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Kidney biopsy codes

Kidney biopsy codes

2025-Aug-08

Kidney Biopsy Codes for nephropathologists

Codes describing both morphological patterns and diagnoses which are required for the study of a non-neoplastic kidney biopsy.

Statement of requirements as initially identified:

  • Define a subset of kidney biopsy codes (KBC) for non-neoplastic kidney biopsies as part of the international release of SNOMED CT

  • Conduct a review of the KBC subset among the nephropathology community

  • Maintain the KBC subset by a multidisciplinary expert group incorporated in the organization of SNOMED CT

  • Establish a system of governance which includes representatives of the major societies related to kidney pathology

Non-neoplastic kidney disorders often lead to chronic kidney disease (CKD), with a major and increasing impact on morbidity and mortality  worldwide.1 In fact, CKD is 10th leading cause of death globally and is expected to become the fifth leading cause of death by 2040 above all cancer types. In contrary to other diseases mortality from chronic kidney disease has not improved but worsened over time. Finally, chronic kidney disease is an expensive disease, which places a heavy burden on health care costs: aggregated health care costs for CKD in Europe are in the range or exceed the costs for diabetes and cancer; this is partly due to expenses for dialysis and transplantation.

In the light of these facts, a correct diagnosis early in the course of the disease is important. In many cases, a kidney biopsy is the method of choice to establish a diagnosis. Reading a biopsy and making a diagnosis can be difficult tasks for pathologists, as many kidney diseases are not well understood. Likewise, patient management can be challenging for the nephrologist, as there often are no evidence-based recommendations for appropriate treatment. Therefore, there is a great need for large patient and biopsy series in order to better understand kidney disease, optimize treatment and care at an early stage. To find and collect these cases, biopsy findings and diagnoses need to be coded using an international coding system.

Existing coding systems (eg. ERA PRD or ICD) often do not provide sufficient granularity for the specific context of kidney biopsy reporting (eg pattern of damage in the kidney important for classification, treatment and prognosis). This is why for example kidney biopsy registries often use proprietary coding systems. These coding systems then unfortunately prevent interoperability and hamper clinical or research collaborations.

Over the last 3 years, a group of pathologists, nephrologists and health IT experts has joined efforts to find a solution to this unmet need: the project “Kidney Biopsy Codes for Pathologists” (KBC in short). The project has generated a coding system containing concepts of both patterns of injury as well as diseases. The concepts are arranged in a multihierachical way with parent-child relations. In order to provide good governance and to promote use within existing frameworks, the KBC team is hoping to collaborate with SNOMED international to achieve a complete and useful clinical subset for this group of diseases in SNOMED CT.

Relevance to International release

Users include pathologists, nephrologists, medical service units, and kidney biopsy registries (stakeholders are close to the KBC project and listed in the publication about kidney biopsy registries from KBC2). Additional users can be research consortia working on kidney biopsy data. Ontologies that correctly describe annotations in digital slides of kidney biopsies with high granularity are a recent need of research projects in the field of artificial intelligence. Biobanks, biobank networks and the pharmaceutical industry are further key users of a coding system such as KBC.

As many kidney diseases are rare diseases, international collaborations are necessary to collect enough cases for various projects. High-ranking research is typically international too. Here, kidney biopsy registries have an important role and need to use an international coding system to achieve interoperability.

All these factors point to the need for KBC to be part of an international project and eventually an international release.

References

  1. Vanholder R, Annemans L, Bello AK, Bikbov B, Gallego D, Gansevoort RT, Lameire N, Luyckx VA, Noruisiene E, Oostrom T, Wanner C, Wieringa F. Fighting the unbearable lightness of neglecting kidney health: the decade of the kidney. Clin Kidney J. 2021 Apr 20;14(7):1719-1730. doi: 10.1093/ckj/sfab070. PMID: 34221379; PMCID: PMC8243275.

  2. Dendooven A, Peetermans H, Helbert M, Nguyen TQ, Marcussen N, Nagata M, Gesualdo L, Perkowska-Ptasinska A, Capusa C, López-Gómez JM, Geddes C, Abdul-Hamid MA, Segelmark M, Yahya R, Garau M, Villanueva R, Dorman A, Barbour S, Cornet R, Hopfer H, Amann K, Leh S; Kidney Biopsy Codes for Pathologists project (www.kibico.org). Coding practice in national and regional kidney biopsy registries. BMC Nephrol. 2021 May 24;22(1):193. doi: 10.1186/s12882-021-02365-3. PMID: 34030637; PMCID: PMC8146626.

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