Investigating diarrhoea: when to see a doctor?

Diarrhoea is an extremely common and unpleasant symptom that almost everyone experiences in their lifetime. Although it is mostly harmless and goes away on its own in a few days, in some cases it can be a sign of a more serious illness. In this article, we explain in detail the medical background, types and possible causes of diarrhoea, and help you decide when home treatment is sufficient and when you need to consult a gastroenterologist.

What constitutes diarrhoea from a medical point of view?

Diarrhoea is medically defined as the passing of loose or watery stools more than three times a day. The Bristol stool scale is often used to assess stool consistency, with types 6 and 7 (pasty and completely liquid stools respectively) corresponding to a diarrhoeal state.

It is important to distinguish between acute and chronic diarrhoea:

• Acute (acute) diarrhoea: It starts suddenly and usually lasts for a short time, up to 14 days.
• Persistent (persistent) diarrhoea: lasts between 14 and 30 days.
• Chronic (chronic) diarrhoea: It takes longer than 30 days and requires a thorough medical examination.

Possible causes of diarrhoea

Diarrhoea can be caused by a number of factors, from simple infections to more serious digestive diseases. Understanding the underlying causes is key to proper treatment.

Common causes (especially in acute diarrhoea)

• Infections: The most common cause of acute diarrhoea. Pathogens may include:

- Viruses: Norovirus, rotavirus, adenovirus. These cause the majority of cases of what are colloquially known as „indigestion” or „intestinal infection”.

- Bacteria: Salmonella, Campylobacter, Shigella, E. coli. They are often introduced through food poisoning.

- Parasites: Giardia lamblia, Entamoeba histolytica. Can be spread by contaminated water or food.

• Drug side effects: Many medicines can cause diarrhoea, such as antibiotics (which upset the balance of the gut flora), antacids, or certain chemotherapy drugs.
• Food intolerances and allergies: If you are sensitive to lactose (milk sugar), fructose (fruit sugar) or gluten (coeliac condition), your body cannot digest these substances properly, which causes diarrhoea.
• Dietary factors: Foods containing high levels of sugar alcohols (e.g. sorbitol, xylitol), excessive fibre or fat intake, spicy foods can also cause temporary diarrhoea.

Possible causes of chronic diarrhoea

If the diarrhoea lasts for more than a month, a more serious investigation is needed. Possible underlying diseases:

• Irritable bowel syndrome (IBS): A functional disturbance of the gut-brain axis, associated with abdominal pain and changes in bowel movements. Diarrhoea-dominant IBS (IBS-D) is one of the most common subtypes.
• Inflammatory bowel diseases (IBD): Crohn's disease and ulcerative colitis are autoimmune diseases associated with chronic inflammation of the digestive tract, with the leading symptom being bloody, mucopurulent diarrhoea.
• Microscopic colitis: An inflammatory condition of the large intestine that can only be detected by histological examination (colonoscopy). It is characterised by watery, non-bloody, chronic diarrhoea.
• Absorption disorders (malabsorption):

- Coeliac disease (celiac disease): An autoimmune reaction triggered by gluten, which leads to damage to the lining of the small intestine and insufficient absorption of nutrients. Characterised by bulky, fatty, foul-smelling stools (steatorrhoea).

- Contaminated small bowel syndrome (SIBO): Abnormally proliferating bacteria in the small intestine ferment carbohydrates, causing bloating, gas and diarrhoea.

- Pancreatic insufficiency: The pancreas does not produce enough digestive enzymes, resulting in fat malabsorption and fatty diarrhoea.

• Endocrine (hormonal) causes: Hyperthyroidism, diabetes mellitus or rare neuroendocrine tumours can also cause chronic diarrhoea.
• Conditions after surgery: Gastric or intestinal surgery (e.g. removal of the gall bladder, resection of part of the small intestine) can alter the digestive process, which can lead to diarrhoea.

