Gastrointestinal People with<unk>  usually present with diarrhea mixed with blood, of gradual onset that persists for an extended period of time (weeks). Additional symptoms may include fecal incontinence, increased frequency of bowel movements, mucus discharge, and nocturnal defecations. With proctitis (inflammation of the rectum), people with<unk>  may experience urgency or rectal tenesmus, which is the urgent desire to evacuate the bowels but with the passage of little stool. Tenesmus may be misinterpreted as constipation, due to the urge to defecate despite small volume of stool passage. Bloody diarrhea and abdominal pain may be more prominent features in severe disease. The severity of abdominal pain with<unk>  varies from mild discomfort to very painful bowel movements and abdominal cramping. High frequency of bowel movements, weight loss, nausea, fatigue, and fever are also common during disease flares. Chronic bleeding from the GI tract, chronic inflammation, and iron deficiency often leads to anemia, which can affect quality of life. The clinical presentation of<unk>  depends on the extent of the disease process. Up to 15% of individuals may have severe disease upon initial onset of symptoms. A substantial proportion (up to 45%) of people with a history of<unk>  without any ongoing symptoms (clinical remission) have objective evidence of ongoing inflammation.<unk>  is associated with a generalized inflammatory process that can affect many parts of the body. Sometimes, these associated extra-intestinal symptoms are the initial signs of the disease. Extent of involvement Classification of colitis, often used in defining the extent of involvement of<unk> , with proctitis (blue), proctosigmoiditis (yellow), left sided colitis (orange) and pancolitis (red). All classes extend distally to the end of the rectum. Gross pathology of normal colon (left) and severe<unk>  (right), forming pseudopolyps (smaller than the cobblestoning typically seen in Crohn's disease), over a continuous area (rather than skip lesions of Crohn's disease), and with a relatively gradual transition from normal colon (while Crohn's is typically more abrupt). In contrast to Crohn's disease, which can affect areas of the gastrointestinal tract outside of the colon,<unk>  is usually confined to the colon. Inflammation in<unk>  is usually continuous, typically involving the rectum, with involvement extending proximally (to sigmoid colon, ascending colon, etc). In contrast, inflammation with Crohn's disease is often patchy, with so-called "skip lesions." The disease is classified by the extent of involvement, depending on how far the disease extends: proctitis (rectal inflammation), left sided colitis (inflammation extending to descending colon), and extensive colitis (inflammation proximal to the descending colon). Proctosigmoiditis describes inflammation of the rectum and sigmoid colon. Pancolitis describes involvement of the entire colon, extending from the rectum to the cecum. While usually associated with Crohn's disease, ileitis (inflammation of the ileum) also occurs in<unk> . About 17% of individuals with<unk>  have ileitis. Ileitis more commonly occurs in the setting of pancolitis (occurring in 20% of cases of pancolitis), and tends to correlate with the activity of colitis. This so-called "backwash ileitis" can occur in 10–20% of people with pancolitis and is believed to be of little clinical significance. Severity of disease In addition to the extent of involvement,<unk>  is also characterized by severity of disease. Severity of disease is defined by symptoms, objective markers of inflammation (endoscopic findings, blood tests), disease course, and the impact of the disease on day-to-day life. Mild disease correlates with fewer than four stools daily; in addition, mild urgency and rectal bleeding may occur intermittently. Mild disease lacks systemic signs of toxicity, and exhibits normal levels of serum inflammatory markers (erythrocyte sedimentation rate and C-reactive protein). Moderate to severe disease correlates with more than six stools daily, frequent bloody stools and urgency. Moderate abdominal pain, low-grade fever, , and anemia may develop (75% of normal). Toxicity is present, as demonstrated by fever, tachycardia, anemia or an elevated ESR or CRP. Fulminant disease correlates with more than 10 bowel movements daily, continuous bleeding, toxicity, abdominal tenderness and distension, blood transfusion requirement, and colonic dilation (expansion). People with fulminant<unk>  may have inflammation extending beyond just the mucosal layer, causing impaired colonic motility and leading to toxic megacolon. If the serous membrane is involved, a colonic perforation may ensue.<unk>  may improve and enter remission. Remission of disease is characterized by formed stools, the absence of bloody diarrhea, resolution of urgency, and normal levels of serum inflammatory markers. Extraintestinal manifestations and complications Aphthous ulcers involving the tongue, lips, palate, and pharynx. Pyoderma gangrenosum with large ulcerations affecting the back.