Acute gastroenteritis, also know as the stomach flu, is an inflammation of the intestines caused by microbes. The most common causes of gastroenteritis are viruses and bacteria. Symptoms include fever, chills, headache, vomiting and diarrhea, which can lead to dehydration and electrolyte abnormalities. The main electrolytes affected by gastroenteritis are sodium and potassium.
Causes of Gastroenteritis
Viruses that cause gastroenteritis include rotavirus, which is the leading cause of diarrhea among children in the world, norovirus, which usually affects people in confined spaces like cruise ships, and the influenza virus. Bacteria responsible for the symptoms of gastroenteritis include E. coli, Salmonella and Shigella, which can cause food poisoning. Occasionally, parasites can cause gastroenteritis, especially in people whose immune systems are not working appropriately.
Symptoms of Gastroenteritis
Vomiting and diarrhea are the most prominent signs of acute gastroenteritis. Diarrhea is usually watery and foul smelling, and it can be bloody, especially in bacterial gastroenteritis. Fever, abdominal cramps, and poor appetite are also prominent symptoms. Dehydration and decreased intake of fluids can then lead to electrolyte imbalances. Signs of dehydration include dry lips and mouth, dry skin, lethargy and irritability. Infants and children with dehydration show no tears when crying, and decreased urine output. If dehydration remains uncorrected, people can become listless, unconscious, and, in severe cases, fall in a state of coma.
Sodium Imbalance
Sodium is one of the most important electrolytes affected by dehydration. Gastroenteritis can cause hypernatremia, or high sodium levels in the blood stream, when the body loses more water than electrolytes, concentrating the amount of sodium. On the other hand, hyponatremia, or low sodium levels, results when the body loses more sodium than water, especially in cases of severe vomiting and diarrhea. Signs of hyponatremia include headache, confusion and lethargy. High sodium causes thirst, confusion and seizures.
Potassium Imbalance
Potassium is mostly found inside the body's cells, so small changes in the potassium level in the bloodstream can have a significant impact in a person with gastroenteritis. High potassium can cause dangerous arrhythmias, or abnormal heart rhythms. In particular, it can cause ventricular fibrillation, a condition in which the heart quivers instead of beats, thereby decreasing its ability to deliver blood to the brain and the body. Low potassium usually causes milder symptoms, like muscle cramps, fatigue and constipation.
