Abstract: FR-PO230
Characteristics of Patients with Enteric Hyperoxaluria
Session Information
- Mineral Bone Disease: Transplant and Kidney Stones
October 25, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bone and Mineral Metabolism
- 502 Bone and Mineral Metabolism: Clinical
Authors
- Laxamana, Trisha D., New York University, New York, New York, United States
- Modersitzki, Frank, New York University, New York, New York, United States
- Cazes, Miri, New York University, New York, New York, United States
- Sandorffy, Bronya L., New York University, New York, New York, United States
- Goldfarb, David S., New York University, New York, New York, United States
- Nazzal, Lama, New York University, New York, New York, United States
Background
Enteric hyperoxaluria (EH) is a condition characterized by oxalate (Ox) overabsorption in the digestive tract leading to increased renal excretion. It predisposes patients to recurrent kidney stones, nephrocalcinosis, & progressive kidney impairment w/ severe cases requiring renal replacement therapy. Management remains a challenge due to heterogeneity of underlying etiologies, lack of standard laboratory cut-offs for the development of its consequences, & individual treatment responses.
Methods
We conducted a retrospective cohort study of 40 patients enrolled in the EH Registry at NYU Langone Health w/ an aim to contribute to the understanding of EH. Through comprehensive chart review, the study explores demographic characteristics including age, gender (male (M) vs. female (F)), EH etiology, eGFR & interventions including calcium (Ca) supplement & potassium (K) citrate. A cross-section analysis of 24-hour urinary collections was conducted (Table 1).
Results
The cohort comprised 40 patients w/ EH (50% M, 50% F) w/ a mean age of 59 (58 M, 61 F). Etiologies were Crohn's disease (40%), Roux-en-Y gastric bypass (12.5%), pancreatic insufficiency (25%), and short bowel syndrome (22.5%). Patients had eGFR >60 ml/min (70%), 45-59 (10%), 30-44 (10%), 15-29 (5%), <15 (2.5%), & unknown (2.5%). For intervention, 32.5% were on K citrate, 57.5% w/ history of K citrate use, and 22.5% were on Ca supplements. Urine collections showed significant risk for recurrent CaOx stones w/ high Ox & CaOx supersaturation (SS).
Conclusion
This cohort includes patients w/ mild to moderate CKD. Crohn's disease was the most common etiology. Significant gender differences were observed in urinary profiles in EH patients, w/ M showing higher Ox & SS CaOx despite higher volumes & citrate. Supplementation w/ citrate & Ca are used by a significant portion of this cohort but did not alleviate significant risk of stone recurrence or progressive CKD.
Table 1. 24-hour Urinary Profile
| M (n=20) (mean/SD) | F (n=20) (mean/SD) | |
| Volume (L/d)* | 2.46(0.96) | 1.75(0.92) |
| SS CaOx (L/d) | 13.67(76.70) | 12.51(42.95) |
| Ox (mg/d) | 74.96(64.62) | 59.26(36.64) |
| Ca (mg/d)* | 137.08(118.28) | 80.90(58.06) |
| Citrate (mg/d)* | 426.74(274.99) | 288.84(284.23) |
| pH | 6.38(5.55) | 6.21(0.78) |
| Sodium (mmol/d) | 187.29(70.88) | 125.10(74.02) |
*p<0.01