Altered bowel habit

The normal bowel habit varies between several evacuations per day to one every 3 days or so. Changes in bowel habit may be the first symptom of serious underlying disease. Constipation may be used by the patient to describe hard pellety stools, infrequent defecation or excessive straining at stool with difficulty in evacuation (dyschezia). Similarly, diarrhoea may be used to describe frequent defecation, loose or fluid stools, urgency of defecation, Ihe persistent desire to defecate or faecal incontinence. Tenesmus, the feeling of incomplete rectal evacuation with a persistent desire to defecate, is common in infective colitis, rectal carcinoma, rectal prolapse and the irritable bowel syndrome.

The irritable bowel syndrome is a common cause of altered bowel function in patients under the age of 50 years. The principal symptoms include episodic constipation and diarrhoea associated with abdominal distension, intermittent abdominal pain relieved by defecation and often accompanied by non-specific symptoms including dyspepsia, urinary frequency, backache and tiredness (Table 5.11).

The important questions in the clinical history of patients with diarrhoea and the common causes are shown in Tables 5.12 and 5.13.

TABLE 5.11 Criteria for the diagnosis of irritable bowel syndrome

Continuous or recurrent abdominal pain or discomfort, relieved by defecation or associated with altered stool frequency or consistency, together with either or both of the following features:

Altered pattern of defecation for at least 25% of the time. i.e. two or more of the following: altered stool frequency (> 3/day or < 3/week) altered stool form (lumpy, hard, loose, watery] altered stool passage (straining, faecal urgency, feeling ol incomplete emptying) passage of mucus

Abdominal distension or a feeling of abdominal bloating

TABLE 5.12 Symptom checklist in patients with diarrhoeal disorders

Is the diarrhoea acute, chronic or intermittent? Is there tenesmus, urgency or incontinence? Is the stool watery, unformed or semisolid? Is the stool of large volume and not excessively frequent suggesting small bowel disease?

Is the stool of small volume and excessively frequent suggesting large bowel disease? Is there blood, mucus or pus associated with the stool? Does diarrhoea occur during the night, suggesting organic disease? Is there a history of contact with diarrhoea or of travel abroad? Does the sexual history provide a clue (gay bowel syndrome. HIV)? Is there a history of alcohol abuse or relevant drug therapy? Is there a past medical history of Gi surgery, Gl disease or Inflammatory bowel disease?

Is there a family history of Gl disorder, e.g. gluten enteropathy, Crohn's? Are there any other Gl symptoms, e.g. adomlnal pain and vomiting? Are there symptoms of systemic disease, e.g. rigors or arthralgia?

TABLE 5.13 Important causes of diarrhoea

Acute

Infective gastroenteritis

Drug therapy, e.g. antibiotics, melenamic acid

Citronic

Irritable bowel syndrome

Inflammatory bowel disease

Parasitic gut infections

Drug therapy, e.g. laxatives

Malabsorption

Bowel resection

Autonomic neuropathy

Faecal impaction

Colorectal malignancy

Metabolic disorders, e.g. thyrotoxicosis

The nature of any medication, prescribed or self-administered, should be established. Patients may be unaware of the laxative effects of some agents, e.g. magnesium-containing antacids, mefenamic acid: or the constipating effects of others, e.g. aluminium-containing antacids, codeine phosphate or iricyclic antidepressants.

Questions to ask patients complaining of constipation, and some of its possible causes, are shown in Tables 5.14 and 5.15. Constipation and faecal incontinence or soiling may coexist, especially with faecal impaction in children or the elderly. It is important to determine the timing and frequency of defecation, any association with abdominal, rectal or anal pain and any difficulty, urgency or tenesmus experienced during evacuation. In addition, the patient should be asked to describe the appearance, colour, consistency and characteristics of the faeces. Sometimes words like "stools' or 'faeces' are not understood and if there is doubt it is best to use colloquial phrases.

Special enquiry should he made about the presence of blood and pus or mucus, often described by the patient as

TABLE 5.14 Symptom checklist in patients with constipation

Has constipation been lifelong or is it ol recent onset? How often do the bowels empty each week? How much time is spent straining at stool? Is there associated abdominal pain, anal pain on defecation or rectal bleeding?

Has the shape of the stool changed, e.g. become pellet-like? Has there been any change in drug therapy?

TABLE 5.15 Important causes of constipation

Dietary fibre deficiency

Irritable bowel syndrome

Drug Iherapy, e.g. opiates

Intestinal obstruction

Immobility and lack of exercise

Metabolic disorders, e.g. hypothyroidism, hypercalcaemia

TABLE 5.16

Characteristic abnormalities of slooi colour

Tarry black

Upper gastrointestinal haemorrhage (melaena)

(proximal to the transverse colon),

e.g. peptic ulcers, caecal angiodysplasla

Iron or colloidal bismuth therapy

Bloody

Ulcerative colitis

Colorectal tumours

Colonic diverticulitis

Pale

Fat malabsorption (steatorrhoea) from either

small bowel or pancreatic disease

Silvery

Combination of steatorrhoea and

gastrointestinal haemorrhage,

e.g. pancreatic carcinoma

TABLE 5.17 Causes of bright red rectal bleeding

Haemorrhoids Anal fissure Colorectal polyps Colorectal malignancy Inflammatory bowel disease Complicated diverticular disease Ischaemic colitis case history

A 45-year-old woman presented with breathlessness on exertion, tiredness and aches and pains in the back and limbs. Systemic enquiry revealed painless abdominal bloating, occasional loose stools, weight loss of 6 kg over 12 months and more recently, intermittent dysphagia. Ever since the menarche. she has had recurrent crops of mouth ulcers occurring especially at menstruation, As a teenager and subsequently during two pregnancies, she had been found to have an iron-deticiency anaemia for which no cause had been found.

Clinical examination findings were unremarkable except tor pallor of the mucous membranes and tests for occult blood In the stools were negative. Investigations confirmed recurrence of her Iron-deficiency anaemia together with a decrease in the serum concentrations of calcium and phosphate to suggest vitamin D deficiency. Upper Gl endoscopy of the oesophagus, stomach and duodenum was unremarkable.

The diagnosis of gluten enteropathy (coeliac disease! was confirmed by the presence of high titres in the serum of endomysial antibodies and total villous atrophy on duodenal biopsy. 3 months alter strict adherence to a gluten-free diet, all of her symptoms had resolved completely. Dysphagia was attributed to the mucosal changes associated with severe iron deficiency (sideropenic dysphagia) and the musculoskeletal symptoms attributed to osteomalacia.

Learning points

• Gl disorders may present with non-specific and/or non-alimentary symptoms.

• Recurrent mouth ulcers are a typical feature of gluten enteropathy and inflammatory bowel disease.

• The symptom of dysphagia requires direct visualisation of the oesophagus lo exclude sinister causes,

• In the absence of Gl bleeding, recurrent iron deficiency suggests a malabsorption syndrome.

"slime'. Since many patients do not normally inspect their faeccs, only positive observations should be accepted; if necessary, the clinician should confirm the description by inspection of the stools. Abnormalities such as threadworms, roundworms or segments of tapeworms may also be present. Examples of abnormal stool colour arc given in Table 5.16,

Living Gluten Free

Living Gluten Free

A beginners guide that will reveal how living "G" free can help you lose weight today! This is not a fad diet, or short term weight loss program that sometimes makes you worse off than before you started. This is a necessity for some people and is prescribed to 1 out of every 100 people on earth by doctors and health professionals.

Get My Free Ebook


Post a comment