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Vomiting and diarrhea due to acute infectious gastroenteritis remains one of the most common etiologies of childhood morbidity and mortality, especially in impoverished countries.
Bilious vomiting in a neonate raises suspicion for bowel obstruction, especially malrotation, with or without a volvulus.
Life-threatening causes of vomiting include bowel obstructions, increased intracranial pressure, diabetic ketoacidosis, and inborn errors of metabolism.
Life-threatening causes of diarrhea include toxic megacolon and Escherichia coli 0157.
Most dehydrated patients with gastroenteritis can be treated with oral rehydration solutions that now contain lower concentrations of glucose and sodium.
Most cases of acute gastroenteritis are viral in nature and resolve with minimal intervention and without antibiotic therapy.
Ondansetron can facilitate oral rehydration therapy (ORT) and decrease the need for IV therapy.
Rotavirus is the most common cause of infectious diarrhea worldwide and the leading cause of infant death in the developing world.
New vaccines against rotavirus are safe and effective and have decreased morbidity and mortality associated with rotavirus gastroenteritis.
Campylobacter are the most common cause of bacterial gastroenteritis in developed countries and have been implicated as one of the cause of traveler's diarrhea.
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Vomiting is defined as the forceful expulsion of the contents of the stomach. Most acute infectious illnesses result in frequent vomiting of a short duration. In children, the most common cause of vomiting is acute gastroenteritis. The vomiting history should focus on the duration of the illness, frequency of the episodes, characteristic/color of the contents, associated abdominal pain, and any precipitating factors including trauma, recent illness, and medication. Protracted or intermittent vomiting can imply an underlying anatomic lesion. Pyloric stenosis should be considered in any infant age 2 to 6 weeks with vomiting. Bilious vomiting in an infant raises suspicion for bowel obstruction, especially malrotation, with or without a volvulus. Vomiting associated with persistent, severe, or localized abdominal pain suggests peritonitis. Bloody vomiting usually involves a lesion proximal to the ligament of Treitz. Vomiting accompanied by a headache or altered mental status raises the possibility increased intracranial pressure and may present with cranial suture splitting and/or bulging anterior fontanelle. Metabolic abnormalities due to inborn error of metabolism (occurring usually in infancy), diabetic ketoacidosis, uremia, and hyper or hyponatremia can also present with vomiting and altered mental status.1–4
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Table 70-1 lists some life-threatening causes of vomiting.
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Diarrhea is defined as frequent loose or liquid bowel movements, three or more per day. The most common cause of diarrhea in children is acute infectious gastroenteritis. The history regarding diarrhea should focus on the characteristics of bowel movements (duration, frequency, and ...