Definition

Gastroenteritis is the inflammation of the wall layers of the stomach and small intestines. Signs of vomiting and diarrhea identify this condition. It is more common in children due to their not-yet-fully-developed immune system. Usually, gastroenteritis is caused by a viral infection, making it easily transmissible.

It is estimated that the number of gastroenteritis cases in children under 5 years old will reach 1 billion per year, with approximately 3 million deaths annually. Due to the high transmission rate among children and adults, it is important to understand the causes, symptoms, and ways to manage and prevent it.

Causes

Infections, drug side effects, and heavy metal contamination can cause gastroenteritis. Antibiotics, antacids, and chemotherapy Drugs may lead to gastroenteritis as a side effect. Heavy metals such as lead, arsenic, or mercury can induce gastroenteritis when inhaled from the air or consumed through water.

Gastroenteritis caused by infection is divided into viral gastroenteritis and bacterial gastroenteritis. While parasites such as Entamoeba histolytica and Cryptosporidium can also cause gastroenteritis, the form caused by bacteria typically results in bloody stools and is called dysentery.

• Viral gastroenteritis

Gastroenteritis is caused by a virus commonly known as stomach flu. The two primary viruses responsible for this condition are norovirus and rotavirus. Although adenovirus and astrovirus can also cause gastroenteritis, they are less common. The disease spreads easily through contact with infected individuals or consuming contaminated food and drinks. Viruses are particularly prone to spreading in daycare centers, schools, dormitories, or cruise ships.

• Bacterial gastroenteritis

Bacteria that infect the intestines and stomach typically come from food contaminated by bacteria or toxic substances produced by bacteria, leading to the condition commonly known as food poisoning. Some bacteria that can cause this include Yersinia (from pigs), Staphylococcus (found in milk, meat, and eggs), Shigella (usually found in water, such as pools), Salmonella (present in meat, eggs, and milk products), Campylobacter (associated with birds and meat), and E. coli (linked to salads and beef).

This disease can be transmitted easily through direct contact with contaminated hands. If an infected person touches food, objects, or others, the touched items can become a source of infection. The spread of the disease is closely related to poor hygiene practices.

Risk factor

These are groups more at risk of being affected by viral gastroenteritis:

• Children under 5 years old
• Elderly individuals (Advanced age)
• Adults or children with a weak immune system

They are at risk because their immune systems are not optimal for fighting the viral infections that cause gastroenteritis. The immune system is not fully developed in children or toddlers, while in elderly individuals, their immune systems are weakened.

In addition to age-related factors, some daily habits can increase the risk of gastroenteritis, such as:

• Hands are not being washed properly, especially for people who work in the kitchen.
• Consuming contaminated water or water polluted by viruses or bacteria.
• Consuming seafood from polluted water, especially if eaten raw or not fully cooked.

Symptoms 

Vomiting and diarrhea are the main manifested symptoms of gastroenteritis. These symptoms usually last 1-2 days but persist for up to 10 days. Some additional symptoms may include:

• Headache, muscle, or joint pain
• Fever or shivering
• Abdominal pain or cramps
• Low appetite

In cases of bacterial gastroenteritis, bloody stool may be present.

In cases of prolonged gastroenteritis, it is important to be aware of dehydration symptoms. The early signs of dehydration often include:

• Thirst and dizziness
• Dry mouth
• Reduced urine output
• Increased fatigue
• Dark and smelly urine

In cases of prolonged gastroenteritis, it is crucial to be vigilant for dehydration symptoms, especially in babies. The early signs of dehydration in infants include a sunken fontanelle, reduced or no tears while crying, a dry diaper after a few hours, increased fussiness in the early stages of dehydration, and reduced activity, accompanied by increased sleepiness in severe cases of dehydration. 

Diagnosis

The diagnosis of gastroenteritis is typically made through a combination of history-taking and a physical examination conducted by a physician. Key indicators such as vomiting and diarrhea are crucial in identifying and diagnosing gastroenteritis. Additionally, the stool characteristics, the presence of fever, the intensity of abdominal pain, and other relevant factors must be explored during the assessment to guide the physician in understanding or suspecting the underlying cause of gastroenteritis. This, in turn, informs the treatment plan.

