Diverticular disease

The signs and symptoms of diverticular disease stem from inflammation and irritation of the colonic tissues, which can manifest as: • Abdominal pain that may be persistent for days. Pain is typically located in the left lower quadrant. However, in people of Asian descent, pain is reported more on the right side. • Diarrhea • Constipation • Nausea and vomiting • Fever • Rectal bleeding ==Causes==

Diverticulitis Acute diverticulitis is thought to arise from either trauma or lack of blood flow to the existing diverticulum in the colon. • The traumatic theory proposes that a fecalith, which is a hardened fecal matter, becomes trapped in a diverticulum, leading to colonic mucosa abrasion and local inflammation. Subsequent bacterial overgrowth and infection spreads from the mucosal wall to full bowel wall, eventually leading to bowel perforation. Complicated acute diverticulitis is distinguished from uncomplicated diverticulitis by the presence of abscess or colonic perforation. Chronic smoldering diverticulitis is caused by recurrent acute diverticulitis that does not respond to medical treatment but does not progress to complications such as abscess, peritonitis, enteric fistula, or bowel obstruction. Symptomatic uncomplicated diverticular disease Similar to the diverticulitis ischemia theory above, SUDD is thought to be caused by sustained colonic contraction leading to mucosal ischemia within the diverticulum. Low grade inflammation of the colonic mucosa within the diverticulum and visceral hypersensitivity are also thought to cause SUDD. ==Risk factors==

Many risk factors contribute to the development and severity of diverticular disease, such as • Advanced age – diverticular disease typically presents in the sixth decade of life. • Colonic wall structure – points of blood vessel entry in the colonic wall are weaker and more prone to mucosal herniation. • Fiber intake – although it is widely believed that low fiber diet is associated with diverticulosis and diverticular disease, recent studies have not confirmed the association but has shown that increased fiber intake reduces diverticular disease complications. • NSAIDs and Aspirin use – these drugs have been shown to increase risk of diverticular bleeding and diverticulitis complications such as diverticular perforation. • Genetics – over 30 susceptibility loci have been identified for diverticular disease, including ARHGAP15, COLQ, and FAM155A. • Vitamin D – although the mechanism is unclear, recent studies have shown that vitamin D insufficient patients have higher risk of complicated diverticulitis. ==Diagnosis==

Diverticulitis Diverticulitis typically presents with tenderness in the left lower abdomen, fever, bowel habit changes such as constipation or diarrhea. Laboratory abnormalities include elevated white blood count and inflammatory markers (C-reactive protein and erythrocyte sedimentation rate). Imaging via computed tomography (CT) is the standard for diagnosing diverticulitis and evaluating potential complications. Histopathological features of SCAD include tumor necrosis factor alpha overexpression and absence of granuloma. Laboratory workup would return normal white blood count, negative serological markers and negative anti-Saccharomyces cerevisiae antibodies, distinguishing SCAD from autoimmune and other inflammatory bowel diseases. ==Treatment==

Diverticulitis Uncomplicated diverticulitis is generally treated conservatively with bowel rest and no antibiotics given recent studies have shown that antibiotics are likely not necessary. Complicated diverticulitis is treated with antibiotics and may require surgical interventions such as abscess drainage or fistula repair. Antibiotics should be used selectively in most cases of uncomplicated diverticulitis. However, antibiotic use is strongly advised in immunocompromised patients. Elective segmental colectomy can be considered in selective group of patients to reduce risk of recurrent diverticulitis. However, the procedure does not completely eliminate the risk of recurrence. Symptomatic uncomplicated diverticular disease Currently there is no supported effective treatment for SUDD. Anti-inflammatory agent mesalamine and non-absorbable antibiotic rifaximin might improve symptoms and prevent acute diverticulitis. Probiotics could also be used to reduce symptoms but there is currently insufficient supporting evidence. Segmental colitis associated with diverticulosis SCAD is a benign and self-limited condition that resolves on its own. In ongoing or recurrent cases, medical treatments with antibiotics, mesalamine, and corticosteroids might be required. ==References==