When should we see a doctor? The warning symptoms

Although most cases of acute diarrhoea can be treated at home, in some cases a specialist gastroenterological examination is essential. Consult a doctor if you experience any of the following „warning” symptoms:

• (Chronic) diarrhoea lasting more than 30 days.
• High fever of over 38.5°C.
• Bloody or pitchy (black) stools.
• Severe, cramping abdominal pain.
• Signs of dehydration: Decreased urine volume, dark urine, dry mouth, dizziness, weakness.
• Unintentional weight loss.
• Diarrhoea at night that wakes you from sleep.
• Old age (over 70) or weakened immune system.
• A family history of inflammatory bowel disease or cancer.

If you notice any of the above symptoms, don't delay getting checked out! Visit Endomedix Gastroenterology Centre experienced specialists to help you make an accurate diagnosis and start the right therapy.

How diarrhoea is investigated

The gastroenterologist decides on the necessary diagnostic steps after a thorough history and physical examination. Don't be alarmed by the tests, they are painless or mildly uncomfortable and are essential to get to the root of the problem.

• Laboratory tests:

- Blood collection: A complete blood count may indicate inflammation or anaemia. Monitoring liver and kidney function, ions, thyroid hormones and inflammatory markers (e.g. CRP) also provide important information.

- Stool analysis: Analysis of the stool sample is key. It can also be tested for occult bleeding (faecal blood test), pathogens (faecal culture), parasites, inflammation (faecal calprotectin) and digestion (fat content).

- Coeliac serology: Blood tests can detect antibodies that are characteristic of celiac disease.

• Exhalation tests: Painless tests that measure the composition of exhaled air after ingesting a special test solution.

- Lactose and fructose intolerance test.

- Lactulose/glucose breath test: It is used to detect small intestinal bacterial overgrowth (SIBO).

• Endoscopic examinations: These tests allow a direct view of the inner surface of the digestive tract. The procedures can now be performed under general anaesthesia, minimising discomfort. From Endomedix Gastroenterology Centre with modern equipment and empathetic staff to ensure that tests are carried out with care.

- Gastroscopy (gastroscopy): An examination of the oesophagus, stomach and horseshoe casing, which may include a biopsy, for example in suspected cases of coeliac disease.

- Colonoscopy (colonoscopy): An overview of the entire large intestine and the last part of the small intestine. Essential for the diagnosis of inflammatory bowel diseases, microscopic colitis and tumours.

• Imaging studies: An abdominal ultrasound, CT or MR scan can help to detect structural abnormalities in the digestive organs.

Tips for treating diarrhoea at home

In mild, acute diarrhoea, if there are no alarming symptoms, you can do the following to relieve symptoms:

• Fluid replacement: The most important thing is to prevent dehydration! Drink plenty of fluids: water, filtered tea, diluted juices. Oral rehydration solutions (ORS) available from pharmacies can also help replenish salts and minerals.
• Diet: During the first few days of diarrhoea, a sparing diet is recommended. Avoid fatty, spicy, dairy and high-fibre foods. Suggested foods: boiled potatoes, rice, toast, roti, bananas, steamed carrots. As symptoms subside, gradually return to a normal diet.
• Over-the-counter products:

- Coal tablets and tummy-traps (e.g. loperamide): They bind toxins and slow down bowel movements. It is important to note that they are not always recommended for bacterial infections, as they may inhibit the elimination of pathogens from the body. In case of high fever or bloody stools, always consult a doctor before using them.

- Probiotics: Preparations containing beneficial gut bacteria can help restore the balance of the gut flora, especially after a course of antibiotics.

The road to recovery

Although diarrhoea is unpleasant, it is in most cases a manageable symptom. The key is to listen to your body's signals. While a short period of mild diarrhoea is usually nothing to worry about, there may be a more serious problem behind persistent or alarming symptoms.

Don't live with unpleasant symptoms and don't be afraid to see a doctor! Modern diagnostic procedures are now gentle and effective. Visit Endomedix Gastroenterology Centre our team of experts is committed to identifying the cause of your symptoms and providing you with a personalised treatment plan to help you recover as quickly as possible. Take the first step towards your health!