For a more precise determination of the cause, the doctor may recommend additional examinations, such as a fecal examination. In this procedure, a feces sample is collected using a specific container and analyzed in the laboratory. The results of this examination can reveal the presence of bacteria, fungi, parasites, viruses, mucus, blood, pus, or undigested meat fibers, providing valuable insights into the specific cause of gastroenteritis.

Management

Gastroenteritis is usually self-healing since most cases are caused by viral infections. The management of gastroenteritis aims to prevent symptoms from worsening and to avoid dehydration.

Preventing dehydration and ensuring adequate nutrition are primary steps in managing gastroenteritis, particularly in children. Some steps that can be taken independently include:

• Fulfilling the daily water intake to prevent dehydration.
• Opting for frequent, small feedings.
• Consuming drinks and potassium-rich foods, such as fruit juice or bananas.
• Incorporating ginger into the diet may help fight infection and reduce abdominal pain.
• Avoiding milk products, fruits, or high-fiber foods to prevent more severe diarrhea."

To replace lost body fluids, Oral Rehydration Solutions (ORS) can be consumed. These solutions contain electrolytes and minerals that are beneficial in preventing dehydration. ORS is available over the counter or can be made independently by preparing a salt and sugar solution. It is important to be aware of the guidelines on the packet or follow instructions on mixing the solution before consumption.

In addition to the previously mentioned management strategies, doctors may prescribe medications to alleviate symptoms caused by gastroenteritis. Some medications that may be recommended include:

• Antibiotics, such as amoxicillin, can be used if the cause is bacterial.
• Antifungal medications like nystatin if a fungal infection causes it.
• Antidiarrheal medications like loperamide or attapulgite.
• Antipyretic drugs like paracetamol or ibuprofen if the body temperature exceeds 37.5 degrees Celsius.

Managing gastroenteritis in babies or children requires special attention because they are more prone to dehydration. If a child experiences vomiting or diarrhea, allow their digestive system to rest for 15-20 minutes. Gradually introduce fluids, starting with water, then progressing to Oral Rehydration Solution (ORS) or breast milk. Here are other steps that can be taken for children:

• Offer easily digestible foods with a soft texture, such as bread, potatoes, or bananas.
• Avoid providing dairy products, including food and drinks, especially those with high sugar.
• Refrain from giving over-the-counter anti-diarrhea drugs unless recommended by a doctor.

Complications

Severe gastroenteritis can lead to losing fluids and nutrients, resulting in the most common complication—dehydration. Symptoms associated with dehydration include dizziness, weakness, excessive thirst, dry mouth, and concentrated urine. It is important to be aware of these symptoms and seek prompt medical attention if they arise.

Prevention

The primary prevention of gastroenteritis involves maintaining personal hygiene and ensuring cleanliness in the surroundings. Proper handwashing is crucial, using warm water and soap for 40-60 seconds. Hand sanitizer can be used for 20-30 seconds without soap. Hands should be washed before eating, engaging in outdoor activities, and using the toilet.

After handwashing, additional preventive steps include:

• Avoiding the consumption of raw or undercooked food.
• Ensuring the cleanliness of drinks or water used for brushing teeth.
• Cleaning objects suspected to be contaminated by viruses or bacteria.
• Routinely cleaning bathrooms and kitchens, including frequently touched objects.
• Avoiding the sharing of tableware and bathroom items with others.

For babies, rotavirus vaccination is recommended. Rotavirus is the most common cause of gastroenteritis in children. In Indonesia, there are two types of rotavirus vaccinations: one given three times at 6-14 weeks, 18-22 weeks, and 8 months, and another given twice at 10 and 14 weeks. If the baby is older than 6-8 months and has not been vaccinated, the vaccination is not necessary.

When to see a doctor?

Usually, the symptoms of gastroenteritis are mild, and a visit to the doctor is not necessary, as the condition often self-heals with independent management and over-the-counter drugs to reduce symptoms.

However, if there are signs and early symptoms of dehydration, it's advisable to seek an examination at the nearest health facility. Signs of dehydration should be especially monitored in babies and children.

In addition to dehydration concerns, it's essential to seek medical attention if diarrhea does not improve after 3 days or more, particularly if there are indications of bloody stool.