ANSWER 32
The pattern of the pain, the absence of physical signs, normal investigations and repro-
duction of the pain during sigmoidoscopy all make it likely that this isirritable bowel
syndrome(IBS). This is a very common condition accounting for a large number of refer-
rals to gastroenterology clinics. IBS is often episodic, with variable periods of relapse and
remission. Periods of frequent defaecation alternate with periods of relative constipation.
Relapses are often associated with periods of stress. In IBS it is common to have a history
of other conditions such as migraine and menstrual irregularity. Under the age of 40 years
with a history of 6 years of similar problems, it would be reasonable to accept the diag-
nosis and reassure the patient. However, the family history of carcinoma of the colon
raises the possibility of a condition such as familial polyposis coli. The family history, the
circumstances of the grandmother’s death and the patient’s feelings about this should be
explored further. Anxiety about the family history might contribute to the patient’s own
symptoms or her presentation at this time. If there are living family members with poly-
posis coli, DNA probing may be used to identify family members at high risk. If any doubt
remains in this woman it would be sensible to proceed to a barium enema or a colonoscopy
to rule out any significant problems.
The diagnosis of IBS relies on the exclusion of other significant conditions such as inflam-
matory bowel disease, diverticular disease or large-bowel malignancy. In patients under
the age of 40 years it is usually reasonable to do this on the basis of the history, exam-
ination and a normal full blood count and ESR. In older patients, sigmoidoscopy and bar-
ium enema or colonoscopy should be performed. A plan of investigation and management
should be clearly established. The symptoms tend to be persistent and are not helped by
repeated normal investigations looking for an underlying cause. Symptoms may be helped
by antispasmodic drugs or tricyclic antidepressants. Some patients will benefit from the
consumption of a high-fibre diet.
- Irritable bowel syndrome is a common disorder and difficult to treat.
- Explanation of the condition to the patient is an important part of the management.
- Sigmoidoscopy with air insufflation often reproduces the symptoms of IBS.