What is the recommended treatment for leptospirosis?

Leptospirosis Treatment Guidelines

Immediate Treatment Approach

For severe leptospirosis, start intravenous antibiotics immediately upon clinical suspicion without waiting for laboratory confirmation, using either penicillin G (1.5 million units IV every 6 hours) or ceftriaxone (1 g IV daily) for 7 days. 1, 2, 3

Antibiotic Selection by Disease Severity

Severe Leptospirosis (Weil's Disease with jaundice, hemorrhage, renal failure, or neurological involvement):

• First-line options (equally effective):

  • Penicillin G: 1.5 million units IV every 6 hours for 7 days 3
  • Ceftriaxone: 1 g IV daily for 7 days 3
  • Cefotaxime: acceptable alternative 4

• Ceftriaxone may be preferred due to once-daily dosing convenience and broader antimicrobial spectrum, though both agents show equivalent efficacy in reducing fever duration (median 3 days) and mortality (approximately 5% in both groups) 3

• For neurological manifestations (status epilepticus, CNS involvement): Intravenous penicillin or ceftriaxone should be initiated immediately, with IV penicillin traditionally preferred for severe disease 2

Mild to Moderate Leptospirosis (flu-like symptoms without organ failure):

• Doxycycline: 100 mg orally twice daily for 7 days 1, 5
• Doxycycline reduces illness duration by 2 days and effectively treats fever, malaise, headache, and myalgias while preventing leptospiruria 5
• Azithromycin appears promising for less severe disease 4
• Oral penicillin is an alternative 1

Critical Timing Considerations

• Start antibiotics within the first hour of recognizing severe sepsis or septic shock 1
• Treatment initiated after 4 days of symptoms may be less effective, emphasizing the need for early empiric therapy 1
• Never delay treatment while awaiting serological confirmation, as this increases mortality 1, 2

Treatment Duration and Monitoring

• Standard duration: 7 days for all severity levels 1, 5, 3
• Extend to 10 days in patients with slow clinical response 1
• Do not discontinue antibiotics prematurely even with clinical improvement; complete the full course 1
• Reassess antimicrobial regimen daily for potential de-escalation 1

Supportive Care for Severe Disease

Fluid Resuscitation:

• Target systolic blood pressure >90 mmHg in adults with adequate tissue perfusion 1
• Monitor for crepitations indicating fluid overload or cardiac dysfunction during resuscitation 1
• Continuous observation with frequent clinical examinations is mandatory; never leave septic patients alone 1

ICU Admission Criteria:

• Persistent or worsening tissue hypoperfusion despite initial fluid resuscitation 1
• Multiorgan failure (hepato-renal dysfunction, pulmonary hemorrhage, cardiac arrhythmias) 6

Monitoring Requirements:

• Renal function (acute kidney injury is common) 1, 2
• Hepatic function (jaundice with mild transaminase elevation) 1, 2
• Hematologic parameters (thrombocytopenia, anemia from hemorrhage) 1, 2, 6
• Seizure management with antiepileptics if neurological involvement 2

Diagnostic Confirmation

Clinical Suspicion Triggers:

• Fever with chills, diffuse myalgias (especially calves), headache, jaundice, and conjunctival suffusion (highly suggestive sign) 1
• Recent exposure to contaminated water, agricultural work, or flood conditions 1, 7

Laboratory Findings:

• Proteinuria and hematuria 1
• Leukocytosis with polymorphonuclear predominance 1
• Elevated bilirubin with mild transaminase elevation 1
• Thrombocytopenia 6

Serological Confirmation:

• IgM titers >1:320 are diagnostic 1
• IgM titers 1:80-1:160 suggest early infection 1
• Convalescent serology (>10 days after symptom onset) confirms diagnosis 1, 2
• Blood cultures (if obtained within first 5 days before antibiotics) 1

Common Pitfalls to Avoid

• Misdiagnosis as viral hepatitis in patients presenting with fever and jaundice—always consider leptospirosis in the differential 1
• Delaying treatment while awaiting confirmatory testing in severe cases 1, 2
• Using doxycycline for severe disease requiring IV therapy 2
• Inadequate fluid resuscitation leading to persistent hypoperfusion 1
• Premature antibiotic discontinuation before completing 7-day course 1

Prevention Strategies

• Avoid contact with urine from infected animals (rats, cattle, pigs, dogs) 1, 7
• Avoid swimming or wading in potentially contaminated fresh water 7
• Use protective equipment during agricultural work, especially in flooded fields 7
• Exercise heightened caution during floods and in rural agricultural areas with rice production 7