The RECAM is a scoring algorithm to aid in the diagnosis of idiosyncratic drug-induced liver injury (DILI). It is an evidence-based update of the RUCAM. Like the RUCAM, the RECAM is designed to give the user a framework for how to assess DILI and provide an estimate of DILI likelihood. The RECAM estimate is based on iterative testing of cases from the US Drug-Induced Liver Injury Network (DILIN) and the Spanish DILI Registry. Both registries use expert opinion to assign DILI likelihood, and the RECAM was designed to best fit those expert opinion assessments.
There are significant differences between the RUCAM and RECAM, but also several similarities. It continues to apply points for clinical data and literature regarding DILI risk of a particular medication. These points are grouped into five domains as opposed to the seven RUCAM criteria. The sum of the 5 Domain scores are grouped into categories of DILI likelihood similar to RUCAM, but the range of scores is wider. RECAM minimizes subjective input and need for calculation by the user to increase inter-rater reliability. We designed each website page to have clear data entry fields with drop down menus and calendars wherever possible. Domain 4 in particular uses drop down choices for tests results that assess the most common competing diagnoses.
While the ability to approximate expert opinion at various diagnostic likelihood cut-offs is quite good with AUCs in the 0.85 to 0.95 range, the RECAM should never be used as a standalone diagnostic. It is not a substitute for good clinical judgement. The heterogeneity of DILI and individual patient idiosyncrasies does not allow for a single, diagnostic scoring algorithm that fits all cases. Each case of suspected DILI may carry unique characteristics and nuances that cannot be captured by RECAM.
There are other specific limitations and cautions on the use of the RECAM.
- The RECAM is designed for acute liver injury. Therefore, the user should rule-out non-liver sources for enzyme and bilirubin elevations (e.g., muscle injury, hemolysis, bone disease) before using RECAM.
- RECAM is designed for idiosyncratic drug injuries. It was not designed for direct hepatotoxins like acetaminophen. The diagnosis of acetaminophen liver injury relies on other data such as drug levels and history of overdose. RECAM should not be used for these types of injuries.
- RECAM is not designed to weigh one medication against another in a patient who may have taken multiple suspected medications. This is distinctly different from RUCAM. Therefore, users must score individual medications separately and then decide which medication is more likely by using clinical judgement and the individual drug scores.
- Like the RUCAM, RECAM was built using DILI cases due to medications, not herbal or dietary supplements. Therefore, users should use the RECAM for suspected HDS liver injury with caution.
- The RECAM is based on the DILIN and Spanish Registries which have minimum liver test requirements for case enrollment (e.g., transaminases >5 times upper limit of normal). Therefore, it is unclear how RECAM will perform for less severe enzyme elevations.
- RECAM is not based on nor designed for pre-market, clinical trials or drug development where consensus expert opinion is preferred.