ASN's Mission

ASN leads the fight to prevent, treat, and cure kidney diseases throughout the world by educating health professionals and scientists, advancing research and innovation, communicating new knowledge, and advocating for the highest quality care for patients.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on Twitter

Kidney Week

Abstract: PO2234

Comparison of Clinical Features of Pregnant and Non-Pregnant Women with Primary Hyperoxaluria

Session Information

Category: Women’s Health and Kidney Diseases

  • 2000 Women’s Health and Kidney Diseases

Authors

  • Miao, Jing, Mayo Clinic Division of Nephrology and Hypertension, Rochester, Minnesota, United States
  • Mehta, Ramila A., Mayo Clinic Division of Biostatistics, Rochester, Minnesota, United States
  • Norby, Suzanne M., Mayo Clinic Division of Nephrology and Hypertension, Rochester, Minnesota, United States
  • Seide, Barbara M., Mayo Clinic Division of Nephrology and Hypertension, Rochester, Minnesota, United States
  • Andrist, Genia, Mayo Clinic Division of Nephrology and Hypertension, Rochester, Minnesota, United States
  • Milliner, Dawn S., Mayo Clinic Division of Pediatric Nephrology, Rochester, Minnesota, United States
  • Lieske, John C., Mayo Clinic Department of Laboratory Medicine and Pathology, Rochester, Minnesota, United States
  • Kattah, Andrea G., Mayo Clinic Division of Nephrology and Hypertension, Rochester, Minnesota, United States
Background

Primary hyperoxaluria (PH) is a rare monogenic disease characterized by oxalate overproduction in the liver, hyperoxaluria, and risk of kidney stones and chronic kidney disease. Data about the effects of pregnancy on women with PH are lacking. We aimed to compare clinical features and risk of incident kidney failure in women with PH with and without pregnancy.

Methods

Women with PH were identified from the Rare Kidney Stone Consortium registry, and pregnancy was identified by phone interview and medical record review. Kidney survival and risk of time-dependent kidney failure were estimated using the Kaplan-Meier method and adjusted proportional hazard Cox’s model.

Results

We identified 47 women with PH and a history of pregnancy and 39 women without pregnancy. PH was diagnosed later in women with pregnancy vs. women without pregnancy (median age 32.4 vs. 13.4 years, p<0.001). Other clinical characteristics such as PH type, eGFR and 24-hour urine oxalate excretion (U[ox]) at PH diagnosis did not differ between the 2 groups. Fig 1A shows the time course of the PH diagnosis, pregnancy and kidney failure in 29 women with known delivery date. In women with pregnancy versus non-pregnancy, the hazard ratio for incident kidney failure was 0.81 (95% CI 0.25-2.6, p=0.73) when adjusted for PH type, age, and eGFR and U[ox] at PH diagnosis. Among patients with PH1 who did not have kidney failure by the time of the 1st pregnancy (n=20), kidney survival estimates at 10, 20, and 30 years after delivery were 79%, 60%, and 45%, respectively (Fig 1B).

Conclusion

These results suggest that pregnancy did not greatly impact renal prognosis in women with PH.

Fig 1. Time from first and last pregnancy to PH diagnosis and kidney failure in 29 women (A) and Kaplan-Meier plots of renal survival in PH1 patients who did not have kidney failure by the time of the 1st pregnancy (B).

Funding

  • Other NIH Support