Morphologic Features and Clinical Impact of Arteritis Concurrent with Transplant Glomerulopathy

Area of Science:

• Nephrology
• Transplant Immunology
• Pathology

Background:

• Transplant glomerulopathy (cg) is a common complication after kidney transplantation.
• The role of arteritis in the context of cg is not well understood.
• Morphological features and clinical impact of arteritis in cg require further investigation.

Purpose of the Study:

• To investigate the morphology and clinical significance of arteritis in renal allograft biopsies with transplant glomerulopathy.
• To determine the underlying immune mechanisms contributing to arteritis in this context.
• To assess the impact of arteritis on renal allograft survival.

Main Methods:

• Retrospective review of 59 renal allograft biopsies with cg.
• Morphological analysis of arteritis, including Banff classification criteria.
• Immunohistochemistry to identify inflammatory cell infiltrates.
• Clinical correlation with renal allograft survival.

Main Results:

• Concurrent arteritis was identified in 16 of 59 (27%) biopsies with cg.
• Arteritis frequently co-occurred with chronic active antibody-mediated rejection and T-cell-mediated rejection.
• Biopsies with arteritis showed higher inflammation and arterial luminal narrowing.
• Patients with arteritis had significantly shorter renal allograft survival (7.5 vs. 29 months).

Conclusions:

• Arteritis in renal allografts with cg is associated with poor graft survival.
• T-cell-mediated alloimmune responses may contribute to the development of arteritis.
• Antibody-mediated rejection might also play a role in arteritis evolution.
• Arteritis, likely through luminal narrowing, portends a negative prognosis.