Treatment of Low-Grade Fever with Non-Bloody Diarrhea
In most patients with low-grade fever and non-bloody diarrhea without recent international travel, empiric antimicrobial therapy is not recommended—focus on oral rehydration as the primary treatment. 1
Primary Treatment: Rehydration
Oral rehydration solution (ORS) is the cornerstone of therapy regardless of whether antimicrobials are indicated. The approach depends on hydration status:
Mild to Moderate Dehydration
- Administer reduced osmolarity ORS as first-line therapy for all age groups with 50-100 mL/kg over 3-4 hours for children, or 2-4 L for adults. 1, 2
- Continue ORS until clinical dehydration is corrected, then switch to maintenance fluids to replace ongoing stool losses. 2
- Nasogastric administration of ORS may be used in patients with moderate dehydration who cannot tolerate oral intake or are too weak to drink. 1, 2
Severe Dehydration
- Use isotonic IV fluids (lactated Ringer's or normal saline) when there is severe dehydration, shock, altered mental status, or failure of ORS therapy. 1, 2
- Continue IV rehydration until pulse, perfusion, and mental status normalize, then transition to ORS for remaining deficit replacement. 1, 2
When to Consider Antimicrobial Therapy
The presence of low-grade fever alone does NOT warrant empiric antibiotics in most cases. 1 However, consider empiric antimicrobials in these specific scenarios:
Indications for Empiric Treatment
- Infants <3 months of age with suspected bacterial etiology. 1
- Immunocompromised patients or ill-appearing young infants. 1
- Recent international travelers with fever ≥38.5°C or signs of sepsis. 1
- Clinical features suggesting bacillary dysentery (frequent scant stools, fever documented in medical setting, abdominal pain, tenesmus) presumptively due to Shigella. 1
Empiric Antimicrobial Choices (When Indicated)
- For adults: Ciprofloxacin or azithromycin, depending on local susceptibility patterns and travel history. 1, 3
- For children: Azithromycin preferred, or third-generation cephalosporin for infants <3 months. 1
Nutritional Management
- Resume age-appropriate usual diet immediately during or after rehydration—do not withhold food. 1, 2
- Continue breastfeeding throughout the diarrheal episode in infants. 1, 2
Symptomatic Treatment Considerations
Antimotility Agents
- Loperamide may be used in immunocompetent adults with watery diarrhea once adequately hydrated, but avoid in patients with fever or inflammatory diarrhea due to risk of toxic megacolon. 2, 4
- Never use loperamide in children <18 years of age with acute diarrhea. 2, 4
Antiemetics
- Ondansetron may be given to children >4 years and adolescents with vomiting to facilitate oral rehydration tolerance. 2
When to Modify or Discontinue Treatment
- Discontinue or modify antimicrobials when a specific pathogen is identified through diagnostic testing. 1
- If no clinical improvement occurs within 48 hours, reassess for non-infectious causes and consider alternative diagnoses. 2
- Avoid empiric treatment in persistent watery diarrhea lasting ≥14 days—non-infectious causes predominate in this timeframe. 1
Critical Pitfalls to Avoid
- Never withhold rehydration while pursuing antimicrobial therapy—fluid replacement is always the priority regardless of fever presence. 2
- Do not use antimicrobials routinely for acute watery diarrhea with low-grade fever—most cases are viral or self-limited bacterial infections. 1
- Avoid antimotility agents when fever is present—this suggests inflammatory diarrhea where loperamide increases risk of complications. 2, 4
- Do not assume bacterial infection based solely on low-grade fever—viral gastroenteritis commonly presents with fever and does not benefit from antibiotics. 1
Special Populations
Immunocompromised Patients
- Consider empiric antimicrobial treatment even without high fever or bloody diarrhea in severely immunocompromised individuals. 1
Travelers
- Obtain detailed travel history—recent international travel with fever may warrant empiric treatment even without bloody diarrhea. 1