Management of Leptospirosis
For mild to moderate leptospirosis, initiate doxycycline 100 mg orally twice daily for 7 days immediately upon clinical suspicion; for severe disease, use ceftriaxone 2g IV daily for 7 days without waiting for laboratory confirmation. 1, 2
Immediate Assessment and Treatment Initiation
Start antibiotics immediately upon clinical suspicion—do not wait for serological confirmation, as delay increases mortality and serology is often negative in the first week. 1, 3
Key Clinical Features to Identify:
- Exposure history: Contact with flood water, contaminated fresh water, or animals (rats, cattle, dogs) within the past 2-20 days 1, 4
- Characteristic symptoms: Biphasic course with high fever (≥39°C), severe calf myalgias, and headache 1, 3
- Pathognomonic sign: Conjunctival suffusion (highly suggestive) 1, 3
- Severe disease indicators: Jaundice, hemorrhage, hepatomegaly, respiratory distress, or hypoxemia 1, 3
Antibiotic Treatment Algorithm
Mild to Moderate Disease (Outpatient):
- First-line: Doxycycline 100 mg orally twice daily for 7 days 1, 5
- Alternatives: Amoxicillin or tetracycline if doxycycline unavailable 1
- Expected response: Clinical improvement within 3 days 1
Severe Disease (Hospitalized):
- First-line: Ceftriaxone 2g IV daily for 7 days 1, 2, 6
- Alternative: Penicillin G 1.5 million units IV every 6 hours for 7 days 1, 2
- Timing critical: Start within 1 hour of recognition—each hour of delay increases mortality 1
- Duration: Standard 7 days, extend to 10 days if slow clinical response 1
Ceftriaxone offers advantages over penicillin: once-daily dosing, broader spectrum coverage, and equal efficacy with potentially superior convenience and safety profile 2, 6, 7
Supportive Care for Severe Disease
Fluid Resuscitation:
- Aggressive IV fluid therapy with isotonic crystalloid or colloid up to 60 mL/kg as three boluses of 20 mL/kg, reassessing after each bolus 1
- Target: Systolic BP >90 mmHg in adults, normal heart rate and BP in children 3
- Monitor closely: Watch for crepitations indicating fluid overload or cardiac dysfunction 3
ICU Admission Criteria:
- Persistent/worsening tissue hypoperfusion despite initial fluid resuscitation 3
- Repeated fluid boluses required or signs of circulatory failure 1
- Respiratory complications requiring mechanical ventilation 1
Adjunctive Therapy:
- Methylprednisolone 0.5-1.0 mg/kg IV daily for 1-2 weeks for respiratory complications 1
Diagnostic Workup (Do Not Delay Treatment)
Initial Laboratory Tests:
- Blood cultures (ideally within first 5 days, before antibiotics if no significant delay <45 minutes) 1, 3
- Complete blood count, comprehensive metabolic panel, urinalysis 1
- Expect: Leukocytosis, proteinuria, hematuria, elevated bilirubin with mild transaminase elevation 3
Confirmatory Testing:
- IgM ELISA: Titer >1:320 diagnostic; 1:80-1:160 consistent with early infection 1, 3
- Convalescent serology (MAT): Repeat >10 days after symptom onset; fourfold increase confirms diagnosis 1, 3
Special Populations
Children <8 Years:
- Avoid doxycycline due to permanent tooth discoloration risk 1
- Use: Penicillin or ceftriaxone instead 1
Pregnant Women:
Prophylaxis (High-Risk Settings Only)
- Doxycycline 200 mg single dose orally provides 76.8% protection for post-flood exposure 1
- Reserve for high-risk settings; not for routine use 1
Critical Pitfalls to Avoid
- Do not wait for serological confirmation before starting antibiotics 1, 3
- Do not mistake for viral hepatitis in patients with fever and jaundice—consider leptospirosis in differential 1, 3
- Do not discontinue antibiotics early despite clinical improvement—complete full 7-day course 1
- Do not use urine for culture—not suitable for leptospira isolation 1
- Do not delay treatment beyond 4 days of symptoms—efficacy decreases significantly 1