What is the treatment for infective diarrhea?

Treatment of Infective Diarrhea

The cornerstone of treatment for infective diarrhea is rehydration therapy with reduced osmolarity oral rehydration solution (ORS), while empiric antimicrobial therapy is NOT recommended for most patients with acute watery diarrhea unless they have specific high-risk features. 1, 2

Rehydration: The Primary Treatment

Mild to Moderate Dehydration

• Reduced osmolarity ORS is first-line therapy for all age groups with mild to moderate dehydration 1, 2
• Administer ORS until clinical dehydration is corrected, then continue to replace ongoing stool losses until diarrhea resolves 1, 2
• If oral intake is not tolerated, consider nasogastric administration of ORS in patients with moderate dehydration who are too weak or refuse to drink 1, 2

Severe Dehydration

• Administer isotonic intravenous fluids (lactated Ringer's or normal saline) immediately for severe dehydration, shock, altered mental status, or when ORS therapy fails 1, 2
• Continue IV rehydration until pulse, perfusion, and mental status normalize 1, 2
• Once stabilized, transition to ORS to replace remaining fluid deficit 1, 2

Nutritional Management

• Continue breastfeeding throughout the diarrheal episode in infants and children 1, 2
• Resume age-appropriate usual diet during or immediately after rehydration - do not withhold food 1, 2
• Routine lactose-free feeds are not necessary, though may reduce diarrhea duration in some cases 3

Antimicrobial Therapy: When to Use and When to Avoid

When Antimicrobials Are NOT Recommended

• Most patients with acute watery diarrhea without recent international travel should NOT receive empiric antimicrobials 1, 2
• Avoid empiric treatment in persistent watery diarrhea lasting ≥14 days 1, 2
• Never use antimicrobials for STEC O157 or other Shiga toxin 2-producing E. coli - this increases risk of hemolytic uremic syndrome 1, 2

When Antimicrobials ARE Indicated

Empiric antimicrobial therapy should be considered for:

• Immunocompromised patients with severe illness 1, 2
• Ill-appearing young infants (<3 months) with suspected bacterial etiology 2
• Patients with fever, abdominal pain, and bloody diarrhea suggesting shigellosis 2
• Recent international travelers with fever ≥38.5°C or signs of sepsis 2
• Suspected enteric fever with sepsis features - treat empirically with broad-spectrum antimicrobials after obtaining blood, stool, and urine cultures 1

Specific Antimicrobial Choices

• Ciprofloxacin is FDA-approved for infectious diarrhea caused by enterotoxigenic E. coli, Campylobacter jejuni, Shigella species, and Salmonella typhi (typhoid fever) 4
• Modify or discontinue antimicrobials once a specific pathogen is identified and susceptibility results are available 1, 2

Adjunctive Therapies

Antimotility Agents

• Never give antimotility drugs to children <18 years with acute diarrhea 2
• Avoid loperamide in inflammatory or febrile diarrhea and bloody diarrhea due to risk of toxic megacolon 2, 5
• Loperamide may be used in immunocompetent adults with acute watery diarrhea only 2

Other Adjunctive Treatments

• Antiemetic agents may be given to children >4 years and adolescents to facilitate oral rehydration when vomiting is present 2
• Probiotic preparations may reduce symptom severity and duration in immunocompetent patients 2, 5

Treatment Algorithm

1. Assess hydration status: Check for orthostatic hypotension, skin turgor, dry mucous membranes, mental status changes 6

2. Assess stool characteristics: Determine if watery vs. bloody, frequency, presence of fever 6

3. Initiate rehydration based on severity:

   • Mild-moderate dehydration → ORS 2
   • Severe dehydration/shock → IV fluids until stabilized, then ORS 2

4. Continue appropriate diet: Do not withhold food; resume normal diet immediately 1, 2

5. Determine if antimicrobials are needed: Only use if patient meets high-risk criteria listed above 1, 2

6. If antimicrobials are indicated: Obtain cultures first when possible, then start empiric therapy and narrow based on results 1

Common Pitfalls to Avoid

• Do NOT neglect rehydration while focusing on antimicrobial therapy - dehydration is the primary threat 2, 6
• Do NOT use antimicrobials routinely for acute watery diarrhea - most cases are viral and self-limited 2, 5
• Do NOT give antimotility agents to children or patients with bloody/inflammatory diarrhea 2
• Do NOT withhold food during diarrheal episodes - early refeeding is recommended 2
• Do NOT use antimicrobials for STEC infections - this worsens outcomes 2
• Do NOT treat asymptomatic contacts - they should follow infection control measures only 1

Special Considerations

• Asymptomatic carriers generally do not need treatment except Salmonella Typhi carriers who may be treated to reduce transmission 2
• If diarrhea persists beyond 14 days, consider non-infectious causes including inflammatory bowel disease and irritable bowel syndrome 2, 6
• Hand hygiene is crucial for prevention, especially after toilet use, diaper changes, and before food preparation 2