acute gastroenteritis Acute gastroenteritis refers to the acute inflammation of the gastrointestinal mucosa caused by various factors, often triggered by the consumption of contaminated, raw, or irritating food. The causes include bacterial, viral, and parasitic infections. This condition often occurs in the summer and autumn seasons, commonly transmitted through the fecal-oral route, and is more prevalent in children, with generally more severe symptoms in affected children. Clinical manifestations mainly include nausea, vomiting, abdominal pain, and diarrhea. In severe cases, fever, dehydration, electrolyte imbalances, and acid-base disturbances may occur, posing a threat to life.

Acute gastroenteritis refers to acute inflammation of the gastrointestinal mucosa caused by various reasons, usually triggered by the consumption of unclean, raw, or irritant foods. The causes include bacterial, viral, and parasitic infections. This condition often occurs in the summer and autumn seasons, commonly spread through the fecal-oral route, and is more prevalent in children, with generally more severe symptoms in affected children. Clinical manifestations mainly include nausea, vomiting, abdominal pain, and diarrhea. Severe cases can lead to fever, dehydration, electrolyte imbalance, and even life-threatening conditions.

Factors in children

Age

The younger the child, the more likely they are to develop acute gastroenteritis. Infants under 6 months of age are more prone to severe and prolonged diarrhea.

Feeding methods

Infants primarily fed with breast milk have a lower risk of developing acute gastroenteritis. Early and severe diarrhea in infants may be related to premature weaning.

Underlying chronic diseases or immunodeficiency

Children with malnutrition or immunodeficiency are at a greater risk of severe diarrhea, which may even progress to chronic gastroenteritis.

Environmental/socioeconomic factors

Attendance at daycare centers and lower socioeconomic status are more likely to lead to moderate to severe and prolonged diarrhea.

Factors in adults

Consumption of unclean food, including eating food contaminated by flies, carriers of pathogens, or patients, drinking untreated water, consuming raw or spoiled food, and food stored in the refrigerator for extended periods or frozen food;

Recent travel to or contact with epidemic areas;

Low immunity or malnutrition;

Prolonged and extensive use of antibiotics.

Viral acute gastroenteritis

Rotavirus gastroenteritis has an abrupt onset, often accompanied by fever, nausea, vomiting, and abdominal discomfort, with diarrhea typically following vomiting. The stool is watery or yellow-green. Norovirus gastroenteritis symptoms mainly include nausea, vomiting, abdominal pain followed by diarrhea, with watery stools occurring as frequently as over 10 times a day, possibly accompanied by low-grade fever, headache, decreased appetite, and fatigue. In children, vomiting usually precedes diarrhea and can lead to localized outbreaks.

Bacterial acute gastroenteritis

Most food poisoning cases occur within a few hours after eating, with a sudden onset of vomiting and diarrhea. Abdominal pain is mostly centered around the upper and middle abdomen. The vomit often consists of the ingested contaminated food, and mild cases of diarrhea occur several times a day, while severe cases can result in dozens of daily episodes. Invasive bacterial infections can lead to mucus and bloody stools due to damage to the intestinal mucosa. Some bacteria release enterotoxins causing acute gastroenteritis without invading the intestinal mucosa, resulting in stools without mucus or blood. Food poisoning is associated with the consumption of contaminated food, with affected individuals in a group setting showing varying severity of symptoms related to the amount consumed.

Parasitic acute gastroenteritis

Amoebic acute gastroenteritis is characterized by foul-smelling stools resembling jam. Giardia-induced acute gastroenteritis presents with explosive watery stools, often foul-smelling, frequently accompanied by bloating, foul-smelling flatulence, nausea, and vomiting.

Non-infectious acute gastroenteritis

In cases of non-infectious acute gastroenteritis, such as seafood allergy, severe, sudden, periumbilical pain can occur within a few hours of eating, followed by 2-3 episodes of watery diarrhea, with the abdominal pain subsiding afterwards, sometimes accompanied by hives. Acute stress or drug-induced cases may present with not only abdominal pain and diarrhea but also hematemesis and melena.

