Successful term pregnancy after renal transplant in end-stage renal disease with complement factor H-related mutation: A case report

Abstract

BACKGROUND

Complement-mediated thrombotic microangiopathy (TMA) is a rare endothelial injury syndrome caused by dysregulated activation of the alternative complement pathway, often linked to genetic abnormalities in complement factor H (CFH), complement factor I, or complement factor H-related (CFHR) proteins. Both renal transplantation and pregnancy are independent triggers for recurrence. This case highlights a genetically high-risk patient who achieved a successful term pregnancy after renal transplantation without complement inhibition, emphasizing individualized risk stratification, close surveillance, and multidisciplinary management for favourable maternal and graft outcomes.

CASE SUMMARY

A 32-year-old woman with end-stage renal disease secondary to genetically confirmed complement-mediated TMA—homozygous CFH exon 17 deletion and CFHR3-CFHR1 duplication—was maintained on dialysis for 2.5 years before undergoing a successful live-donor kidney transplant from her mother. Post-transplant immunosuppression included tacrolimus, mycophenolate mofetil, and prednisolone, later modified to azathioprine during pregnancy planning. One-year post-transplant, she conceived spontaneously. Pregnancy was complicated by transient gestational hypertension, controlled with nifedipine, labetalol, and amlodipine. Proteinuria remained < 150 mg/day; white blood cell counts 5.8-7.2 × 10⁹/L without cytopenia. Serum creatinine ranged 0.9-1.1 mg/dL, and tacrolimus trough levels 5-7 ng/mL. At 36 weeks, she delivered a healthy 3 kg infant by elective caesarean section. Postpartum follow-up at three months confirmed stable maternal and graft function.

CONCLUSION

High-risk complement-mediated TMA patients can achieve successful pregnancy post-transplant through individualized care without mandatory complement blockade.

Keywords: Complement-mediated thrombotic microangiopathy; CFH exon 17 deletion; CFHR3-CFHR1 duplication; Renal transplantation; High-risk pregnancy; Complement dysregulation; Eculizumab-free management; Atypical hemolytic uremic syndrome; Case report

Core Tip: This case highlights a rare instance of successful term pregnancy in a renal transplant recipient with genetically confirmed complement-mediated thrombotic microangiopathy—homozygous complement factor H exon 17 deletion and complement factor H-related (CFHR3-CFHR1) duplication—managed without complement blockade. Despite the dual risk posed by transplantation and pregnancy, careful preconception counseling, immunosuppressive modification, and vigilant multidisciplinary surveillance ensured stable graft function and favorable maternal-fetal outcomes. This report emphasizes individualized, genotype-informed management and adds valuable evidence to guide pregnancy counseling in women with complement dysregulation post-transplant.