Gastroenteritis

Introduction

Gastroenteritis is an inflammation of the lining of the stomach and intestines, causing symptoms such as diarrhea, nausea, vomiting, and abdominal cramps. It is an infectious disease caused by viruses, bacteria, or parasites, transmitted through the ingestion of contaminated food or water, or through contact with an infected person. Highly common, it affects millions of people each year. Mild in most cases, it can be more severe in infants, the elderly, and vulnerable patients due to the risk of dehydration.

If you have severe diarrhea and vomiting, contact your primary care physician first. If they are unavailable, Docadom offers an emergency consultation by a home doctor: call 021 845 45 45 or use our app available on the App Store and Google Play.

Who is at risk?

Gastroenteritis affects everyone, but certain populations are more vulnerable. Children (especially infants), the elderly, pregnant women, travelers, and immunocompromised patients are more likely to develop a severe form or complications. Outbreaks are common in communities (nurseries, schools, nursing homes, hospitals), especially during the winter season.

Symptoms of Gastroenteritis

Symptoms appear a few hours to a few days after exposure and usually last from 24 hours to 5 days.

Main Symptoms

• Diarrhea: increase in the frequency and fluid consistency of stools, sometimes with mucus or blood.

• Vomiting often preceded by nausea.

• Abdominal pain in the form of cramps or spasms, occasionally localized.

• Fever, moderate to high depending on the cause.

• Loss of appetite, fatigue, and headaches.

• Dehydration: intense thirst, dry mouth, infrequent and dark urine, dry skin, dizziness.

When to consult urgently?

An emergency consultation is necessary in the following situations:

• Diarrhea persisting beyond 48 hours in adults, 24 hours in children.

• Presence of blood or pus in the stools.

• Uncontrollable vomiting preventing any fluid intake.

• Signs of dehydration: intense thirst, dry tongue, skin tenting, drowsiness — especially in infants and the elderly.

• High fever, intense or localized abdominal pain.

• Vulnerable patient: infant, pregnant woman, elderly person, immunocompromised, diabetic, kidney failure patient.

• Recent return from travel in a tropical area.

What to do before calling Docadom? Maintain hydration in small, frequent amounts (preferably oral rehydration solutions), and contact your primary care physician first. If they are unreachable or if you need a home doctor outside of opening hours, call Docadom at 021 845 45 45 or make your request directly from our smartphone app (App Store and Google Play). In case of serious signs (severe dehydration, drowsiness, heavy blood in stools), dial 144 without delay.

Causes of Gastroenteritis

Viral Gastroenteritis

This is the most common cause (about 70% of cases). The main viruses are rotaviruses (especially in children), noroviruses (winter outbreaks), adenoviruses, and astroviruses. Transmission is fecal-oral, through direct contact or contaminated surfaces. Symptoms typically last 1 to 3 days.

Bacterial Gastroenteritis

Often contracted by ingesting contaminated food or water (food poisoning). The main germs are Salmonella, Campylobacter, Shigella, Escherichia coli, Yersinia, and Clostridioides difficile (associated with antibiotics). Diarrhea is often bloody, fever is high, and recovery takes longer.

Parasitic Gastroenteritis

Less common, mostly after returning from travel: Giardia, Cryptosporidium, Entamoeba histolytica. Characterized by prolonged diarrhea, bloating, and weight loss.

Contributing Factors

Poor hygiene, unsafe drinking water, undercooked or poorly stored food, travel to high-risk areas, community living, contact with an infected person.

Diagnosis of Gastroenteritis

The diagnosis is primarily clinical. Additional examinations are necessary only in specific situations.

Diagnostic Methods

• Medical history: duration, stool features, travel history, suspected food, contacts, recent antibiotic therapy.

• Physical examination: hydration status, fever, abdominal pain, palpation.

• Stool culture: in case of bloody, prolonged diarrhea, or outbreak context.

• Testing for toxin of Clostridioides difficile in patients taking antibiotics.

• Parasitological examination of stools upon returning from travel or in case of chronic diarrhea.

• Laboratory tests: electrolytes, kidney function, CBC, CRP in case of severe forms.

Alternative Diagnoses

• Acute appendicitis (right lower quadrant pain).

• Inflammatory bowel diseases (Crohn's disease, ulcerative colitis).

• Irritable bowel syndrome.

• Food intolerance (lactose, gluten).

• Drug-induced diarrhea.

• Fever upon returning from travel (malaria, typhoid).

Treatment of Gastroenteritis

Treatment is mainly based on rehydration and managing symptoms.

Rehydration

This is the cornerstone of treatment. Drink in small, frequent amounts, water or preferably an oral rehydration solution (ORS) available in pharmacies. For infants, ORS is essential. In case of severe dehydration or vomiting that prevents oral hydration, intravenous rehydration in a hospital environment is required.

Medications

• Antiemetics: metoclopramide, ondansetron to reduce vomiting.

• Antidiarrheals: loperamide (Imodium®) in case of non-bloody diarrhea without fever. To be avoided in children.

• Antispasmodics: phloroglucinol (Spasfon®).

• Antibiotics: reserved for severe and identified bacterial gastroenteritis (azithromycin, ciprofloxacin, metronidazole for C. difficile).

• Probiotics: Saccharomyces boulardii, Lactobacillus rhamnosus GG — can shorten the duration of diarrhea.

Diet

Gradual resumption, starting with bland foods: rice, pasta, banana, applesauce, toast. Temporarily avoid dairy products, fats, and fiber-rich foods.

Prevention of Gastroenteritis

• Handwashing with soap, thorough and frequent, especially before meals and after using the restroom.

• Food hygiene: wash fruits and vegetables, cook food thoroughly, respect the cold chain.

• Safe drinking water or bottled water in high-risk areas.

• Avoid close contact with a sick person; do not share utensils, towels, or toothbrushes.

• Clean and disinfect surfaces, toilets, and toys.

• Rotavirus vaccination recommended for infants.

• Specific vaccinations (typhoid, cholera) before traveling to a high-risk area.

• School or work exclusion during the acute and contagious phase.

Possible Complications

The main complication is severe dehydration, especially in infants and the elderly, which can lead to acute kidney failure, electrolyte imbalances, consciousness disorders, or even death. Other complications are possible: hemolytic uremic syndrome (in children after enterohemorrhagic E. coli infection), septicemia, reactive arthritis, digestive perforation (typhoid), and prolonged post-infectious diarrhea.

When to Contact a Doctor for Gastroenteritis

The majority of gastroenteritis cases resolve spontaneously within a few days. Here is what to do if it worsens or persists:

• First resort: contact your primary care physician, who can assess the severity and prescribe appropriate treatment.

• If your primary care physician is unavailable (evenings, weekends, holidays), Docadom offers an emergency consultation by a home doctor. Call 021 845 45 45 or make your request via our mobile app, available for free on the App Store and Google Play.

• In case of serious signs (severe dehydration, drowsiness, heavy blood in stools, intense abdominal pain), dial 144 immediately.

Conclusion: Hydrate, Monitor, Consult if in Doubt

Gastroenteritis is a common condition, mostly benign, but it can be serious in vulnerable individuals due to the risk of dehydration. It is characterized by diarrhea, vomiting, abdominal pain, and sometimes fever, which can lead to complications such as severe dehydration, acute kidney failure, or hemolytic uremic syndrome in children. Hydration and compliance with hygiene rules are the keys to management and prevention.

If in doubt, contact your primary care physician first. If they are not available, Docadom provides an emergency home doctor 7 days a week: call 021 845 45 45 or use our mobile app (App Store, Google Play) to request an emergency consultation.