Recommendations

Key Recommendations

Diagnosis is usually made clinically. Self-limited watery diarrhea, vomiting, or both, with or without fever, malaise, and anorexia, are the hallmark symptoms.

History

Information should be sought about recent contact with people with gastroenteritis, similar symptoms in household contacts, recent travel, and the nature and frequency of stool or vomitus, fluid intake, and urine output. High fever, prolonged diarrhea (lasting >14 days), or severe abdominal pain suggests a nonviral etiology and should be investigated further.[19]

Examination

There may be signs of volume depletion. Tachycardia, dry mucous membranes, hypotension, and altered mental state indicate severe volume depletion.[19]

Abdominal tenderness or blood in the stool may suggest more serious pathology.[19] Vigilance is needed in patients who are older, unusually irritable or drowsy, who have progressive symptoms, or when the diagnosis is uncertain.

Tests

It is not necessary or practical to get blood tests or stool specimens from all patients with gastroenteritis.[20] Stool testing is indicated for patients with moderate to severe, bloody, febrile, dysenteric, nosocomial, or persistent diarrheal illnesses or immunocompromised patients.[20] Blood tests to assess electrolyte status and renal function should be ordered in patients with moderate or severe volume depletion, or patients at higher risk, including older people and patients with comorbidities.[19]

During outbreaks, stool samples should be sought to identify the pathogen as soon as possible to help curtail the outbreak.

Stool viral culture is a definitive diagnostic test, but it is not practical in most cases. Rapid detection is possible with latex agglutination tests, polymerase chain reaction (PCR), microscopy, enzyme immunoassay, or serology, but is usually not necessary.[19] Gastrointestinal panel-based multiplex PCR may facilitate rapid and sensitive diagnosis of viral pathogens, but its impact on clinical outcomes and resource use has yet to be fully established.[20][21][22]

The local health officer should be notified once the outbreak is suspected, and stool samples should be collected to send to the reference lab.

Do not order a comprehensive stool ova and parasite microscopic exam (if considering a parasitic etiology) on patients presenting with diarrhea of less than 7 days’ duration who have no immunodeficiency or no history of living in or traveling to endemic areas where gastrointestinal parasitic infections are prevalent.[23]

Use of this content is subject to our disclaimer