Lymphocytic Colitis
05.08.10
Lymphocytic colitis, a subtype of microscopic colitis, is a rare condition characterized by chronic non-bloody watery diarrhea. The colonoscopy is normal but the mucosal biopsy reveals an accumulation of lymphocytes in the colonic epithelium and connective tissue (lamina propria).
No definite etiology has been determined. Some reports have implicated long-term usage of NSAIDs, antidepressants, and other drugs; and overactive immune responses are also suspected. Over-the-counter antidiarrheal drugs are effective for many people with lymphocytic colitis. Anti-inflammatory drugs, such as salicylates may also help.
Corticosteroids or Mesalazines may be prescribed for people who do not respond to other drug treatment. The long-term prognosis for this disease is not clear. Lymphocytic colitis is closely related to collagenous colitis. Both are characterized by a syndrome of watery diarrhea, usually occurring in young to middle aged women. The etiology is unknown but an autoimmune basis has long been suspected.
However, an infectious etiology has not been excluded. In favor of an infectious etiology are cases associated with an outbreak of Brainerd diarrhea aboard a cruise ship. Brainerd diarrhea has been applied to cases of diarrhea of unknown etiology with an acute onset and prolonged duration.
Like collagenous colitis, a chronic watery diarrhea is present, but this lasts longer than 6 months and frequently for many years. Biopsies show similar features to lymphocytic colitis except there may a lesser degree of lymphocytic infiltration. lymphocytic colitis, is considered now an important cause of diarrhea in middle aged and elderly patients.
In this entity, endoscopic and radiological examinations are normal while specific histological findings are seen on colonic biopsy. Once the diagnosis of MC is confirmed, a stepwise approach with medical therapy is suggested. Ruling out other causes of chronic diarrhea should be the initial step. Once the diagnosis of MC is confirmed, a stepwise treatment algorithm is suggested.
In this review, I will introduce the entity of MC and describe the stepwise approach to diagnosis and management by reviewing the available evidence. The literature was reviewed regarding both collagenous colitis and lymphocystic colitits focusing on clinical trails. This was then critically examined and an approach to the diagnosis and management of microscopic colitis was suggested. there is inflammation in the lamina propria of the colonic mucosa, with increased intraepithelial lymphocytes.
Specifically in CC and not in LC, there is, in addition, marked thickening of the sub-epithelial collagen layer, which is the hallmark of this disease. This disease entity has attracted a lot of attention recently as an important and relatively common cause of chronic diarrhea.
The initial description of MC was first published in 1976 and since that time, it has been increasingly recognized as a relatively common cause of chronic diarrhea.