Informativeness of patient initial reports of adverse drug reactions. Can it be improved by a pharmacovigilance centre?

PURPOSE: Little is known about the informativeness of initial patient reports before they are reviewed by a pharmacovigilance centre (PVC). We aim to describe the patterns of patient adverse drug reaction (ADR) reporting in France and estimate the contribution of a review by a PVC assessor on the informativeness of these reports. METHODS: A retrospective study was conducted on patient reports between July 2011 and July 2015. Informativeness of 16 key elements of information (including drug start and end date, duration of treatment, time to onset and duration of the ADR, outcome, medical history and concomitant medication) was assessed in initial reports before and after review by a pharmacovigilance assessor. RESULTS: Overall, 240 reports concerning 522 ADR and involving 278 drugs were reported over this 4-year period. Mean number of available key elements of information in initial reports was increased from 11/16 to 15/16 after review of reports by the PVC. Time to onset and duration of the ADR were respectively available in only 51 and 58% of the reports before review compared to 83 and 90% after review. Medical history and concomitant medication were missing in 75% of the initial reports compared to less than 30% of the reports after review. Contacting the reporter enabled an increase of informativeness of most elements of information for more than 90% of the reports. CONCLUSION: Patient reports often need to be completed on key elements of information that are required to assess reports. Both upstream education of patients and downstream intervention of a pharmacovigilance assessor to complete missing information could help to enhance the informativeness of such reports.

[Drug patch tests in the investigation of a fixed drug eruption subsequent to 2 courses of cyclophosphamide in combination with mesna]. / Tests épicutanés pour un érythème pigmenté fixe après prise de cyclophosphamide associé au mesna.

BACKGROUND: When fixed drug eruption occurs following use of cyclophosphamide and mesna, it is difficult to establish which drug is responsible. We report a new case of patch tests that resulted in withdrawal of mesna and enabled continued treatment with cyclophophamide. PATIENTS AND METHODS: A 57-year-old female patient with multiple sclerosis presented increasingly severe cutaneous lesions after successive courses of cyclophosphamide. Twenty-four hours after her latest treatment, she presented at the ER with a worse eruption than those to date and including facial lesions. The clinical diagnosis was a fixed drug eruption, and patch tests for mesna one month later were positive. CONCLUSION: Fixed drug eruption always occurs after recurrent treatment and the investigation must be precise. Patch tests may be used to determine which drug could be responsible. The most conclusive test comprises withdrawal of the incriminated drug with no further signs of drug eruption on resumption of the other medication.