SICKLE CELL DISEASE | Hydroxyurea Use Linked To Higher Rates Of Spleen Removal

The study’s findings also indicated that SCD children treated with hydroxyurea underwent splenectomy surgery at a significantly younger age compared with those not given the oral medication.

That result came as a surprise to researchers, who expected contrary findings. “We hypothesized that as hydroxyurea gained widespread use, surgical splenectomy among pediatric patients with SCD occurred at a higher rate and older age among those taking hydroxyurea,” the team noted.

Treatment with hydroxyurea, a small molecule that increases the production of fetal haemoglobin — a form of haemoglobin that is more effective at transporting oxygen than its adult counterpart — was shown to decrease the frequency of VOCs and the need for blood transfusions in SCD patients. However, it is unclear whether hydroxyurea contributes to reduce spleen ischemia, and potentially increase the need for splenectomy, or spleen removal surgery.

The study, entitled “Pediatric Sickle Cell Disease Patients on Hydroxyurea Have Higher Rates of Surgical Splenectomy,” was conducted in the US where researchers analyzed data collected between 2005 and 2020 from 28,520 children with SCD identified in the Pediatric Health Information System (PHIS).

Approximately half of the patients were boys (51.5%), and 58.6% were non-Hispanic Black children. Nearly half had Medicaid insurance (45.6%) and 34.2% were treated with hydroxyurea. More than half of the children — 17,717 or about 62% — were diagnosed with sickle cell anaemia, the most common and often the most severe type of SCD.

Children treated with hydroxyurea had a significantly higher rate of splenectomy compared with those not treated with the medication (7.2% vs. 3.2%). The treated patients also were younger at the time they underwent surgery compared with those not on hydroxyurea (median age of 6.2 vs. 7.8). There were no differences in the length of hospital stay or the incidence of blood transfusion during surgery admission between the groups.

“Overall, this study highlights a novel observation that hydroxyurea therapy is associated with a higher rate of surgical splenectomy among patients with SCD, regardless of genotype [genetic background],” the researchers wrote.

This might be related to “the preservation of the spleen from auto-splenectomy, perhaps through fewer vaso-occlusive crises known to result in tissue loss,” the team noted. “In maintaining or even regaining functioning tissue, the spleen remains at risk for sequestration crisis or hypersplenism [overactive spleen], two common indications for a surgical splenectomy.”

“These findings provide useful information for clinicians and patients who benefit from this therapy,” the team wrote.

However, they also noted that further investigation is needed to clarify the reasons for surgical splenectomy at a younger age in children with sickle cell anaemia.

Source: Sickle Cell Anemia News