What is the recommended treatment for leptospirosis?

Treatment of Leptospirosis

For leptospirosis treatment, antibiotics should be started immediately upon clinical suspicion, with penicillin or doxycycline for mild to moderate cases and intravenous penicillin for severe cases (Weil's disease), without waiting for laboratory confirmation. 1, 2

Classification and Clinical Presentation

• Leptospirosis presents as two main clinical forms: mild to moderate (flu-like symptoms) and severe form (Weil's disease) characterized by hemorrhage, jaundice, and hepato-renal failure 1, 3
• The septicemic or bacteremic phase lasts 4-7 days with high fever, diffuse myalgias (especially in calves), headache, and conjunctival suffusion 1
• Conjunctival suffusion is a suggestive clinical sign that should prompt consideration of leptospirosis 3

Treatment Algorithm Based on Disease Severity

Mild to Moderate Leptospirosis

• Start antibiotics as soon as possible upon clinical suspicion 1, 2
• Preferred options:
  • Doxycycline 100 mg orally twice daily for 7 days 1, 4
  • Amoxicillin 500 mg orally three times daily for 7 days 4
  • Penicillin oral formulations are also effective during the bacteremic phase 2

Severe Leptospirosis (Weil's Disease)

• Immediate hospitalization and antibiotic treatment without waiting for laboratory confirmation 1, 2
• Preferred options:
  • Intravenous penicillin G 1.5 million units every 6 hours for 7 days 1, 4
  • Intravenous ceftriaxone 1-2 g daily for 7 days 4
• Standard course is 7 days but may need extension to 10 days in patients with slow clinical response 1

Special Populations

• For children under 8 years, penicillin or amoxicillin should be used instead of doxycycline due to potential effects on bone and teeth development 2
• For pregnant patients, penicillin is the safest option 2

Timing of Treatment

• Early antibiotic administration is critical - treatment initiated after 4 days of symptoms may be less effective 1
• Treatment should begin in the bacteremic phase for maximum benefit 2, 5
• Do not discontinue antibiotics early; complete the full course even with clinical improvement 1

Supportive Care

• Fluid resuscitation targeting systolic blood pressure >90 mmHg in adults 1
• Continuous monitoring for patients with severe disease, especially for development of renal failure 1, 6
• Patients with severe manifestations may deteriorate rapidly despite antibiotic treatment and may require renal or hepatic support 2

Important Considerations

• The benefit of antibiotic therapy may be limited in the late immune-mediated phase of severe disease 2, 7
• A Cochrane review showed insufficient evidence for or against antibiotics in leptospirosis, though treatment may decrease duration of illness by 2-4 days 7
• Despite this uncertainty, clinical guidelines still strongly recommend early antibiotic treatment based on observational data and clinical experience 1, 2

Common Pitfalls

• Delaying treatment while waiting for laboratory confirmation significantly increases mortality 1, 5
• Misdiagnosing leptospirosis as viral hepatitis in patients with fever and jaundice 1
• Discontinuing antibiotics too early before completing the full course 1
• Failing to recognize the transition from mild to severe disease, which can occur rapidly 2