Use case 4: Harmonizing coding systems of nephropathology registries with that of the ERA end-stage kidney disease registries 

Previously, the KBC project investigated how kidney biopsy registries code. From this work, it became clear that by lack of a suitable international system for nephropathology, biopsy registries often use either proprietary systems or the ERA PRD coding system (especially in Europe). ² The ERA PRD is the European system for coding in end-stage kidney disease registries. Of note, ERA PRD codes are mapped to SNOMED CT concepts. Although this system seems to work well in clinical contexts (such as the dialysis registries that it was designed for), it does not provide enough granularity for representation of morphology patterns and diagnoses essential to nephropathologists. Moreover, a hierarchical system that would allow the nephropathologist to choose the right disease concept according to the level of clinical information is missing. Clearly, a common coding system used by nephrologists and nephropathologists would facilitate and improve exchange of information concerning nephropathology and clinical nephrology. As this will not be possible we strive for a mapping between KBC terms and ERA PRD codes through SNOMED CT concepts. Aligning KBC terms with SNOMED CT and (histologically proven) PRD codes will enable such improved information exchange.