What is the recommended management for dysentery?

Dysentery Management

Azithromycin is the first-line antibiotic for empiric treatment of dysentery, given as either a single 1000 mg dose or 500 mg daily for 3 days, combined with aggressive oral rehydration therapy. 1

Initial Assessment and Rehydration

The cornerstone of dysentery management is immediate assessment of hydration status and fluid replacement, which takes priority over antimicrobial therapy in preventing mortality. 1

Hydration Protocol

• Reduced osmolarity oral rehydration solution (ORS) is first-line therapy for mild to moderate dehydration 1
• For severe dehydration (≥10% fluid deficit), shock, or altered mental status: administer isotonic intravenous fluids (lactated Ringer's or normal saline) immediately 1
• Nasogastric ORS administration at 15 mL/kg/hour can be used for patients unable to drink but not in shock 1
• Continue rehydration until pulse, perfusion, and mental status normalize, then transition to ORS for remaining deficit 1

Antimicrobial Therapy

First-Line Treatment: Azithromycin

Azithromycin should be considered the first-line agent for all cases of dysentery due to widespread fluoroquinolone resistance, particularly in Campylobacter species, and its effectiveness against Shigella, enteroinvasive E. coli, Aeromonas, Plesiomonas, and Yersinia enterocolitica. 1, 2

Dosing options:

• Single 1000 mg dose (preferred for simplicity and adherence) 1
• 500 mg daily for 3 days 1, 2

Alternative Agents

Fluoroquinolones may be used for severe non-dysenteric diarrhea but have reduced efficacy in dysentery due to resistance patterns: 1

• Ciprofloxacin 500 mg twice daily for 3 days 1, 3
• Levofloxacin 500 mg daily for 3 days 1, 2

Important caveat: Fluoroquinolone resistance exceeds 90% for Campylobacter in Southeast Asia and is increasingly problematic globally, making them suboptimal for empiric dysentery treatment. 1

Rifaximin should NOT be used for dysentery as it is ineffective for invasive diarrheal illness. 1, 2

Pathogen-Specific Considerations

For confirmed Shigella dysentery (when local susceptibility patterns are known): 1

• First-line: Ciprofloxacin, ceftriaxone, or pivmecillinam (cure rate >99%) 3
• If resistant to first-line agents: Nalidixic acid (55 mg/kg/day in 4 divided doses for 5 days) or tetracycline (50 mg/kg/day in 4 divided doses for 5 days) 1
• Change antibiotic if no clinical response within 2 days 1

For suspected amebic dysentery: Stool microscopy should identify Entamoeba histolytica trophozoites; treat with appropriate antiprotozoal therapy if confirmed. 1, 4

Critical Management Principles

What NOT to Do

• Avoid antimicrobials in Shiga toxin-producing E. coli (STEC) O157 and other STEC producing Shiga toxin 2, as antibiotics may precipitate hemolytic uremic syndrome 1
• Do not use antimotility agents (loperamide) in children <18 years with dysentery 1
• Avoid loperamide in adults with dysentery if symptoms worsen or fever develops 1
• Do not delay feeding—resume age-appropriate diet immediately after rehydration 1

Diagnostic Approach

• Stool cultures are indicated for dysentery to guide antimicrobial therapy 1
• Visual stool examination should confirm blood and mucus presence 1
• Microscopy can distinguish E. histolytica trophozoites from white blood cells (a nonspecific indicator of dysentery) 1
• A single fecal sample is sufficient for etiologic diagnosis in most cases 4

Nutritional Management

• Continue breastfeeding throughout the diarrheal episode in infants 1
• Resume normal diet immediately after rehydration—there is no justification for "bowel rest" through fasting 1
• Energy-rich, easily digestible foods help maintain nutritional status 1

Special Populations

Immunocompromised patients and ill-appearing young infants may warrant empiric antimicrobial therapy even without confirmed dysentery. 1

Asymptomatic contacts should NOT receive empiric or preventive antimicrobial therapy, but should follow infection prevention measures. 1

Common Pitfalls to Avoid

• Do not wait for culture results to initiate treatment in clinically evident dysentery—empiric azithromycin should be started immediately after specimen collection 1
• Do not use single-dose fluoroquinolones for dysentery—if fluoroquinolones are used, give full 3-day course 1
• Do not assume all bloody diarrhea requires antibiotics—STEC must be excluded first 1
• Reassess hydration status after 3-4 hours and adjust fluid therapy accordingly 1