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| Cytomegalovirus colitis | |
|---|---|
| Other names | CMV colitis |
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| Micrograph of CMV colitis. H&E stain. | |
| Specialty | Infectious diseases |
Cytomegalovirus colitis (CMV colitis) is an inflammation of the colon.
The infection is spread by saliva, urine, respiratory droplets, sexual contact, and blood transfusions. Most people are exposed to the virus in their lifetime, but it usually produces mild or no symptoms in healthy people.[ citation needed ]
However, serious CMV infections can occur in people with weakened immune systems. This includes patients receiving chemotherapy for cancer and patients on immune-suppressing medicines following an organ transplant.[ citation needed ]
In rare instances, more severe CMV infection involving the gastrointestinal tract has been reported in people with a healthy immune system.[ citation needed ]
The systemic use of corticosteroids in the context of inflammatory bowel disease can promote CMV infection in the colon. [1] The corticosteroids used as a primary treatment for flare-up events of inflammatory bowel disease reduce the autoimmune activity of the T lymphocytes and monocytes that contribute to the inflammation of the colon and small intestine. By inhibiting the function of these leukocytes, corticosteroids reduce the inflammation caused by IBD, but this immunosuppression enables CMV to infect the colon. [2] Similarly, use of the immunosuppressive drug that is required to decrease risk of rejection in patients who received transplant as Liver transplantation or Kidney transplantation is a risk factor for CMV infection. [3]
CMV colitis may be clinically manifested with diarrhea (usually non-bloody), abdominal pain, weight loss and anorexia. The diagnosis of CMV colitis is based on serology, CMV antigen testing and colonoscopy with biopsy. Clinical suspicion should be aroused in the setting of immunocompromised patient but it is much rarer in immunocompetent patient. Although it is known that CMV colitis is almost always caused by reactivation of latent CMV infection in immunocompromised patients, new infection of CMV or reinfection of different strain of CMV can cause colitis in immunocompetent hosts. Because asymptomatic CMV viremia and viruria is common and about 1/3 of symptomatic CMV infection is caused by reinfection of different strain of CMV, the diagnosis of CMV colitis needs more direct causality. It is practically achieved by colonoscopy or sigmoidoscopy tissue sampling and pathological evidence of CMV infection under microscope, more specifically macroscopic picture will show many ulcers that appear on the mucous membrane and microscopically the biopsy will show intranuclear and cytoplasmic inclusion bodies. Positive CMV IgG doesn't necessarily mean that it is reactivation of latent infection because of the possibility of reinfection of different strain.[ citation needed ]
The usual treatment is antivirals, specifically ganciclovir or valganciclovir. [1] Severe CMV colitis may lead a colectomy. [4]
Gastroenterology is the branch of medicine focused on the digestive system and its disorders. The digestive system consists of the gastrointestinal tract, sometimes referred to as the GI tract, which includes the esophagus, stomach, small intestine and large intestine as well as the accessory organs of digestion which include the pancreas, gallbladder, and liver.
Crohn's disease is a chronic inflammatory bowel disease characterized by recurrent episodes of intestinal inflammation, primarily manifesting as diarrhea and abdominal pain. Unlike ulcerative colitis, inflammation can occur anywhere in the gastrointestinal tract, though it most frequently affects the ileum and colon, involving all layers of the intestinal wall. Symptoms may be non-specific and progress gradually, often delaying diagnosis. About one-third of patients have colonic disease, another third have ileocolic disease, and the remaining third have isolated ileal disease. Systemic symptoms such as chronic fatigue, weight loss, and low-grade fevers are common. Organs such as the skin and joints can also be affected. Complications can include bowel obstructions, fistulas, nutrition problems, and an increased risk of intestinal cancers.
Ulcerative colitis (UC) is one of the two types of inflammatory bowel disease (IBD), with the other type being Crohn's disease. It is a long-term condition that results in inflammation and ulcers of the colon and rectum. The primary symptoms of active disease are abdominal pain and diarrhea mixed with blood (hematochezia). Weight loss, fever, and anemia may also occur. Often, symptoms come on slowly and can range from mild to severe. Symptoms typically occur intermittently with periods of no symptoms between flares. Complications may include abnormal dilation of the colon (megacolon), inflammation of the eye, joints, or liver, and colon cancer.
Immunosuppressive drugs, also known as immunosuppressive agents, immunosuppressants and antirejection medications, are drugs that inhibit or prevent the activity of the immune system.
Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine, as well as the mouth, esophagus, stomach and the anus, whereas UC primarily affects the colon and the rectum.
Colitis is swelling or inflammation of the large intestine (colon). Colitis may be acute and self-limited or long-term. It broadly fits into the category of digestive diseases.
Toxic megacolon is an acute form of colonic distension. It is characterized by a very dilated colon (megacolon), accompanied by abdominal distension (bloating), and sometimes fever, abdominal pain, or shock.
Diverticular disease is when problems occur due to diverticulosis, a benign condition defined by the formation of pouches (diverticula) from weak spots in the wall of the large intestine. This disease spectrum includes diverticulitis, symptomatic uncomplicated diverticular disease (SUDD), and segmental colitis associated with diverticulosis (SCAD). The most common symptoms across the disease spectrum are abdominal pain and bowel habit changes such as diarrhea or constipation. Otherwise, diverticulitis presents with systemic symptoms such as fever and elevated white blood cell count whereas SUDD and SCAD do not. Treatment ranges from conservative bowel rest to medications such as antibiotics, antispasmodics, acetaminophen, mesalamine, rifaximin, and corticosteroids depending on the specific conditions.
