BK Nephropathy

Rare Disease Group

The BK Nephropathy (BKN) Rare Disease Group aims to:

  • collate contemporary information from UK kidney transplant recipients with BK Nephropathy
  • use this information to develop current and relevant information for patients
  • disseminate this information to the renal and transplant communities
  • establish a national consensus to identify recipients at high risk of developing BK Nephropathy
  • develop a recommendation for the optimal screening frequency for the presence of BK viraemia by PCR of peripheral blood
  • produce guidance on the modification of immunosuppressive regimens and use of additional agents to treat BK Nephropathy
  • develop a strategy for patient recruitment to observational and interventional clinical trials

The BK Nephropathy Rare Disease Group is newly formed. The first priority will be using the RaDaR rare disease registry to develop a national dataset from patients with BKN, to include:

  1. Risk factors suggested to be predictive of BKN
  • Demographics, Caucasian ethnicity, presence of diabetes mellitus, delayed graft function, induction treatment, cytomegalovirus infection, immunosuppressive regimen and donor and recipient HLA type).


  1. Diagnosis
  • Timing of onset of BK viraemia and nephropathy relative to transplantation
  • Immunosuppressive doses and drug levels at diagnosis
  • Renal function, including best eGFR posttransplant and eGFR at time of diagnosis
  • Viral load (in copies/ml) – at diagnosis


  1. Management
  • Changes to baseline immunosuppression and introduction of second line agents
  • Response of viraemia and eGFR to change in immunosuppression


  1. Outcome and complications
  • Renal function during modification of immunosuppression, following resolution of viraemia and long term follow up
  • Viral load (in copies/ml) post therapy change (4 weeks, 12 weeks, 6 months, 12 months and thereafter if viraemia persists)
  • Any episodes of rejection – T cell or antibody mediated
  • Graft loss (and cause of failure – whether due to BKN or rejection)
  • Development of ureteral stenosis or urogenital tract malignancy
  • Proteinuria – timing of onset and quantification


  1. Biopsy features
  • Histological characterisation
  • IFTA score on indicative biopsy
  • Dr Catherine Byrne, Consultant Nephrologist, Nottingham
  • Dr Sian Griffin, Consultant Nephrologist, Cardiff RDG Lead
  • Mr Stuart Haines, Patient Representative
  • Dr Rachel Hilton, Consultant Nephrologist, Guy’s Hospital, London
  • Dr Channarayapatna Krishna, Patient Representative
  • Dr Andrew Macdonald, Virologist, School of Molecular and Cellular Biology, Leeds
  • Dr Shafi Malik, Consultant Nephrologist, Leicester
  • Dr Joyce Popoola, Consultant Nephrologist, St George’s, London
  • Dr Rhodri Pyart, Nephrology Trainee, UK Renal Registry, Bristol
  • Ms Sharon Warlow, Transplant Clinical Nurse Specialist, Cardiff
  • Dr Matthew Wellberry Smith, Consultant Nephrologist, St James’, Leeds

The BK Nephropathy Rare Disease Group has not yet applied for any funding to support activities.

Dr Macdonald is in receipt of grant funding from Kidney Research UK and Kidney Research Yorkshire for the study of BK virus.

BK Nephropathy RDG Version 1 updated April 2019 Written by the BK Nephropathy Rare Disease Group


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