Acute gastroenteritis kills millions of young children every year, mostly in developing societies. In developed countries, it is a common reason for visits to the general or emergency department and hospitalization. Causes: 70% of children's gastroenteritis is caused by viruses, the most common of which are rotaviruses, and less than 10% by Protozoa (giardia and amoeba histolytica) and 10-20% by bacteria (campylobacter, salmonella, shigella, vibrio cholera, etc.) Diagnosis can be done clinically. Information on recent contact with persons with gastroenteritis, nature and frequency of stools and vomiting, travel, and use of antibiotics and other medications that may cause diarrhea should be sought. Chronic constipation is common in children, and faecal overflow incontinence may present as fecal diarrhea. Diarrhea and vomiting are nonspecific symptoms in young children, and the diagnosis of gastroenteritis should be questioned in children with high fever, prolonged symptoms, or symptoms suggestive of a surgical cause (eg, severe abdominal pain, bilious vomiting, abdominal mass). Children born with diabetes and metabolic errors may present with vomiting. Children with underlying medical conditions may be at increased risk of complications and referral to pediatric services should be considered. It is not necessary or practical to obtain a stool sample from all children with gastroenteritis. Samples should be taken during an outbreak – especially in a nursery, school, hospital or residence – where public health is necessary to identify the pathogen and determine its source. Samples should be cultured for bacteria and tested for viral pathogens. Testing for rotavirus, norovirus, and sometimes other viruses is available at most children's hospitals using methods for rapid antigen detection (such as enzyme-linked immunosorbent assay). Rapid diagnosis allows the child to be isolated to prevent nosocomial infection, which is common and is often used as an indicator of the effectiveness of contact infection control precautions. Stool samples should also be taken from children with dysentery, a history of recent foreign travel, and from young or immunocompromised children with high fever. Other non-viral causes of acute gastroenteritis include: bacterial causes of acute gastroenteritis (for example, Salmonella, Shigella, Escherichia coli, Campylobacter jejuni, Clostridium difficile), parasitic causes of acute gastroenteritis (for example, Giardia intestinalis, Entamoeba histolytica, antibiotics) , Cryptosporidium – enteropathic acrodermatitis, (diarrhea in otitis media and urinary tract infection), hemolytic uremic syndrome, malabsorption syndromes (eg celiac disease, cystic fibrosis, disaccharidase deficiency) and inflammatory bowel disease (eg Crohn's disease, ulcerative colitis). Personal hygiene is very important to prevent the spread of pathogens. This includes frequent hand washing with soap, careful disposal of diapers, and proper preparation and storage of food and drinking water. Contaminated objects and surfaces must be properly disinfected. Breastfeeding in the first year of life with exclusive breastfeeding in the first 6 months is recommended. The goal of treatment is to maintain adequate hydration for a child with gastroenteritis. Dehydration, which may be associated with electrolyte disturbances and metabolic acidosis, is the most common and dangerous complication. Optimal management with oral or intravenous fluids minimizes the risk of dehydration and its adverse consequences. Routine use of antibiotics, antidiarrheal medications, and antiemetics is not recommended and may cause harm. Prevention is the key to controlling gastroenteritis, and rotavirus vaccines have been effective.