Kidney Week

Abstract: SA-PO0176

Primary Hyperoxaluria Type 3 in Israel: A Nationwide Cohort Study

Session Information

• Tubular, Metabolic, and Systemic Noncystic Genetic Kidney Diseases
  October 24, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Genetic Diseases of the Kidneys

• 1202 Genetic Diseases of the Kidneys: Non-Cystic (Complex and Non-Cystic Monogenic)

Authors

• Benshalom, Efrat, Shaare Zedek Medical Center, Jerusalem, Jerusalem District, Israel

Efrat Benshalom, MD

• Shasha-Lavsky, Hadas, Galilee Medical Center, Nahariyya, Israel

Hadas Shasha-Lavsky, MD

• Levi, Shelly Shlomit, Schneider Children's Medical Center of Israel, Petah Tikva, Center District, Israel

Shelly Shlomit Levi

• Magen, Daniella, Rambam Health Care Campus, Haifa, Haifa District, Israel

Daniella Magen, MD

• Borovitz, Yael, Schneider Children's Medical Center of Israel, Petah Tikva, Center District, Israel

Yael Borovitz, MD

• Schreiber, Ruth, Soroka Medical Center, Be'er Sheva, South District, Israel

Ruth Schreiber, MD

• Frishberg, Yaacov, Shaare Zedek Medical Center, Jerusalem, Jerusalem District, Israel

Yaacov Frishberg, MD

Background

Primary hyperoxaluria type 3 (PH3), caused by pathogenic HOGA1 variants, is a rare disorder causing increased oxalate production. Data on natural history and long-term kidney outcomes are limited. We aimed to characterize the clinical outcomes of a national cohort of PH3 patients.

Methods

This retrospective study enrolled pediatric and adult PH3 patients from six medical centers in Israel. Data were collected from medical files. Kidney function was assessed using CKiD-U25 or CKD-EPI equations as appropriate. All centers received ethical approval for the study.

Results

Fifty-one patients were included, 26 males (51%) and 25 females (49%). Most were Ashkenazi Jewish (47%) or Druze (41%). Median follow-up was 8.3 years (IQR 2.8–15.2), with median age at last follow-up 15.5 years (IQR 8.5–19). Median age at first stone event was 2 years (IQR 0.8–4), and at diagnosis 3 years (IQR 1.5–9.3). Family history of nephrolithiasis was present in 55%.
78% experienced at least one stone event and 65% underwent urological intervention. Most events occurred early, with median age at last event 4.3 years (IQR 2.6–11). Five patients were symptomatic as adults; maximal age at event was 63 years. Recurrent stone disease affected 51%. Four patients had urinary tract infections, five had renal scarring, and none had nephrocalcinosis.
Kidney function remained preserved. Among 30 patients, mean eGFR was stable from diagnosis to last follow-up (103±22.5 vs. 96.7±17.3 ml/min/1.73m2, p=0.12). Hypertension and proteinuria were rare.
Only one patient progressed to kidney failure in the context of nephrotic syndrome without oxalate deposition on biopsy. eGFR decline was not associated with interventions, infections, or scarring.
Mean UOx levels declined non-significantly (2.2±2.1 to 1.47±0.85 ULN, p=0.12). Genotype analysis showed shared and ethnic-specific variants, without clinical differences between major groups.

Conclusion

This large nation-wide cohort describes long term outcome of PH3 patients. Despite early-onset, persistent hyperoxaluria, recurrent nephrolithiasis with substantial procedural burden, none developed nephrocalcinosis and kidney function remained preserved. No clear genotype-phenotype correlation was noted. Our findings support the relatively benign course of PH3 and highlight the need for early recognition and tailored management.