We have attentively read the letter to the editor by Dr. Sánchez Luque, with respect to the absence of the Roussel-Uclaf hepatotoxicity causality assessment method (RUCAM) in our study. Unfortunately, all the variables required for completing the latest version of that scoring method were not available in all the cases we studied.1 We compiled our study population from a database of histopathologic reports of liver samples, not from the viewpoint of the treating clinicians. Thus, added to the limitations inherent in retrospective studies, data, such as the course of ALT levels at 180 days of follow-up and all the tests for determining alternate causes, were not available for the majority of cases. Likewise, the specific question about previous reactions to a given drug or substance, involving liver damage, or re-exposures to those agents, were not reported in the clinical histories of each patient.

Therefore, had we calculated the score of the RUCAM in our cases, the result would inevitably have been erroneous and most likely lower than the hypothetically real one, in turn, leading to disinformation about the accuracy of the tool for analyzing such cases. As Dr. Sánchez Luque correctly pointed out, the accuracy of the RUCAM is very high, but requires a level of quality and checklist that are not always available in retrospective studies.