Small Intestine and Colon

 

 
   

The small intestine is located between the gastric outlet and the colon. It is approximately 2.5 to 4 metres long. Its main function lies in the absorption of fluid and nutrients. With the exception of duodenal ulcers, diseases of the small intestine are rare.

The colon follows the outline of a square from the end of the small intestine in the lower right of the abdomen and extends to the anus. The length of the colon varies between 1.2 and 1.8 metres. The main function of the colon lies in the thickening of stools.

 
   
 
   

Methods of Examination

The main methods of examination used in the investigation of diseases of the small intestine and colon are explained below. In addition to these methods, x-rays investigations may also be carried out.

Endoskopy
The illumination and inspection of body cavities and hollow organs with the aid of an endoscope1; endoscopy also allows a sample of tissue to be removed (biopsy ) for further examination, if necessary in combination with an ultrasound examination (Endosonography), and can be used to carry out minor surgical procedures (e.g. electro- or laser cauterisation, endoscopic removal of polyps).

Coloscopy (also Colonoscopy):
The endoscopic examination of the colon using a special flexible endoscope (coloscope) with the facility to carry out a biopsy (removal of tissue sample) and minor surgical procedures (mainly the endoscopic removal of polyps).
When should an endoscopy/ coloscopy be carried out?
- In the case of continuous diarrhoea where the cause is uncertain
- In cases where blood is passed repeatedly or in cases of anaemia where the cause is uncertain
- In the case of suspicion of an inflammation of the intestine
- In the case of intestinal polyps or malignant tumours (carcinoma of the colon )

Proctoscopy , Rectoscopy
Where the examination is limited to the rectum, it is carried out using a non-flexible instrument. This provides the doctor with a large opening, allowing minor surgical procedures to be carried out through the instrument.

Gastroscopy , Oesophagogastroduodenoscopy
Following anaesthetisation of the mucous membrane of the throat, a flexible endoscope is passed via the mouth, throat and gullet into the stomach and duodenum. Nervous patients can be given a strong sedative in order that they remain largely unaware of the procedure. The advantage of this form of examination is that changes which indicate disease can immediately be seen and biopsied in order to conduct a fine-tissue analysis of the mucous membrane. Minor surgical procedures, such as cauterisation (haemostasis) can also be carried out via the endoscope.

 
   
 
   

Major disorders of the Small Intestine and Colon

1. Tumours
Here we distinguish between benign and malignant tumours. The following are benign tumours:
- Polyps
- Adenomas
- Hamartomas
The following are malignant tumours:
- the colonic carcinoma
- the rectal carcinoma
2. Haemorrhoids (piles)
3. Irritable bowel syndrome
4. Chronic inflammatory bowel diseases


 

Disorder 1: Polyps / Adenomas and Carcinomas of the Colon

1. Definition:
A polyp is any protrusion into the intestinal cavity. An adenoma is a tissue growth in the mucous membrane of the colon. A carcinoma is a malignant tumour, which commonly develops from adenomas Over 50% of colonic polyps or colonic carcinomas are located in the end part of the colon. Around 20% of patients over 60 years of age have colonic polyps. Carcinomas also predominate in elderly persons.

2. Symptoms and Signs
- 60% of patients display no symptoms (commonly the condition is detected by chance).
- Diarrhoea and secretion of mucus
- Pain due to constipation
- Spontaneous passing of blood or blood in bowel movements

3. Complications and Risks:
- Mutation of adenomas (development of malignant tumours)
- Haemorrhage
- Perforation of the intestine
- Spreading and formation of secondary growths

4. Diagnosis / Preliminary investigation
- Precautionary investigations for possible cancers should begin from the age of 45.
- Examination of the rectum using a finger
- Intestinal endoscopy with, where required, the removal of a sample of tissue or the removal of any polyps or adenomas
- Examination of the colon using a contrast medium (if intestinal endoscopy is not possible)
- Ultrasound examination (a special device which is used to see into the intestine).
- Major preliminary examinations: coloscopy with tissue biopsy. On suspicion of a malignant tumour, the possibility of secondary tumours must be investigated using ultrasound or computerised tomography.

5. Therapy / Treatment
In the case of polyps and adenomas: complete removal using the Endoscope.
In cases where there are indicators of malignant tumours or these are suspected - but without a large number of secondary tumours - surgery is a must. Either part of the colon or the entire colon is removed.
Procedure:

1. Single operation
2. Double operation with the temporary attachment of an artificial rectum, the rectum being remodelled in a second operation.
3. In the case of tumours which are situated very close to the anus (rectal carcinoma), a permanent
3. Within the framework of interdisciplinary treatment, many patients with advanced carcinomas are treated with chemotherapy or radiation therapy before and after surgery.

