ED Management: 35-Year-Old Male, Acute Traveler's Diarrhea (10-15 stools/day x 2 days)

1. Initial Assessment - Triage Priorities

• Travel destination (high-risk: South Asia, West/Central Africa; lower risk: Latin America, SE Asia)
• Stool character: watery vs. bloody/mucoid (dysentery vs. secretory)
• Fever, tenesmus, severe abdominal pain (suggest invasive pathogen)
• Fluid intake vs. output estimate
• Comorbidities: immunosuppression, IBD, renal failure, DM
• Recent antibiotics (C. difficile risk)
• Food/water exposures (untreated water, raw foods, ice)

10-15 episodes/day = severe by functional impact. Antibiotics are indicated.

2. Physical Examination

• Vital signs: tachycardia, hypotension (orthostatic), fever
• Skin turgor, mucous membranes
• Mental status (severe dehydration indicator)
• Capillary refill time
• Abdominal exam: distension, tenderness, peritoneal signs

3. Investigations

• Point-of-care blood glucose
• Capillary ketones if clinically indicated
• ECG if tachycardic/hypotensive

• CBC (leukocytosis suggests bacterial/invasive)
• CMP/RFT (urea, creatinine, electrolytes - Na, K, HCO3)
• LFTs if febrile or prolonged travel illness
• Blood cultures if febrile and toxic appearance

• Stool culture for Salmonella, Shigella, Campylobacter, E. coli O157:H7
• Shiga toxin assay
• Microscopy or antigen assay for E. histolytica
• If exposure to untreated water or illness >7 days: add Giardia antigen, Cryptosporidium antigen by EIA

Routine stool cultures are rarely necessary for uncomplicated traveler's diarrhea, but given the severity (10-15 stools/day) and travel history, targeted cultures are warranted. - Tintinalli's EM

4. Rehydration - Immediate Priority

• ORS (WHO formula or commercial): Ceralyte 90, Pedialyte, Gatorade
• Alternatively: chicken broth + fruit juice + non-caffeinated fluids
• Diet: complex carbohydrates (bananas, rice, bread, potatoes, crackers)
• Lactobacillus-containing yogurt is acceptable

• Unable to tolerate oral fluids (persistent vomiting)
• Signs of moderate-to-severe dehydration: HR >100, orthostatic hypotension, dry mucous membranes, poor turgor
• Altered mental status
• Electrolyte disturbances on labs (hypokalemia common with high-volume diarrhea)

5. Antibiotic Therapy

First-line (current recommendation, Rosen's EM 2024):

Fluoroquinolones (Ciprofloxacin):

• No longer first-line due to widespread resistance and increased risk of MDR organisms
• If used: 500 mg PO BID or 750 mg once daily x 1-3 days
• Growing fluoroquinolone resistance especially in South/Southeast Asia (Campylobacter)

"Fluoroquinolones are no longer the first line antibiotic choice for treatment of traveler's diarrhea due to widespread resistance." - Rosen's EM

6. Antimotility Agents

• 4 mg initially, then 2 mg after each unformed stool
• Maximum 16 mg/day; use for no more than 2 days
• Combine with antibiotics in severe cases
• Avoid in dysentery (bloody stools, fever) - increases toxin contact time

• 30 mL or 2 tablets q30 min x 8 doses; can repeat Day 2
• Caution: avoid in aspirin allergy, HIV patients (bismuth encephalopathy risk)

7. Antiemetics

• Ondansetron (metoclopramide as alternative) if nausea/vomiting is preventing oral rehydration
• Ondansetron 4-8 mg IV/PO; may increase stool frequency but reduces need for IV rehydration

8. Likely Causative Pathogens by Travel Region

9. Disposition

10. Discharge Instructions & Prevention Counseling

• Complete antibiotic course
• Maintain oral hydration with ORS
• BRAT-type diet initially (bananas, rice, applesauce, toast)
• Hand hygiene: frequent hand washing
• Food safety: "Peel it, boil it, cook it, or forget it"
• Avoid raw produce, dairy, ice, tap water
• Return precautions: high fever, bloody stools, symptoms worsening or not improving within 48 hours, signs of dehydration

Quick Summary Algorithm

Arrive in ED → Assess vitals + dehydration
      ↓
IV access + bloods (CBC, CMP, BG) + stool studies
      ↓
Can tolerate PO?
  YES → ORS + loperamide + azithromycin 500mg PO x 3 days → Observe 1-2h → Discharge
  NO  → IV fluids (NS/RL) + IV antiemetic + azithromycin 500mg PO (or IV if not absorbing) 
      ↓
Bloody stools or fever >38.5°C?
  YES → Avoid loperamide; culture-directed therapy; consider admission
  NO  → Loperamide safe to use
      ↓
Re-assess after 1-2 hours of rehydration → Discharge if improving

• Tintinalli's Emergency Medicine: A Comprehensive Study Guide (9th ed.) - Chapter on Acute Infectious and Traveler's Diarrhea
• Rosen's Emergency Medicine: Concepts and Clinical Practice - Chapter 80, Traveler's Diarrhea