HSCT for Sickle Cell Not Linked to Increased Chronic Kidney Disease Prevalence

Findings from a new study demonstrated that hematopoietic stem cell transplantation (HSCT) for patients with sickle cell disease was not associated with a significant increase in chronic kidney disease.

A team led by Emily Limerick, MD, The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins Medicine, evaluated the prevalence of chronic kidney disease prior to and following operation as well as the incidence of acute kidney injury within days of HSCT.

“Though HSCT can reverse the SCD phenotype, acute and chronic kidney dysfunction may be an unintended consequence,” the team wrote. “The incidence of acute kidney injury (AKI) and the effect of different HSCT regimens on progression or amelioration of CKD in adults with SCD have not previously been reported.”

Thus, the cohort study analyzed prospectively collected data from 106 patients with sickle cell disease who had undergone HSCT at the National Institutes of Health (NIH) Clinical Center.

More than half (n = 71) of the patients had an HLA-matched sibling. A smaller proportion had haploidentical HSCT (N=26) where nonmyeloablative conditioning was given, and fewer underwent gene therapy (N=9) where a myeloablative regimen was employed.

All patients’ renal function were assessed at baseline and annually for 3 years.

Acute kidney injury was defined and evaluated according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria.

At baseline, the prevalence of chronic kidney disease 6% (eGFR <60 ml/min/1.73m²) — this prevalence did not change significantly post-HSCT.

However, the investigators noted that when defined less conservatively (urine albumin to creatinine ratio (UACR) ≥30 mg/g; or eGFR <60 ml/min/1.73m²), chronic disease prevalence at baseline was 48%, followed by 62% at year 1 (P = .02), 55% at year 2 (P = .26), and 55% at year 3 (P = .54).

“The incidence of CKD any time after HSCT was 1% and 11% according to each of these CKD definitions, respectively,” the investigators wrote.

Furthermore, they reported that baseline median eGFR was 139.7 ml/min/1.73m² and declined by 7.6, 11.6, and 20.9 ml/min/1.73m2 each year post-HSCT (P < 0.0001).

Hyperfiltration (eGFR ≥150 ml/min/1.73m²) was present in 34% of patients at baseline; however, that steadily declined to 12% after 3 years following operation. (P = .0006).

Overall, patients with normal eGFR (60-149 ml/min/1.73m²) increased from 60% at baseline to 80% at 3 years post-HSCT.

There was no noted association of worsening eGFR with gender, engraftment status, transplant regimen, or conditioning agent (each variable, P > .005).

And finally, 58% of patients experienced acute kidney injury in the 1st 100 days following transplantation. Over that subset, 77% were mild, 13% were moderate, and 10% were severe. The investigators considered these findings to be consistent with previous data.

Thus, Limerick and colleagues underscored the preservation of renal function following hematopoietic stem cell transplantation.

The study, “Renal Function Is Preserved after Hematopoietic Stem Cell Transplantation for Sickle Cell Disease,” was published online by Blood.