title: Torsades de pointes following clarithromycin treatment.
abstract: A 75-year-old woman presenting with pre-syncope, shortness of breath and nausea was admitted to the emergency department following treatment with clarithromycin. Shortly after admission she developed a prolonged QT interval leading to torsades de pointes (TdP) and cardiac arrest. She was successfully cardioverted and clarithromycin was discontinued resulting in restoration of her usual QT interval. This case is an example of acquired long QT syndrome; a disorder that can be precipitated by macrolide antibiotics such as clarithromycin. Additional risk factors present in this case include: female gender, old age, heart disease, hypokalemia and hypomagnesemia. In this manuscript we comprehensively review past cases of clarithromycin-induced long QT syndrome (LQTS) and discuss them within the context of this case.
authors.affiliation: Department of Medicine, Kingston General Hospital, Queen's University, Kingston, Ontario, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Gysel
authors.forename: W Victor R
authors.initials: WV
authors.lastname: Vieweg
authors.forename: Mehrul
authors.initials: M
authors.lastname: Hasnain
authors.forename: Jules C
authors.initials: JC
authors.lastname: Hancox
authors.forename: Vitharani
authors.initials: V
authors.lastname: Kunanithy
authors.forename: Adrian
authors.initials: A
authors.lastname: Baranchuk
mesh_terms: D000367:Age Factors; D000368:Aged; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use; D017291:Clarithromycin / Q000009:adverse effects* / Q000627:therapeutic use; D004554:Electric Countershock / Q000379:methods; D005260:Female; D006323:Heart Arrest / Q000139:chemically induced; D006801:Humans; D008133:Long QT Syndrome / Q000139:chemically induced*; D012307:Risk Factors; D012737:Sex Factors; D016171:Torsades de Pointes / Q000139:chemically induced*
chemical_list: D000900:Anti-Bacterial Agents; D017291:Clarithromycin