Abstract: SA-PO0537
Negative Creatinine and Cystatin C eGFR Discordance in HIV
Session Information
- CKD: Clinical - Therapies, CKM Health, Special Populations, and More
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: CKD (Non-Dialysis)
- 2202 CKD (Non-Dialysis): Clinical, Outcomes, and Trials
Authors
- Casas-Aparicio, Gustavo, Instituto Nacional de Enfermedades Respiratorias, Mexico City, CDMX, Mexico
- Leon Ortiz, Jose Antonio, Instituto Nacional de Enfermedades Respiratorias, Mexico City, CDMX, Mexico
- Sanchez Becerra, Regina, Instituto Nacional de Enfermedades Respiratorias, Mexico City, CDMX, Mexico
Background
Estimation of kidney function in people living with HIV (PLWH) has become increasingly complex due to widespread use of modern antiretroviral therapies that interfere with tubular creatinine secretion. Although these agents would be expected to lower creatinine-based estimated glomerular filtration rate (eGFR), marked discordance between creatinine (Cr)- and cystatin C (CysC)-based eGFR may occur, including a subgroup with lower CysC-based eGFR despite preserved Cr-based estimates. The significance of this negative discordance phenotype remains unclear. We aimed to characterize negative Cr–CysC eGFR discordance in PLWH.
Methods
We performed a retrospective observational study including PLWH receiving care at a tertiary referral center between 2018 and 2025. Adults with at least one paired Cr–CysC measurement were included. eGFR was calculated using CKD-EPI Cr- and CysC-based equations. Participants were classified as concordant (±30%), negative discordance (CysC-eGFR >30% lower than Cr-eGFR), or positive discordance (CysC-eGFR >30% higher than Cr-eGFR).
Because positive and negative discordance likely represent distinct phenotypes, primary analyses compared participants with negative discordance versus concordant eGFR estimates. Multivariable logistic regression identified factors independently associated with negative discordance.
Results
Among 359 PLWH included, negative discordance was observed in 15.6% (Figure 1). Correlation between Cr- and CysC-based eGFR was moderate (r=0.48), with greater dispersion across higher Cr-based eGFR ranges.
In multivariable analyses, current CD4 <200 cells/μL was independently associated with negative discordance (OR 3.98, p=0.046), whereas longer HIV duration was inversely associated with this phenotype (OR 0.93/year, p=0.040).
Conclusion
Negative Cr–CysC eGFR discordance is common among PLWH and is associated with active immunologic dysfunction. These findings suggest that immunologic factors may contribute to marked differences between Cr- and CysC-based kidney function estimates in this population.
Funding
- Government Support – Non-U.S.