Approach To A Patient With Chronic Diarrhoea

A 24 year old married man presents to his general physician with a history of watery diarrhea which has sometimes blood mixed in with the stools. He has lost some weight and also complains of arthralgia.. How would you approach this case ?

Clinical Approach:
The patient in this case is most likely suffering from idiopathic inflammatory bowel disease, but it is important to exclude chronic infection and to consider other causes of chronic diarrhea. Always make sure that the patient is actually having diarrhea that is increased daily stool volume.

History of Presenting Problem:

1. Character of the stool  knowing the character of the stool is very important for the appropriate diagnosis. The questions to be asked in history include:

• Frequency of passing the motion.
• Whether there is any urgency
• Any pain on defecation

2. Rectal Bleeding: If there is any rectal bleeding or blood in stool following should be clarified:

• is the blood passed freely per rectum without any stool?
• Is it mixed with stool
• is it only present on the toilet paper when the anus is wiped.

3. Passage of any mucus or pus in stool should be asked.

4. Exclude steatorrhoea by asking:

• is the stool bulky and light colored
• does it float on the water in the toilet
• does it have an offensive odour.

5. Assess the severity of diarrhea by asking:

• Is the stool extremely watery or passed in large volumes
• does the patient feel faint or unwell when passing stool
• is there undigested food in the stool.

6. Review the systemic symptoms and ask for:

• Non- specific malaise with or without weight loss.
• Fever
• Night sweats

7. Ask about any pain or abdominal cramping. If present the quality, character and site of pain should be assessed.

8. Relevant past history will include:

• Age of the patient at the beginning of the symptoms.
• history of similar episodes in past.
• Any medical condition that needed long term treatment for example tuberculosis.

Examination:

1. General Physical : The first important thing to note is whether the patient looks well, unwell or extremely unwell. Check vital signs and note the presence of fever, tachycardia or hypotension.

Measure the patient's weight and calculate the body mass index.

Examine the hands, skin, eyes, mouth and joints for any signs for systemic or multisystem disease. 

2. Gastroenterological: In a patient with chronic diarrhea the external examination of the abdomen may be unremarkable. Sometimes there may be tender areas due to underlying inflamed bowel. With ulcerative colitis , a thickened, fibrosed segment of sigmoid colon may be felt. Crohn's disease and ileocecal tuberculosis may cause an ill defined tender mass in the right illiac fossa. Generalized abdominal tenderness, scant bowel sounds or visible distension are generally signs of severe disease in acutely ill patients.

3.  Rectal Examination: is mandatory in patients presenting with a history of chronic diarrhea. Examine the anal verge for signs of excoriation, which may be a result of excess secretions. Many patients with crohn's disease will have anorectal involvement, with ulceration, fissuring and scarring. Insertion of the examining finger may be painful so patient should be warned. Blood and/or pus may be detected on the glove on withdrawal.

Investigations:

1. Examination of the stool for bacterial pathogens and for ova, cysts and adult forms of various parasites. Sometimes it may be necessary to measure the stool volume over a 24 hr period or to estimate fecal fat excretion over a 72 hr period.

2. Rigid Sigmoidoscopy: Should be performed if feasible. In cases of ulcerative colitis there is always rectal involvement , while in crohn's disease the rectum may be spared. Bleeding, ulcerationand a mucopurulent exudate may be seen. A biopsy should be taken for histological examination. 

3. ESR And C reactive Protein: The ESR and serum C reactive protein should be measured in all patients in whom inflammatory bowel disease is suspected. 

4. Plain abdominal radiograph: In patients suspected with severe colitis should be admitted and an abdominal radiograph should be obtained. Visible dilatation of the large intestine may be due to perforation and is an emergency. Pancreatic calcifications may help establish a diagnosis of chronic pancreatitis.

5. Colonoscopy: allows direct visualization of the entire mucosa  and should be performed in all patients with suspected colitis or crohn's disease. 

6. Ig A antibodies: The presence of IgA antibodies to endomysial antigens is diagnostic for celiac disease. 

Management: 

1. Check the volume status of the patient and if dehydrated it is important to resuscitate with normal saline. Hypotension should be corrected immediately. 

2. Corticosteroids and 5 aminosalicylic acid are used to treat inflammatory bowel disease. 

3. Cyclosporin given orally or intravenously may induce remission in severe colitis.

4. Long term immunosuppression with azathioprine and other agents is often used to maintain remission in both crohn's disease and ulcerative colitis. 

5. Emergent surgery and colectomy is indicated for toxic megacolon.

6. Attention to proper nutrition is important. Sometimes in cases like severe colitis  patients may require total parentral nutrition.