What is diarrhoea?

Definition and general information

Diarrhea is a condition characterized by frequent and loose stools. It is one of the most common manifestations of gastrointestinal disorders that can cause discomfort and complications if not treated properly. Diarrhea can be acute if it appears suddenly and lasts no more than two weeks, or chronic if it continues for several weeks or months. Acute diarrhea is often associated with infections or food poisoning, while chronic diarrhea often indicates a long-term health problem, such as inflammatory bowel disease or malabsorption syndromes.

Epidemiology

Diarrhea is a global public health problem, especially in developing countries with limited access to clean water and sanitation. It is one of the main causes of child mortality. According to the World Health Organization, diarrhea causes about 525,000 child deaths worldwide each year. In developed countries, diarrhea is often associated with food poisoning and viral infections. Travelers are often at risk of contracting diarrhea when visiting regions with low levels of hygiene. This condition is often called "traveler's diarrhea" and usually results from consumption of local water and food.

Seasonal variations affect the incidence of diarrhea, as different pathogens are more active at certain times of the year. For example, rotavirus infections are more common in the winter months, while bacterial infections such as Salmonella are more common in the summer, when high temperatures encourage bacteria to multiply in food.

Causes of diarrhea

Infectious factors

Infectious agents are the most common causes of diarrhea, including bacteria, viruses, and parasites that enter the body through contaminated food or water. Bacterial pathogens such as Salmonella, Escherichia coli, and Campylobacter are common causes of diarrhea. These microorganisms produce toxins that irritate the intestinal mucosa, causing inflammation and accelerated intestinal peristalsis. In some cases, the bacteria can also cause blood infections or other serious systemic inflammation.

Viral infections such as rotavirus and norovirus are common causes of diarrhea in children. Rotavirus is especially dangerous for babies and young children because it can cause rapid dehydration. Norovirus, which often causes outbreaks of diarrhea in communities and confined spaces, can spread very quickly, infecting large numbers of people. These viruses are highly contagious and are often spread through contaminated items or direct contact with an infected person.

Parasitic infections such as Giardia lamblia and Entamoeba histolytica are less common but can cause prolonged and severe diarrhea. These infections often occur in places with poor sanitation and hygiene. Parasites can enter the body through contaminated water or food and cause intestinal inflammation and dysfunction, which can lead to chronic diarrhea.

Non-infectious factors

Inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis, are chronic conditions that cause repeated episodes of diarrhea. These diseases are characterized by intestinal inflammation and damage that disrupts the normal digestive process. Crohn's disease can affect any part of the intestinal tract, while ulcerative colitis usually affects only the large intestine. Celiac disease and irritable bowel syndrome are other causes of chronic diarrhea related to specific dietary factors and bowel disorders. Celiac disease causes atrophy of the intestinal villi, which interferes with the absorption of nutrients, while irritable bowel syndrome is associated with functional disturbances in the functioning of the intestine.

Other noninfectious causes may be related to stress, anxiety, or other psychological factors affecting bowel function, leading to episodes of functional diarrhea. Psychosomatic stress can increase intestinal motility and cause intestinal irritation, which contributes to diarrhea.

Symptoms of diarrhoea

Acute diarrhea

Acute diarrhea usually starts suddenly and lasts no more than two weeks. The main symptoms are frequent and loose stools, which may be accompanied by abdominal cramps, bloating and nausea. In some cases, fever and general weakness may appear. Symptoms of acute diarrhea can be very intense and cause significant discomfort.

In acute diarrhea, it is important to quickly recognize signs of dehydration, such as dry mouth, infrequent urination, and fatigue, as fluid loss can be significant. Special attention should be paid to children and elderly people who are more sensitive to dehydration. If dehydration is not treated in time, it can lead to serious complications such as shock or kidney failure.

Chronic diarrhoea

Chronic diarrhea is a condition that lasts for more than four weeks and is often associated with underlying medical conditions. Symptoms can be similar to acute diarrhea, however, chronic diarrhea is often associated with weight loss, nutrient deficiencies, and general exhaustion. Lack of nutrients can weaken the immune system and increase the incidence of other diseases.

Patients with chronic diarrhea often complain of constant fatigue, abdominal pain and bowel disorders. In some cases, there may also be skin changes, mouth ulcers, or joint pain that indicate systemic disease. Since chronic diarrhea can be associated with serious health problems, such as inflammatory bowel disease or malabsorption syndromes, it is important to perform a detailed examination and establish an accurate diagnosis.

Diagnostics

History and physical examination

Physical examination includes palpation of the abdomen to assess the location and intensity of pain. The doctor may also check for signs of dehydration, such as skin turgor and mucous membrane moisture. A physical examination helps determine whether additional tests, such as laboratory tests or imaging, are needed.

Laboratory tests and other investigative methods

Laboratory tests are important to confirm the diagnosis and rule out other possible causes. Blood tests are often done to assess inflammatory markers, electrolyte levels, and kidney function. Blood tests can also detect anemia or other nutrient deficiencies associated with chronic diarrhea.

Analysis of stool samples may reveal infectious pathogens, parasites, or blood, indicating possible intestinal damage. This analysis is particularly useful for detecting bacterial or parasitic infections. In some cases, an intestinal biopsy may also be needed to look for signs of inflammation or celiac disease.

Endoscopic examination methods, such as colonoscopy or sigmoidoscopy, allow direct assessment of the condition of the intestinal mucosa and identification of signs of inflammation, infection or tumors. These methods are essential to confirm the diagnosis and choose an optimal treatment plan. Imaging techniques such as abdominal ultrasonography or computed tomography can help rule out structural abnormalities or tumors, as well as assess the thickness of the intestinal wall and the condition of other organs.

Treatment options

Prevention

Health hygiene and nutritional advice

Prevention is essential to reduce the risk of diarrhea. Maintaining good hygiene, such as regular hand washing with soap and water, is an effective way to prevent the spread of infections. Safe food preparation and storage is important to prevent food poisoning. When traveling to regions with poor sanitation, it is recommended to drink only bottled or boiled water and avoid raw foods.

Vaccination, such as against rotavirus, is an essential preventative measure for infants to reduce the risk and severity of diarrhoea. Vaccination helps reduce the spread of infections and protects against severe forms of the disease.

Dietary recommendations include a balanced diet with sufficient fiber and fluid intake to ensure normal bowel function. A balanced diet promotes gut health and prevents constipation or diarrhea. In case of lactose intolerance or other food intolerance, the relevant products should be avoided, replacing them with suitable alternatives.

Complications and consequences

Short-term complications

Short-term complications are mainly related to dehydration, which can lead to electrolyte imbalance and kidney failure. Severe dehydration can be life-threatening, especially in infants and the elderly, if not treated in time. Dehydration can also cause dizziness, loss of consciousness, and increased heart rate.

Long-term complications

Long-term complications can include nutritional deficiencies and weight loss, leading to weakness and a weakened immune system. Chronic diarrhea can lead to secondary health problems such as anemia and osteoporosis related to malabsorption. Anemia results from a lack of iron and vitamins, while osteoporosis develops from a deficiency of calcium and vitamin D.

Conclusions