6. After-care
- Regular check-ups using intestinal endoscopy
- In the case of carcinoma further checks such as determining master tumor in the blood, ultrasound examination of the abdomen or computerised tomography (x-ray technology) to exclude possible secondary tumours is required.

Disorder 2: Haemorrhoids

1. Definition (What are Haemorrhoids?)
Haemorrhoids are enlarged veins in the anal region.

2. Symptoms and Signs (What are the signs of haemorrhoids?)
Blood in bowel movements is commonly caused by haemorrhoids (among other causes), and other symptoms are itching and occasional pain.

3. Complications and Risks
Occasionally, serious bleeding can occur.

4. Diagnosis / Preliminary Investigation (How are haemorrhoids diagnosed?)
Normally haemorrhoids are easy to diagnose. The examination is carried out using proctoscopy, rectoscopy or coloscopy.

5. Therapy / Treatment (How are haemorrhoids treated?)
At the Inselspital, the diagnosis and treatment of haemorrhoids are carried out in the gastroenterologists' proctological consulting rooms. There haemorrhoids can be tied off and destroyed (sclerosed) during a rectoscopy. In addition, surgeons have developed new operating procedures for the treatment of very large haemorrhoids.

6. After care
After care is required in the event that the symptoms reoccur.

Disorder 3: Irritable Bowel Syndrome

1. Definition: (What is irritable bowel syndrome?)
Irritable bowel syndrome often causes serious abdominal pain, most probably as a result of uncoordinated peristaltic movements

2. Symptoms and Signs (What symptoms do patients with irritable bowel syndrome have?)
Patients with irritable bowel syndrome commonly experience abdominal pain, which is often relieved following a bowel movement.

3. Complications and Risks
None

4. Diagnosis (How is irritable bowel syndrome diagnosed?)
Before irritable bowel syndrome can be diagnosed, all other colonic disorders must be excluded. Normally, an endoscopy is required to do this.

5. Therapy / Treatment (How is irritable bowel syndrome treated?)
The symptoms experienced by most patients can be relieved by taking medication.

6. After care
Regular check-ups are advisable to optimise the treatment with medication.

Disorder 4: Chronic Inflammatory Bowel Diseases

1. Definition (What is chronic inflammatory bowel disease?)
Chronic inflammatory bowel diseases include Crohn's disease and ulcerative colitis . These involve inflammation confined exclusively to the colon (= ulcerative colitis) or a possible attack affecting intestinal segments of quite variable size in which the entire gastrointestinal tract can in principal be affected (Crohn's disease). The cause of these diseases has not yet been fully clarified, although hereditary and environmental factors and disorders of the immune system are important. At the Inselspital there are several working groups which are engaged in scientific research into the origins and treatment of chronic inflammatory bowel diseases. As a result, patients at the Inselspital can benefit from the latest information and treatments on offer in this field.

2. Symptoms and Signs
Patients suffer from a wide variety of symptoms, such as abdominal pain, blood in bowel movements, diarrhoea, weight loss and fever. Occasionally, pain in the joints can also occur.

3. Complications and Risks
Chronic inflammatory bowel disease can lead to infections, which makes treatment with antibiotics or surgery necessary. Often there is bleeding, without this necessarily being dangerous. Serious haemorrhages or perforations of the intestinal wall are rare. In the case of Crohn's disease, intestinal obstruction is an additional complication.

4. Diagnosis
Normally a coloscopy has to be carried out. In addition, in the case of Crohn's disease, the small intestine must be examined using a special x-ray procedure. At the Inselspital, a diagnosis can also be made on the basis of blood tests in the majority of cases.

5. Therapy/Treatment
Most forms of treatment involve the influencing of the immune system through the use of medication. The aim of the treatment of patients with a chronic inflammatory bowel disease is always to bring the patient out of a particular phase of the disease quickly using the medication. Normally, consistent medicinal treatment can keep all the symptoms of the disease well under control.

The Inselspital is the only hospital in Switzerland so far to conduct interdisciplinary consultations, involving gastroenterologists and surgeons, to ensure the best possible treatment for these diseases (Telephone 031/632 8560). In the case of ulcerative colitis, the removal of the colon leads to the disease being cured. The artificial rectum (ileostomy) which has to be attached following removal of the colon is no longer required if a pouch operation is performed. In this operation, the small intestine is formed into a reservoir and joined to the natural rectum. In the case of Crohn's disease, surgery is only carried out in the event of complications (abscess, cicatricial atrophy).

6. After-care
As both Crohn's disease and ulcerative colitis are chronic diseases, regular check-ups are absolutely essential, as the inflammation must be kept at the lowest possible level at all times.