Fluid replacement is the primary treatment during the acute phase, and the method, amount, and rate of fluid replacement should be determined based on the degree of dehydration. Oral rehydration salt (ORS) is suitable for mild to moderate dehydration. The new low-osmolarity ORS formula reduces the sodium and glucose content, providing effectiveness comparable to standard ORS with lower incidence of adverse reactions. The use of rice-based ORS in treating cholera patients has shown better efficacy. Severe cases require intravenous fluid replacement, with a switch to oral rehydration after improvement. Healthcare providers may also arrange for supplementation of potassium, calcium, and zinc. Zinc supplementation in pediatric patients can improve prognosis and reduce recurrence.

Berberine hydrochloride, commonly known as huanglian su, is an alkaloid extracted from Chinese herbs. It exhibits inhibitory effects on various bacteria, particularly Shigella, Salmonella typhi, and Corynebacterium diphtheriae, with the strongest inhibition observed against Shigella. It can be used to treat bacterial acute gastroenteritis, with a certain effect in alleviating symptoms and relieving the condition, and with minimal side effects, it has gained wide recognition. Other traditional Chinese medicine treatments to alleviate symptoms include Liuwei Xianglian capsules and others. Additional traditional Chinese medicine treatment methods include herbal medicine based on syndrome differentiation, tuina massage, and acupuncture.

General recommendations

During the acute phase of gastroenteritis, it is advisable to rest, drink plenty of water, avoid overexertion, and refrain from smoking and drinking.

Dietary advice

For patients with acute gastroenteritis, gradual restoration of gastrointestinal function through proper dietary adjustments is recommended:

Due to impaired gastrointestinal function and decreased absorption, the diet should be light and rich in fluids, avoiding greasy, irritating foods, seafood, and raw or cold foods;

Suspend consumption of milk and other dairy products, fruit juice, etc., to avoid causing hyperosmolar diarrhea;

For patients with severe symptoms in the acute phase, a liquid diet can be adopted, such as thick rice soup, noodle soup, chicken soup, thick soy milk, tofu brain, etc.;

A liquid diet has limitations in food selection, cooking methods, and nutritional value, and should only be used for short periods;

Increase the frequency of meals, aiming for 6 meals per day;

Patients with mild symptoms can adopt a low-residue semi-liquid diet, with soft and easily digestible foods such as white rice porridge, egg custard, chicken noodle soup, scrambled eggs with tomatoes, etc., excluding fibrous vegetables such as leeks, celery, and lotus root;

Avoid consuming fried and dry legume foods that can cause intestinal bloating;

Gradually resume a regular diet after the diarrhea stops.

Infants should resume feeding as soon as possible during illness. Infants who were originally breastfed can continue breastfeeding, as acute gastroenteritis often results in secondary disaccharidase deficiency (mainly lactase). Therefore, formula-fed infants can opt for low-lactose or lactose-free formulas to avoid exacerbating diarrhea.

For older children, there are no dietary restrictions, and they can consume grains, meat, yogurt, fruits, vegetables, etc. Children in the growth and development stage should supplement the nutritional losses caused by acute gastroenteritis after recovery by choosing nutrient-rich foods and adding an extra meal daily for 2 weeks.

Practice good personal hygiene, wash hands before meals and after using the toilet;

Strictly disinfect vomit and eating utensils when family members are ill;

For infants and young children, pay attention to the preservation of dairy products and regularly disinfect feeding utensils, tableware, potties, and toys.

Avoid consuming raw foods, untreated water, and foods that have been stored for too long or have expired;

Consume cooked foods while hot, thoroughly reheating leftover foods before consumption;

Store raw and cooked foods separately, as well as disinfected and undisinfect utensils to avoid cross-infection;

Summer and autumn are peak seasons for this condition, so it is advisable to avoid crowded places as much as possible.

Vaccination

Rotavirus vaccine: Currently, two rotavirus vaccines have been approved for use, and vaccination can be arranged by a doctor based on local conditions;

Measles vaccine: It can greatly reduce the occurrence and severity of childhood diarrhea and should be administered according to the immunization schedule.