<unk>  is characterized by immune dysregulation and systemic inflammation, which may result in symptoms and complications outside the colon. Commonly affected organs include: eyes, joints, skin, and liver. The frequency of such extraintestinal manifestations has been reported as between 6 and 47%.<unk>  may affect the mouth. About 8% of individuals with<unk>  develop oral manifestations. The two most common oral manifestations are aphthous stomatitis and angular cheilitis. Aphthous stomatitis is characterized by ulcers in the mouth, which are benign, noncontagious and often recurrent. Angular chelitis is characterized by redness at the corners of the mouth, which may include painful sores or breaks in the skin. Very rarely, benign pustules may occur in the mouth (pyostomatitis vegetans).<unk>  may affect the eyes. Inflammation may occur in the interior portion of the eye, leading to uveitis and iritis. Uveitis can cause blurred vision and eye pain, especially when exposed to light (photophobia). Untreated, uveitis can lead to permanent vision loss. Inflammation may also involve the white part of the eye (sclera) or the overlying connective tissue (episclera), causing conditions called scleritis and episcleritis. Uveitis and iritis are more commonly associated with<unk> , whereas episcleritis is more commonly associated with Crohn's disease.<unk>  may cause several joint manifestations, including a type of rheumatologic disease known as seronegative arthritis, which may affect few large joints (oligoarthritis), the vertebra (ankylosing spondylitis) or several small joints of the hands and feet (peripheral arthritis). Often the insertion site where muscle attaches to bone (entheses) becomes inflamed (enthesitis). Inflammation may affect the sacroiliac joint (sacroiliitis). The symptoms of arthritis include joint pain, swelling, and effusion, and often leads to significant morbidity.<unk>  may affect the skin. The most common type of skin manifestation, erythema nodosum, presents as raised, tender red nodules usually appearing on the shins. Erythema nodosum is due to inflammation of the underlying subcutaneous tissue (panniculitis). A more severe skin manifestation, pyoderma gangrenosum, is characterized painful pustules or nodules that become ulcers which progressively grow. Whereas erythema nodosum tends correlate with the activity of the<unk>  and often improves with treatment of the colonic inflammation, pyoderma gangrenosum may occur independently of<unk>  disease activity. In some cases, pyoderma gangrenosum may require injection with corticosteroids.<unk>  may affect the blood and endocrine system.<unk>  increases the risk of blood clots; painful swelling of the lower legs can be a sign of deep venous thrombosis, while difficulty breathing may be a result of pulmonary embolism (blood clots in the lungs). The risk of blood clots is about three fold higher in individuals with IBD. The risk of venous thromboembolism is high in<unk>  due to hypercoagulability from inflammation, especially with active or extensive disease. Additional risk factors may include surgery, hospitalization, pregnancy, the use of corticosteroids and tofacitinib. The immune system may attack the red blood cells, leading to autoimmune hemolytic anemia. In addition to autoimmune destruction, anemia may occur due to chronic blood loss from rectal bleeding and bone marrow suppression due to inflammation (anemia of chronic disease). Osteoporosis may occur related to systemic inflammation, which increases the risk of bone fractures. Clubbing, a deformity of the ends of the fingers, may occur. Amyloidosis may occur, especially with severe and poorly controlled disease, which usually presents with protein in the urine (proteinuria) and nephritic syndrome. Primary sclerosing cholangitis<unk>  has a significant association with primary sclerosing cholangitis (PSC), a progressive inflammatory disorder of small and large bile ducts. Up to 70-90% of people with primary sclerosing cholangitis have<unk> . As many as 5% of people with<unk>  may progress to develop primary sclerosing cholangitis. PSC is more common in men, and often onsets between 30 and 40 years of age. In some cases, primary sclerosing cholangitis occurs several years before the bowel symptoms of<unk>  develop. PSC does not parallel the onset, extent, duration, or activity of the colonic inflammation in<unk> . In addition, colectomy does not have an impact on the course of primary sclerosing cholangitis in individuals with<unk> . PSC is associated with an increased risk of colorectal cancer and cholangiocarcinoma (bile duct cancer). PSC is a progressive condition, and may result in cirrhosis of the liver. No specific therapy has been proven to affect the long term course of PSC.
Ulcerative colitis
Crohn's disease
Diversion colitis
Dysentery
Collagenous colitis
Ischemic colitis
Microscopic colitis
Chemical colitis