large intestine with rectal bleeding |
| K50.812 | Crohn's disease of both small and large intestine with intestinal obstruction |
| K50.813 | Crohn's disease of both small and large intestine with fistula |
| K50.814 | Crohn's disease of both small and large intestine with abscess |
| K50.818 | Crohn's disease of both small and large intestine with other complication |
| K50.819 | Crohn's disease of both small and large intestine with unspecified complications |
| K50.9 | Crohn's disease, unspecified |
| K50.90 | Crohn's disease, unspecified, without complications |
| K50.91 | Crohn's disease, unspecified, with complications |
| K50.911 | Crohn's disease, unspecified, with rectal bleeding |
| K50.912 | Crohn's disease, unspecified, with intestinal obstruction |
| K50.913 | Crohn's disease, unspecified, with fistula |
| K50.914 | Crohn's disease, unspecified, with abscess |
| K50.918 | Crohn's disease, unspecified, with other complication |
| K50.919 | Crohn's disease, unspecified, with unspecified complications |
| K51 | Ulcerative colitis |
| K51.0 | Ulcerative (chronic) pancolitis |
| K51.00 | Ulcerative (chronic) pancolitis without complications |
| K51.01 | Ulcerative (chronic) pancolitis with complications |
| K51.011 | Ulcerative (chronic) pancolitis with rectal bleeding |
| K51.012 | Ulcerative (chronic) pancolitis with intestinal obstruction |
| K51.013 | Ulcerative (chronic) pancolitis with fistula |
| K51.014 | Ulcerative (chronic) pancolitis with abscess |
| K51.018 | Ulcerative (chronic) pancolitis with other complication |
| K51.019 | Ulcerative (chronic) pancolitis with unspecified complications |
| K51.2 | Ulcerative (chronic) proctitis |
| K51.20 | Ulcerative (chronic) proctitis without complications |
| K51.21 | Ulcerative (chronic) proctitis with complications |
| K51.211 | Ulcerative (chronic) proctitis with rectal bleeding |
| K51.212 | Ulcerative (chronic) proctitis with intestinal obstruction |
| K51.213 | Ulcerative (chronic) proctitis with fistula |
| K51.214 | Ulcerative (chronic) proctitis with abscess |
| K51.218 | Ulcerative (chronic) proctitis with other complication |
| K51.219 | Ulcerative (chronic) proctitis with unspecified complications |
| K51.3 | Ulcerative (chronic) rectosigmoiditis |
| K51.30 | Ulcerative (chronic) rectosigmoiditis without complications |
| K51.31 | Ulcerative (chronic) rectosigmoiditis with complications |
| K51.311 | Ulcerative (chronic) rectosigmoiditis with rectal bleeding |
| K51.312 | Ulcerative (chronic) rectosigmoiditis with intestinal obstruction |
| K51.313 | Ulcerative (chronic) rectosigmoiditis with fistula |
| K51.314 | Ulcerative (chronic) rectosigmoiditis with abscess |
| K51.318 | Ulcerative (chronic) rectosigmoiditis with other complication |
| K51.319 | Ulcerative (chronic) rectosigmoiditis with unspecified complications |
| K51.4 | Inflammatory polyps of colon |
| K51.40 | Inflammatory polyps of colon without complications |
| K51.41 | Inflammatory polyps of colon with complications |
| K51.411 | Inflammatory polyps of colon with rectal bleeding |
| K51.412 | Inflammatory polyps of colon with intestinal obstruction |
| K51.413 | Inflammatory polyps of colon with fistula |
| K51.414 | Inflammatory polyps of colon with abscess |
| K51.418 | Inflammatory polyps of colon with other complication |
| K51.419 | Inflammatory polyps of colon with unspecified complications |
| K51.5 | Left sided colitis |
| K51.50 | Left sided colitis without complications |
| K51.51 | Left sided colitis with complications |
| K51.511 | Left sided colitis with rectal bleeding |
| K51.512 | Left sided colitis with intestinal obstruction |
| K51.513 | Left sided colitis with fistula |
| K51.514 | Left sided colitis with abscess |
| K51.518 | Left sided colitis with other complication |
| K51.519 | Left sided colitis with unspecified complications |
| K51.8 | Other ulcerative colitis |
| K51.80 | Other ulcerative colitis without complications |
| K51.81 | Other ulcerative colitis with complications |
| K51.811 | Other ulcerative colitis with rectal bleeding |
| K51.812 | Other ulcerative colitis with intestinal obstruction |
| K51.813 | Other ulcerative colitis with fistula |
| K51.814 | Other ulcerative colitis with abscess |
| K51.818 | Other ulcerative colitis with other complication |
| K51.819 | Other ulcerative colitis with unspecified complications |
| K51.9 | Ulcerative colitis, unspecified |
| K51.90 | Ulcerative colitis, unspecified, without complications |
