What is the treatment for Weil's disease (Leptospirosis)?

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Treatment of Weil's Disease (Leptospirosis)

Doxycycline is the recommended drug of choice for leptospirosis, with a dosage of 100 mg orally twice daily for 7 days for mild to moderate cases. 1

Clinical Presentation and Diagnosis

Weil's disease is a severe form of leptospirosis characterized by:

  • Fever, headache, chills, myalgia, and a biphasic illness pattern
  • Jaundice and hepatomegaly/splenomegaly
  • Conjunctival suffusion (redness without exudate)
  • Renal involvement
  • Coombs-negative intravascular hemolysis in severe cases
  • Multi-organ failure in advanced cases

Early diagnosis is crucial for improved prognosis and depends on:

  • Clinical features (sudden onset febrile illness, severe malaise, muscle pain)
  • Laboratory findings (proteinuria, leukocytosis with neutrophilia)
  • Epidemiological factors (exposure to contaminated water/soil, animal urine)

Treatment Algorithm

Mild to Moderate Leptospirosis

  • First-line therapy: Doxycycline 100 mg orally twice daily for 7 days 1

Severe Leptospirosis (Weil's Disease)

  • First-line options:
    • Penicillin G: 1.5 million IU IV every 6 hours for 7 days 1
    • Ceftriaxone: 1-2 g IV daily for 7 days 1
    • Ampicillin: 1 g IV every 6 hours for 7 days 1

Special Populations

  • Pregnant patients: Avoid doxycycline; use penicillin G or erythromycin 1

Monitoring and Supportive Care

  • Monitor for Jarisch-Herxheimer reaction (JHR) after antibiotic initiation, which may require vasopressor support in severe cases 2
  • Provide appropriate fluid management and electrolyte correction
  • Consider renal dialysis for severe renal involvement
  • Monitor hepatic function, as jaundice is an independent predictor of severe disease 3
  • Observe cardiac function, as cardiac damage is also predictive of severe disease 3

Important Clinical Considerations

  • Early antibiotic treatment is crucial for improved outcomes
  • Streptomycin has shown excellent bactericidal activity against leptospires in some studies, with aminoglycosides like gentamicin, tobramycin, and isepamicin as effective alternatives 4
  • When using antibiotics with inadequate bactericidal activity, long-term therapy with sufficient doses may be required from early disease stage until antibody appearance 4
  • Patients started on antibiotics should be monitored for potential decompensation due to JHR before discharge or transfer to regular medical floors 2

Prognosis

With appropriate antibiotic treatment, most patients recover without residual organ impairment, even those with severe disease 5. However, untreated Weil's disease can be fatal, with mortality rates of 5-15% in severe cases 1.

References

Guideline

Leptospirosis Diagnosis and Treatment

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

Clinical observation and treatment of leptospirosis.

Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy, 2001

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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