Session: 112. Thalassemia and Globin Gene Regulation: Poster I
Hematology Disease Topics & Pathways:
Research, Clinical Research, Thalassemia, Hemoglobinopathies, Pediatric, Diseases, Real-world evidence, Study Population, Human
We designed a single-center retrospective cohort study to explore the correlation between nmGFR and eGFR equations based on creatinine, cystatin C, or both. Patients with TDT aged 0-17 years who had a nmDTPA study and serum cystatin C between 2013-2023 were included. Cystatin C measurements taken on the same day or up to 7 days from their DTPA scan were used. Eight eGFR calculations were performed (Schwartz, Schwartz-Lyon, Cr CKID U25, Filler, CysC Zapatelli, CysC CKID U25, Cr-CysC Zapatelli, Cr-CysC CKID U25). The Pearson correlation (rho) was used to measure the correlation of each eGFR equation versus the nmGFR. Mean bias (95% confidence intervals, CI) was calculated using the Bland-Altman method assuming constant variance.
Eleven children (55% female) with TDT (73% β0/β0 or β0/β+, 9% E0/β0, 18% non-deletional alpha thalassemia) with median age of 13 years were included. Nine (82%) children were receiving deferasirox for iron chelation, one (9%) was receiving deferoxamine and one (9%) was being phlebotomized having undergone a hematopoietic stem cell transplant. Two (18%) children were concurrently receiving hydroxyurea.
The mean nmGFR was 94.1+/-20.9 mL/min/1.73 m2, 72.3% had a normal nmGFR > 90 mL/min/1.73 m2. The Cr-CysC CKID U25 equation showed the strongest correlation to nmGFR (rho=0.84, p=0.002) with the lowest risk of bias (-3.01, 95% CI -28.5-25.1). The Cr CKID U25 and CysC CKID U25 equations showed moderate correlations [(rho=0.61, p=0.045) and (rho=0.64, p=0.047)] but showed significant bias [(-21.8, 95% CI -58.1–14.6) and (19.2, 95% CI -10.3 – 48.7)]. The Schwartz, Schwartz-Lyon, Filler, CysC Zapatelli, Cr-CysC Zapatelli equations did not correlate well with the nmGFR.
Most commonly used eGFR calculations poorly estimate renal function in children with transfusion-dependent thalassemia. The Cr-CysC CKID U25 equation showed strong correlation with the nmGFR and may represent a better biomarker for renal dysfunction in this population. A large prospective cohort study is needed to confirm and validate these findings.
Disclosures: Zavitz: Chiesi: Other: Travel support . Geerlinks: Pfizer: Consultancy. Tole: Novo Nordisk: Consultancy; Sanofi: Consultancy; Octapharma: Consultancy, Other: travel support; Roche: Consultancy.
See more of: Oral and Poster Abstracts