| K51.91 | Ulcerative colitis, unspecified, with complications |
| K51.911 | Ulcerative colitis, unspecified with rectal bleeding |
| K51.912 | Ulcerative colitis, unspecified with intestinal obstruction |
| K51.913 | Ulcerative colitis, unspecified with fistula |
| K51.914 | Ulcerative colitis, unspecified with abscess |
| K51.918 | Ulcerative colitis, unspecified with other complication |
| K51.919 | Ulcerative colitis, unspecified with unspecified complications |
| K52 | Other and unspecified noninfective gastroenteritis and colitis |
| K52.0 | Gastroenteritis and colitis due to radiation |
| K52.1 | Toxic gastroenteritis and colitis |
| K52.2 | Allergic and dietetic gastroenteritis and colitis |
| K52.21 | Food protein-induced enterocolitis syndrome |
| K52.22 | Food protein-induced enteropathy |
| K52.29 | Other allergic and dietetic gastroenteritis and colitis |
| K52.3 | Indeterminate colitis |
| K52.8 | Other specified noninfective gastroenteritis and colitis |
| K52.81 | Eosinophilic gastritis or gastroenteritis |
| K52.82 | Eosinophilic colitis |
| K52.83 | Microscopic colitis |
| K52.831 | Collagenous colitis |
| K52.832 | Lymphocytic colitis |
| K52.838 | Other microscopic colitis |
| K52.839 | Microscopic colitis, unspecified |
| K52.89 | Other specified noninfective gastroenteritis and colitis |
| K52.9 | Noninfective gastroenteritis and colitis, unspecified |
| K55 | Vascular disorders of intestine |
| K55.0 | Acute vascular disorders of intestine |
| K55.01 | Acute (reversible) ischemia of small intestine |
| K55.011 | Focal (segmental) acute (reversible) ischemia of small intestine |
| K55.012 | Diffuse acute (reversible) ischemia of small intestine |
| K55.019 | Acute (reversible) ischemia of small intestine, extent unspecified |
| K55.02 | Acute infarction of small intestine |
| K55.021 | Focal (segmental) acute infarction of small intestine |
| K55.022 | Diffuse acute infarction of small intestine |
| K55.029 | Acute infarction of small intestine, extent unspecified |
| K55.03 | Acute (reversible) ischemia of large intestine |
| K55.031 | Focal (segmental) acute (reversible) ischemia of large intestine |
| K55.032 | Diffuse acute (reversible) ischemia of large intestine |
| K55.039 | Acute (reversible) ischemia of large intestine, extent unspecified |
| K55.04 | Acute infarction of large intestine |
| K55.041 | Focal (segmental) acute infarction of large intestine |
| K55.042 | Diffuse acute infarction of large intestine |
| K55.049 | Acute infarction of large intestine, extent unspecified |
| K55.05 | Acute (reversible) ischemia of intestine, part unspecified |
| K55.051 | Focal (segmental) acute (reversible) ischemia of intestine, part unspecified |
| K55.052 | Diffuse acute (reversible) ischemia of intestine, part unspecified |
| K55.059 | Acute (reversible) ischemia of intestine, part and extent unspecified |
| K55.06 | Acute infarction of intestine, part unspecified |
| K55.061 | Focal (segmental) acute infarction of intestine, part unspecified |
| K55.062 | Diffuse acute infarction of intestine, part unspecified |
| K55.069 | Acute infarction of intestine, part and extent unspecified |
| K55.1 | Chronic vascular disorders of intestine |
| K55.2 | Angiodysplasia of colon |
| K55.20 | Angiodysplasia of colon without hemorrhage |
| K55.21 | Angiodysplasia of colon with hemorrhage |
| K55.3 | Necrotizing enterocolitis |
| K55.30 | Necrotizing enterocolitis, unspecified |
| K55.31 | Stage 1 necrotizing enterocolitis |
| K55.32 | Stage 2 necrotizing enterocolitis |
| K55.33 | Stage 3 necrotizing enterocolitis |
| K55.8 | Other vascular disorders of intestine |
| K55.9 | Vascular disorder of intestine, unspecified |
| K56 | Paralytic ileus and intestinal obstruction without hernia |
| K56.0 | Paralytic ileus |
| K56.1 | Intussusception |
| K56.2 | Volvulus |
| K56.3 | Gallstone ileus |
| K56.4 | Other impaction of intestine |
| K56.41 | Fecal impaction |
| K56.49 | Other impaction of intestine |
| K56.5 | Intestinal adhesions [bands] with obstruction (postinfection) |
| K56.50 | Intestinal adhesions [bands], unspecified as to partial versus complete obstruction |
| K56.51 | Intestinal adhesions [bands], with partial obstruction |
| K56.52 | Intestinal adhesions [bands] with complete obstruction |
| K56.6 | Other and unspecified intestinal obstruction |
| K56.60 | Unspecified intestinal obstruction |
| K56.600 | Partial intestinal obstruction, unspecified as to cause |
| K56.601 | Complete intestinal obstruction, unspecified as to cause |
