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Legionellosis medical therapy

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Pharmacologic medical therapy is indicated in Legionnaires’ disease. The preferred regimens for both mild and moderate-to-severe pneumonia include either azithromycin or a fluoroquinolone. Patients who develop legionellosis-related complications may require other or additional pharmacologic agents. Pontiac fever is self-limited and may be treated with symptomatic therapy only.

Medical Therapy

Antimicrobial Regimen

  • 1. Atypical pneumonia (Legionnaires’ disease)[1]
  • 1.1 Mild pneumonia, non-immunocompromised (inpatient or outpatient)
  • Preferred regimen (1): Azithromycin 500 mg PO qd for 3-5 days
  • Preferred regimen (2): Levofloxacin 500 mg PO qd for 7-10 days
  • Preferred regimen (3): Ciprofloxacin 500 mg PO bid for 7-10 days
  • Preferred regimen (4): Moxifloxacin 400 mg PO qd for 7-10 days
  • Preferred regimen (5): Clarithromycin 500 mg PO bid for 10-14 days
  • Alternative regimen (1): Doxycycline 200 mg PO loading dose THEN 100 mg PO bid for 10-14 days
  • Alternative regimen (2): Erythromycin 500 mg PO qid for 10-14 days
  • Note: Patients with mild disease may be treated entirely with oral therapy
  • 1.2 Moderate to severe pneumonia or immunocompromised
  • Preferred regimen (1): Azithromycin 500 mg PO/IV q24h for 5-7 days
  • Preferred regimen (2): Levofloxacin 500 mg PO/IV q24h for 7-10 days OR 750 mg PO/IV q24h for 5-7 days
  • Alternative regimen (1): Ciprofloxacin 750 mg PO bid for 14 days
  • Alternative regimen (2): Moxifloxacin 400 mg PO qd for 14 days
  • Alternative regimen (3): Erythromycin 750-1000 mg IV q6h for 3-7 days THEN 500 mg PO qid for a total course of 21 days
  • Alternative regimen (4): Clarithromycin 500 mg IV q12h for 3-7 days THEN 500 mg PO bid for a total course of 21 days
  • Note: Severely ill patients parenteral therapy is advised until improvement is seen and oral absorption is sufficient.
  • 2. Pontiac fever[2]
  • Pontiac fever is febrile, self-limited form of Legionella infection which requires only symptomatic therapy, such as analgesics for headache. Antibiotics are not indicated.
  • 3. Endocarditis[3]
  • Preferred regimen (1): Levofloxacin 750 mg PO/IV qd for 7-10 days AND Rifampin 300 mg PO bid for 4-6 weeks
  • Preferred regimen (2): Moxifloxacin 400 mg PO/IV qd for 7-10 days AND Rifampin 300 mg PO bid for 4-6 weeks

References

  1. Bennett, John (2015). Mandell, Douglas, and Bennett’s principles and practice of infectious diseases. Philadelphia, PA: Elsevier/Saunders. ISBN 978-1455748013.
  2. Bartlett, John (2012). Johns Hopkins ABX guide : diagnosis and treatment of infectious diseases. Burlington, MA: Jones and Bartlett Learning. ISBN 978-1449625580.
  3. Bartlett, John (2012). Johns Hopkins ABX guide : diagnosis and treatment of infectious diseases. Burlington, MA: Jones and Bartlett Learning. ISBN 978-1449625580.


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