What is the treatment for Leptospirosis?

Treatment of Leptospirosis

Antibiotic therapy should be initiated promptly upon clinical suspicion of leptospirosis, with penicillin or doxycycline being the first-line treatments, even before laboratory confirmation is available. 1

Clinical Presentation

Leptospirosis presents with a wide spectrum of clinical manifestations, ranging from mild flu-like symptoms to severe disease (Weil's disease) characterized by:

• Initial bacteremic phase (4-7 days):

  • Fever with shivering
  • Diffuse myalgia (especially of calves)
  • Headache
  • "Flu-like" symptoms

• Immune phase (follows 1-3 days later):

  • Fever
  • Myalgia
  • Hepatorenal syndrome
  • Hemorrhage
  • Conjunctival suffusion (a suggestive clinical sign)

Diagnostic Approach

Laboratory findings may include:

• Proteinuria and hematuria on urinalysis
• Polymorphonuclear leukocytosis
• Thrombocytopenia (seen in 65.5% of cases) 2
• Anemia (if significant hemorrhage has occurred)
• Elevated bilirubin with mild elevation of transaminases
• Evidence of renal failure

Diagnostic confirmation methods:

1. Serology: IgM titers >1:320 are suggestive; titers of 1:80-1:160 may indicate early infection
2. Blood cultures: Most useful within first 5 days of onset (before antibiotics)
3. PCR testing: Valuable in early disease when serology may be negative 3

Treatment Algorithm

Mild Disease

• Doxycycline 100 mg orally twice daily for 7 days
• OR Penicillin antibiotics

Severe Disease (Weil's disease with jaundice, renal failure, hemorrhage)

1. Hospitalization with close monitoring
2. Intravenous penicillin G or ceftriaxone
3. Supportive care:
   • Renal support if needed
   • Liver support if needed
   • Management of hemorrhagic complications
   • Respiratory support if ARDS develops

Important Treatment Considerations

• Treatment should be initiated upon clinical suspicion, without waiting for laboratory confirmation 1
• Early treatment during the bacteremic phase is most effective
• Severe disease may still progress despite therapy due to immune-mediated mechanisms
• Patients with jaundice or cardiac involvement should be monitored closely as these are independent predictors of severe disease 2

Prognostic Factors

Two factors independently predict progression to severe leptospirosis:

1. Clinical jaundice
2. Cardiac damage (clinical or ECG evidence) 2

These factors can be identified during initial examination and should prompt more aggressive management.

Prevention

• Avoid contact with potentially contaminated water, especially during recreational activities
• Use protective clothing when occupational exposure is unavoidable
• No person-to-person spread occurs, so no restrictions from contact sports are necessary 1

Common Pitfalls

1. Delayed diagnosis: Leptospirosis often mimics other febrile illnesses, leading to misdiagnosis and delayed treatment 4
2. Relying solely on early serology: Serological tests become positive only 6-10 days after symptom onset; negative early results don't rule out disease
3. Inadequate treatment duration: Short courses may be insufficient; treatment should continue until antibodies appear
4. Failure to recognize severe disease: Patients with jaundice or cardiac involvement require closer monitoring and more aggressive management

While a systematic review mentioned in the guidelines showed no benefit for antibiotic treatment in established leptospirosis based on three trials, most infectious disease specialists continue to recommend antibiotics, acknowledging that severe disease is likely immunologically mediated 1.