| K56.609 | Unspecified intestinal obstruction, unspecified as to partial versus complete obstruction |
| K56.69 | Other intestinal obstruction |
| K56.690 | Other partial intestinal obstruction |
| K56.691 | Other complete intestinal obstruction |
| K56.699 | Other intestinal obstruction unspecified as to partial versus complete obstruction |
| K56.7 | Ileus, unspecified |
| K57 | Diverticular disease of intestine |
| K57.0 | Diverticulitis of small intestine with perforation and abscess |
| K57.00 | Diverticulitis of small intestine with perforation and abscess without bleeding |
| K57.01 | Diverticulitis of small intestine with perforation and abscess with bleeding |
| K57.1 | Diverticular disease of small intestine without perforation or abscess |
| K57.10 | Diverticulosis of small intestine without perforation or abscess without bleeding |
| K57.11 | Diverticulosis of small intestine without perforation or abscess with bleeding |
| K57.12 | Diverticulitis of small intestine without perforation or abscess without bleeding |
| K57.13 | Diverticulitis of small intestine without perforation or abscess with bleeding |
| K57.2 | Diverticulitis of large intestine with perforation and abscess |
| K57.20 | Diverticulitis of large intestine with perforation and abscess without bleeding |
| K57.21 | Diverticulitis of large intestine with perforation and abscess with bleeding |
| K57.3 | Diverticular disease of large intestine without perforation or abscess |
| K57.30 | Diverticulosis of large intestine without perforation or abscess without bleeding |
| K57.31 | Diverticulosis of large intestine without perforation or abscess with bleeding |
| K57.32 | Diverticulitis of large intestine without perforation or abscess without bleeding |
| K57.33 | Diverticulitis of large intestine without perforation or abscess with bleeding |
| K57.4 | Diverticulitis of both small and large intestine with perforation and abscess |
| K57.40 | Diverticulitis of both small and large intestine with perforation and abscess without bleeding |
| K57.41 | Diverticulitis of both small and large intestine with perforation and abscess with bleeding |
| K57.5 | Diverticular disease of both small and large intestine without perforation or abscess |
| K57.50 | Diverticulosis of both small and large intestine without perforation or abscess without bleeding |
| K57.51 | Diverticulosis of both small and large intestine without perforation or abscess with bleeding |
| K57.52 | Diverticulitis of both small and large intestine without perforation or abscess without bleeding |
| K57.53 | Diverticulitis of both small and large intestine without perforation or abscess with bleeding |
| K57.8 | Diverticulitis of intestine, part unspecified, with perforation and abscess |
| K57.80 | Diverticulitis of intestine, part unspecified, with perforation and abscess without bleeding |
| K57.81 | Diverticulitis of intestine, part unspecified, with perforation and abscess with bleeding |
| K57.9 | Diverticular disease of intestine, part unspecified, without perforation or abscess |
| K57.90 | Diverticulosis of intestine, part unspecified, without perforation or abscess without bleeding |
| K57.91 | Diverticulosis of intestine, part unspecified, without perforation or abscess with bleeding |
| K57.92 | Diverticulitis of intestine, part unspecified, without perforation or abscess without bleeding |
| K57.93 | Diverticulitis of intestine, part unspecified, without perforation or abscess with bleeding |
| K58 | Irritable bowel syndrome |
| K58.0 | Irritable bowel syndrome with diarrhea |
| K58.1 | Irritable bowel syndrome with constipation |
| K58.2 | Mixed irritable bowel syndrome |
| K58.8 | Other irritable bowel syndrome |
| K58.9 | Irritable bowel syndrome without diarrhea |
| K59 | Other functional intestinal disorders |
| K59.0 | Constipation |
| K59.00 | Constipation, unspecified |
| K59.01 | Slow transit constipation |
| K59.02 | Outlet dysfunction constipation |
| K59.03 | Drug induced constipation |
| K59.04 | Chronic idiopathic constipation |
| K59.09 | Other constipation |
| K59.1 | Functional diarrhea |
| K59.2 | Neurogenic bowel, not elsewhere classified |
| K59.3 | Megacolon, not elsewhere classified |
| K59.31 | Toxic megacolon |
| K59.39 | Other megacolon |
| K59.4 | Anal spasm |
| K59.8 | Other specified functional intestinal disorders |
| K59.81 | Ogilvie syndrome |
| K59.89 | Other specified functional intestinal disorders |
| K59.9 | Functional intestinal disorder, unspecified |