COLORECTAL SURGERY BLOG

The rectum is a specialized reservoir which provides vital sensory and storage functions for the gastrointestinal system. When diseases such as inflammatory bowel disease, cancer, polyposis or congenital anomalies require the surgical removal of the rectum, an important part of the body is lost. Quite often, these disease processes occur in young patients between the ages of 30 and 45. Physical and emotional adjustments must be made to compensate for this loss. Research has been directed toward finding a suitable replacement for the surgically removed rectum. The major focus of investigation has been on the creation of a neorectum, or rectal pouch.

The anorectum is a specialized region of the gastrointestinal tract, performing sensory, storage and elimination functions. The mucosal lining in the rectum is columnar. It transitions to a squamous mucosa in the anal canal. It is richly endowed with discriminatory nerve endings to allow the body to distinguish between flatus, liquid and solid waste. While sturdy, the mucosal surfaces are vulnerable to trauma and infections. With or without an anal or rectal injury, sexually transmitted disease may be the source of considerable morbidity. While symptoms may be found in patients with normal immune systems, they are found in increasing frequency in the immunocompromised population. In patients with pre-existing systemic conditions such as AIDS or HIV, common pathogens may take on an even more ominous clinical significance. Part I of this two-part article contains a discussion of the anorectal manifestations of the most common sexually transmitted diseases.

At any given time in the United States, twenty million men and women have an active Human papillomavirus (HPV) infection. Five million new cases are diagnosed each year. These represent one third of all cases of newly diagnosed sexually transmitted infections. In addition to the morbidity of the disease itself, HPV is strongly associated with the development of squamous cell carcinoma of the anus. Hence, this ubiquitous virus has taken on a more menacing significance than simply that of an inconvenient sexually transmitted disease.

With the development of a new material and a relatively painless technique to close a perianal or perirectal fistula, it is useful to review the pathophysiology and treatment options for anal abscesses and anorectal fistulae. The new material, Surgisis®, is composed of po­­­rcine small intestinal submucosa ­rolled into a conical shape and inserted into an existing fistula (figure 1). This allows for tissue ingrowth and fistula closure.

Inflammatory bowel disease, specifically Crohn’s disease and ulcerative colitis, is thought to result from an abnormal immune regulatory process. Whereas ulcerative colitis is a mucosal inflammation confined to the colon, Crohn’s disease may involve transmural inflammation of any portion of the intestinal tract from the mouth to the anus. Non-caseating granulomas are the hallmark pathological finding in Crohn’s disease. Common symptoms such as diarrhea, abdominal pain or weight loss may be controlled using a variety of medications including antidiarrheal medications, 5-aminosalicylates, steroids, immunosuppressive agents, or anti-tumor necrosis factor antibodies.

It appears that early detection and removal of pre-malignant polyps, or frank malignancies, has resulted in an overall decreased death rate from cancers of the colon and rectum. From 1990 to 2003, the endpoint of the study period, the death rate attributable to colon and rectal cancer in men decreased 2.1% annually.

Ulcerative colitis and Crohn’s Disease are the two primary subclassifications of inflammatory bowel disease. Neither entity has a known etiology. However, abnormal immune regulation seems to play a causative role. Both Ulcerative Colitis and Crohn’s disease are thought to be autoimmune in origin. Ulcerative Colitis is defined by mucosal inflammation limited to the rectum and colon. Crohn’s Disease – may involve transmural inflammation of all layers of the bowel wall and can affect any portion of the gastrointestinal tract from the mouth to the anus.

Flatus, or gas is an expected and natural by-product of the normal functioning of the gastrointestinal tract. On average, between one half to two liters of gas are produced daily. This gas is eliminated through the anus approximately fourteen times per day.

The formation and elimination of flatus while normal, may be both uncomfortable and embarrassing and may be the source of laughter, concern or curiosity.

Approximately 150,000 new cases of colorectal cancer are diagnosed each year in the United States. It is the second leading cause of cancer mortality, resulting in almost 60,000 deaths every year.1 Cancers of the colon and rectum most commonly develop from precursor adenomatous polyps that increase in size over time.2,3 Early detection and removal of these premalignant polyps usually prevents them from developing into invasive cancer.4,5 This is the rationale behind the colorectal cancer screening recommendations from the American Cancer Society.

It is now accepted that most colon cancers originate from benign colon polyps. The cancer-to-polyp sequence is the driving force behind colon screening to find and remove polyps before they transform into a malignancy. There is a unified set of screening guidelines that address the age of first screening, the frequency of screening and the method of screening. This screening has been effective in achieving the stated goal of reducing the number of new colon malignancies detected per year.