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An evaluation strategy for potential QTc prolongation with chronic azithromycin therapy in cystic fibrosis

Patrick John Lenehan1, Craig M Schramm2, Melanie Sue Collins2

  • 1Medical Scientist Training Program, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115, USA.

Journal of Cystic Fibrosis : Official Journal of the European Cystic Fibrosis Society
|December 25, 2015
PubMed

Insights

Chronic azithromycin therapy in cystic fibrosis (CF) patients may increase QTc intervals, especially in adolescent males. Cardiac monitoring is recommended for CF patients undergoing long-term azithromycin treatment.

Area of Science:

  • Cardiology
  • Pulmonology
  • Pharmacology

Background:

  • Chronic azithromycin is standard for cystic fibrosis (CF) patients with persistent Pseudomonas aeruginosa.
  • Macrolide antibiotics can cause QT prolongation, but azithromycin's cardiac effects in pediatric CF are understudied.

Purpose of the Study:

  • To analyze QTc interval changes in pediatric CF patients starting chronic azithromycin therapy.

Main Methods:

  • Retrospective analysis of QTc intervals before and after azithromycin initiation in pediatric CF patients.

Main Results:

  • Adolescent males demonstrated increased QTc intervals following the commencement of azithromycin therapy.

Conclusions:

  • Azithromycin may affect the QTc interval in pediatric CF patients, particularly adolescent males.
  • Monitoring QTc intervals is advisable for CF patients on chronic azithromycin due to potential cardiac implications.

Keywords:
AzithromycinCystic fibrosisMacrolideQTc intervalQTc prolongation

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