What is an anal abscess?
An anal abscess is a collection of pus in the tissues around the anus. As the infection progresses, pain develops with swelling and redness and continues until pus escapes.
Antibiotics may be used to control the spread of the infection but alone will not cure an abscess. Drainage of the pus is necessary to resolve the infection.
Despite incision and drainage, occasionally some anal abscesses develop into anal fistulas.
What is an anal fistula?
An anal fistula is an abnormal connection (tunnel) between the internal lining of the anus and the skin outside the anus. Anal fistulas form when an anal abscess bursts or when drained, the wound does not completely heal. Discharge of pus may be constant or intermittent together with variable pain as the external opening on the skin may heal temporarily.
An anal fissure is a tear or split in the skin that lines the anus. Patients usually present with pain on defecation and bright fresh rectal bleeding usually on the toilet paper. The pain associated with a fissure may be so severe that patients avoid going to the bathroom leading to constipation and even more pain. Rectal examinations are often difficult due to severe pain.
Fissures typically occur following trauma to the lining of the anal canal, this is commonly due to passing hard dry stool such as with constipation. They may also be associated with inflammatory conditions such as Crohn's disease.
Anal pain is a fairly common problem and various anal conditions can cause anal pain:
Less frequent causes of anal pain may include:
Bowel cancer is a malignant growth that develops most commonly in the lining of the large bowel. Bowel cancers develop from tiny growths called 'polyps'. Whilst not all polyps become cancerous, over time some polyps can become cancerous. In more advanced cases, the cancer can spread beyond the bowel to other organs. Polyps should be removed to reduce the risk of developing bowel cancer.
The risk of developing bowel cancer increases with age but is greater if the patient is:
How common is bowel cancer?
In Australia, bowel cancer is the most common internal cancer for both males and females combined. The disease is increasing as the average age of the population rises. 1 in 12 people will develop bowel cancer.
About 14,000 Australians are diagnosed with bowel cancer each year (including 1,000 under the age of 50). An estimated 19,960 are expected to be diagnosed in 2020.
What is the cause of bowel cancer?
The underlying cause of bowel cancer is not known. Some factors are thought to increase your risk. These include:
Research in genetics and molecular biology are increasing our knowledge of these inherited factors.
Symptoms
Colorectal cancer may cause one or more of the symptoms below:
Most of these symptoms are more often caused by conditions other than colorectal cancer, such as haemorrhoids, irritable bowel syndrome, or inflammatory bowel disease. If you have any symptoms or concerns, you should consult your doctor.
The good news is that bowel cancer is one of the most curable types of cancer, if detected early.
Bowel cancer can be detected using a variety of methods:
Colonoscopy - Under anaesthesia, a flexible tube with a video camera and light is inserted via the anus into the colon to allow the doctor to carefully examine the lining of the bowel. If a polyp is found, it may be removed during the procedure and sent for histology.
Sigmoidoscopy - Similar to colonoscopy, however this only examines the lower part of the bowel. If a precancerous polyp is detected during the procedure a full bowel examination by colonoscopy is usually needed.
Faecal Occult Blood Test (FOBT) - A simple test that can be done at home and looks for hidden traces of blood in a bowel motion. If an FOBT finds blood, further investigation (usually a colonoscopy) is needed to establish the cause.
Other detection methods - Other diagnostic tests may include blood tests, CT scan, ultrasound, PET scan and rectal examination.
Colonoscopy is regarded as the most accurate screening method to diagnose bowel cancer.
Crohn's Disease is an inflammatory bowel disease (IBD). It is chronic full thickness inflammation of the small and/or large bowel. The cause is unknown.
Diverticular disease or diverticulosis is a common condition of the colon (large bowel) that affects people as they get older. The great majority of patients have no symptoms and never get any symptoms.
Diverticular disease is the formation of abnormal pockets (diverticulum) in the bowel wall, while diverticulitis is inflammation or infection of these pouches.
Faecal Incontinence is the inability to control the passage of faeces or flatus from the anus. This can be severe with major accidents or minor with streaking or smearing of the underwear.
It is estimated that in Australia up to 5% of the population suffer from faecal incontinence. It is more common in the elderly and people in nursing homes. Due to childbirth injuries, faecal incontinence is also more common in women.
Haemorrhoids are prolapsing mucosa of the distal rectum containing an abundance of blood vessels. As the haemorrhoid enlarges it "bulges" into the anal canal and eventually may protrude at the edge of the anus (prolapse). Haemorrhoids can cause bright bleeding, discomfort but rarely severe pain unless complicated.
Types of haemorrhoids:
Polyps are growths that occur on the inner lining of the colon or rectum. Removal is recommended as over time some polyps may develop into cancer.
Polyps can vary in shape and size. They may be single or multiple. A polyp can look like a pea or wart and sometimes a small mushroom on a stalk. Some are flat and spread over the surface of the bowel.
Rectal bleeding is often seen as bright red blood on the toilet paper, usually after a bowel movement or seen in the toilet bowl water. Rectal bleeding can also present as extremely dark stool.
Not all rectal bleeding is visible to the eye. In some cases, evidence of rectal bleeding can only be seen through a microscopic examination of a stool sample.
What causes rectal bleeding?
Rectal bleeding is common and most causes are treatable and not serious. In some cases however, rectal bleeding can be a symptom of a serious disease, such as colorectal cancer. Therefore, all rectal bleeding should be reported to your doctor for investigation.
Rectal bleeding can be caused by:
A prolapse occurs when all or part of the rectal wall becomes loose and protrudes outside the anus. The exact cause of rectal prolapse is unknown.
Rectal prolapse is associated with by weakened pelvic floor and sphincter muscles that support the rectum keeping it in place. Rectal prolapse is also associated with advanced age and long term constipation and straining during defecation.
Ulcerative Colitis is as inflammatory bowel disease (IBD). It is chronic inflammation located in the inner lining of the large bowel only. The cause is unknown.
Ulcerative colitis is best diagnosed by endoscopy (colonoscopy or flexible sigmoidoscopy).