Calcific Changes in an End-Stage Kidney following Long-Term Dialysis, Tertiary Hyperparathyroidism, and Treatment for...

Area of Science:

• Nephrology
• Pathology
• Immunology

Background:

• Glomerular calcification is infrequently described in end-stage kidney disease (ESKD).
• Limited data exist on long-term outcomes for complement-mediated thrombotic microangiopathy (CM-TMA) treated with complement factor 5 inhibitors (C5i).
• CM-TMA, previously known as atypical hemolytic uremic syndrome, can be associated with complement factor I (CFI) mutations.

Purpose of the Study:

• To report a case of ESKD from CM-TMA with tertiary hyperparathyroidism and unusual glomerular calcification.
• To discuss the implications of long-term C5i treatment in a patient with a CFI mutation and CM-TMA.
• To explore potential pathogenetic mechanisms of glomerular calcification in this context.

Main Methods:

• Case report detailing a patient with ESKD due to CM-TMA.
• Description of histological findings from nephrectomy, including glomerular calcification.
• Review of long-term treatment with C5i for CM-TMA and associated tertiary hyperparathyroidism.

Main Results:

• The patient presented with ESKD, CM-TMA, and tertiary hyperparathyroidism, treated with C5i for cerebral symptoms.
• Nephrectomy revealed diffuse glomerular calcification and focal arterial/tubular basement membrane calcification.
• Chronic TMA persisted with C5i treatment, indicating quiescent systemic TMA activity.

Conclusions:

• Glomerular calcification in this ESKD case is rare and its etiology (hyperparathyroidism or other mechanisms) is unclear.
• Long-term C5i treatment may be beneficial for patients with pathogenic CFI mutations and CM-TMA.
• The findings suggest potential benefits of sustained complement inhibition for managing CM-TMA associated with CFI mutations.