"Striped" pattern of medullary ray fibrosis in allograft biopsies from kidney transplant recipients maintained on tacrolimus

Transplantation. 1999 Feb 15;67(3):484-6. doi: 10.1097/00007890-199902150-00025.


Background: A striped pattern of fibrosis has been described in the kidneys of patients undergoing long-term cyclosporine or tacrolimus therapy. This lesion is frequently misconstrued as being specific for drug toxicity.

Methods: We performed clinicopathologic correlation on 18 patients with striped fibrosis identified by reviewing 61 biopsies from kidney transplant recipients maintained with tacrolimus.

Results: Acute rejection was identified in 14 of 18 patients, chronic rejection in 9 of 18 patients, potential diabetic microvascular injury in 8 of 18, and pre-existing donor disease in 2 of 18. In only one patient could striped fibrosis be ascribed primarily to tacrolimus. Striped fibrosis could also be demonstrated in 6 of 10 late allograft biopsy specimens from patients maintained with only azathioprine, and 8 of 10 native biopsies from patients with advanced diabetes mellitus.

Conclusion: Multiple insults contribute to the pathogenesis of striped fibrosis in the kidney. This lesion can be attributed entirely to chronic drug toxicity in only a minority of allografts.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biopsy
  • Diabetic Nephropathies / surgery
  • Fibrosis
  • Graft Rejection / pathology*
  • Humans
  • Immunosuppressive Agents / therapeutic use*
  • Kidney Failure, Chronic / etiology
  • Kidney Failure, Chronic / surgery*
  • Kidney Medulla / pathology*
  • Kidney Transplantation / immunology*
  • Kidney Transplantation / pathology*
  • Middle Aged
  • Tacrolimus / therapeutic use*
  • Transplantation, Homologous


  • Immunosuppressive Agents
  • Tacrolimus