[An analysis of the causes, characteristics, and consequences of reexposure to a drug or compound responsible for a hepatotoxicity event]. / Análisis de las causas, características y consecuencias de la reexposición al fármaco o compuesto responsable de un episodio de hepatotoxidad.

INTRODUCTION: reexposure to a causal agent represents a potentially serious event in hepatotoxicity. OBJECTIVES: to assess the characteristics and outcome of cases with positive reexposure. MATERIAL AND METHODS: a retrospective study of cases with evidence of positive reexposure included in Registro Español de Hepatopatías Asociadas a Medicamentos, and an analysis of their relation to demographic and clinical variables, causality, course, and consequences. RESULTS: of a total of 520 cases 31 (6%) met reexposure criteria. Fatal outcomes, needs for admission, and mean recovery time were all higher for hepatocellular-type toxic injury. The most commonly identified drug class was antibiotics. On most occasions (73%) reexposure to the causal compound escaped notice because of: absence of index case diagnosis, lack of information to patients and their physicians, and (12%) development of cross reactions between structurally similar drugs. CONCLUSIONS: accidental reexposure to a drug or a structurally-related compound after an initial hepatotoxicity event is common and may have serious consequences, particularly in hepatocellular-type toxicity. Careful history taking and reflecting diagnostic suspicion in the initial episode s record may reduce the incidence of this iatrogenic event.