Defining Severe Acute Diarrhea

Clinical Features Defining Severity

The presence of bloody or mucoid stools indicates invasive bacterial infection or inflammatory process, according to the Infectious Diseases Society of America 1, 3
Documented fever (≥38.5°C) in a medical setting, especially with signs of sepsis, is a key warning sign, as recommended by the Infectious Diseases Society of America 1
Severe abdominal cramping or tenderness suggests possible complications like toxic megacolon or perforation, as noted by the American Society of Clinical Oncology 4
Signs of sepsis, including tachycardia, hypotension, or altered mental status, are critical indicators of severity, according to the Infectious Diseases Society of America and the American Society of Clinical Oncology 1, 2
Moderate to severe dehydration requiring intravenous fluid resuscitation is a key indicator of severity, as recommended by the American Society of Clinical Oncology 2

Immunocompromised individuals require a lower threshold for defining severity and should receive empiric antimicrobial treatment even with less dramatic presentations, according to the Infectious Diseases Society of America 1
Neutropenic patients with diarrhea and fever warrant immediate hospitalization and broad-spectrum antibiotics covering gram-negative, gram-positive, and anaerobic organisms, as recommended by the American Society of Clinical Oncology 2, 4

Toxic megacolon detected by abdominal imaging is a life-threatening complication, as noted by the American Society of Clinical Oncology 4
Intestinal perforation identified on plain abdominal X-ray is a surgical emergency, according to the American Society of Clinical Oncology 4
Hemolytic-uremic syndrome (particularly with Shigella or STEC infections) is a critical complication, as recommended by the American Society of Clinical Oncology 4
Acute kidney injury with oliguria (<0.5 mL/kg/h) despite adequate volume resuscitation is a severe complication, according to the American Society of Clinical Oncology 2

Patients meeting severity criteria should be hospitalized for close monitoring, intensive treatment, and multidisciplinary evaluation, as recommended by the American Society of Clinical Oncology 2
Rapid fluid resuscitation with initial bolus of 20 mL/kg if tachycardic or potentially septic is critical, according to the American Society of Clinical Oncology 2
Empiric antibiotics are not recommended for most immunocompetent patients with bloody diarrhea, except in cases of documented fever with bacillary dysentery, recent international travel with temperature ≥38.5°C or signs of sepsis, or immunocompromised patients with severe illness and bloody diarrhea, as recommended by the Infectious Diseases Society of America 1