Megacolon is an abnormal dilation of the colon. This leads to hypertrophy of the colon. The dilation is often accompanied by a paralysis of the peristaltic movements of the bowel. In more extreme cases, the feces consolidate into hard masses inside the colon, called fecalomas, which can require surgery to be removed.
Blood in stool looks different depending on how early it enters the digestive tract—and thus how much digestive action it has been exposed to—and how much there is. The term can refer either to melena, with a black appearance, typically originating from upper gastrointestinal bleeding; or to hematochezia, with a red color, typically originating from lower gastrointestinal bleeding. Evaluation of the blood found in stool depends on its characteristics, in terms of color, quantity and other features, which can point to its source, however, more serious conditions can present with a mixed picture, or with the form of bleeding that is found in another section of the tract. The term "blood in stool" is usually only used to describe visible blood, and not fecal occult blood, which is found only after physical examination and chemical laboratory testing.
Pouchitis is an umbrella term for inflammation of the ileal pouch, an artificial rectum surgically created out of ileum in patients who have undergone a proctocolectomy or total colectomy. The ileal pouch-anal anastomosis is created in the management of patients with ulcerative colitis, indeterminate colitis, familial adenomatous polyposis, cancer, or rarely, other colitides.
Immune reconstitution inflammatory syndrome (IRIS) is a condition seen in some cases of HIV/AIDS or immunosuppression, in which the immune system begins to recover, but then responds to a previously acquired opportunistic infection with an overwhelming inflammatory response that paradoxically makes the symptoms of infection worse.
Management of ulcerative colitis involves first treating the acute symptoms of the disease, then maintaining remission. Ulcerative colitis is a form of colitis, a disease of the intestine, specifically the large intestine or colon, that includes characteristic ulcers, or open sores, in the colon. The main symptom of active disease is usually diarrhea mixed with blood, of gradual onset which often leads to anaemia. Ulcerative colitis is, however, a systemic disease that affects many parts of the body outside the intestine.
Biological therapy, the use of medications called biopharmaceuticals or biologics that are tailored to specifically target an immune or genetic mediator of disease, plays a major role in the treatment of inflammatory bowel disease. Even for diseases of unknown cause, molecules that are involved in the disease process have been identified, and can be targeted for biological therapy. Many of these molecules, which are mainly cytokines, are directly involved in the immune system. Biological therapy has found a niche in the management of cancer, autoimmune diseases, and diseases of unknown cause that result in symptoms due to immune related mechanisms.
Human betaherpesvirus 5, also called human cytomegalovirus (HCMV,HHV-5), is a species of virus in the genus Cytomegalovirus, which in turn is a member of the viral family known as Herpesviridae or herpesviruses. It is also commonly called CMV. Within Herpesviridae, HCMV belongs to the Betaherpesvirinae subfamily, which also includes cytomegaloviruses from other mammals. CMV is a double-stranded DNA virus.
Pancolitis or universal colitis, in its most general sense, refers to inflammation of the entire large intestine comprising the cecum, ascending, transverse, descending, sigmoid colon and rectum. It can be caused by a variety of things such as inflammatory bowel disease, more specifically a severe form of ulcerative colitis. A diagnosis can be made using a number of techniques but the most accurate method is direct visualization via a colonoscopy. Symptoms are similar to those of ulcerative colitis but more severe and affect the entire large intestine. Patients generally exhibit symptoms including rectal bleeding as a result of ulcers, pain in the abdominal region, inflammation in varying degrees, and diarrhea, fatigue, fever, and night sweats. Due to the loss of function in the large intestine patients may lose large amounts of weight from being unable to procure nutrients from food. In other cases the blood loss from ulcers can result in anemia which can be treated with iron supplements. Additionally, due to the chronic nature of most cases of pancolitis, patients have a higher chance of developing colorectal cancer.
Colonic ulcer can occur at any age, in children however they are rare. Most common symptoms are abdominal pain and hematochezia.
Checkpoint inhibitor induced colitis is an inflammatory condition affecting the colon (colitis), which is caused by cancer immunotherapy. Symptoms typically consist of diarrhea, abdominal pain and rectal bleeding. Less commonly, nausea and vomiting may occur, which may suggest the present of gastroenteritis. The severity of diarrhea and colitis are graded based on the frequency of bowel movements and symptoms of colitis, respectively.
Segmental colitis associated with diverticulosis (SCAD) is a condition characterized by localized inflammation in the colon, which spares the rectum and is associated with multiple sac-like protrusions or pouches in the wall of the colon (diverticulosis). Unlike diverticulitis, SCAD involves inflammation of the colon between diverticula, while sparing the diverticular orifices. SCAD may lead to abdominal pain, especially in the left lower quadrant, intermittent rectal bleeding and chronic diarrhea.
Shomron Ben-Horin is an Israeli physician, a co-founder & Chief Medical Officer of Evinature, and professor of medicine at the Tel-Aviv University.