Subtotal versus total splenectomy in children with sickle cell disease: Clinical outcomes and splenic function assessed by pocked red blood cell count

Abstract Background: The spleen is one of the first organs affected by sickle cell disease (SCD). While splenectomy may be indicated in some patients to prevent life-threatening recurrent acute splenic sequestration (ASS), the choice between subtotal and total splenectomy remains controversial due to concerns regarding preservation of splenic function and postoperative complications. Objectives: To compare clinical outcomes and splenic function assessed by pocked red blood cell (RBC) count in children with SCD after total or subtotal splenectomy, a surgical procedure in which only the upper splenic pole is preserved. Methods: We conducted a single-center, retrospective study in 68 children with SCD who underwent splenectomy between 2010 and 2022 in a French university hospital reference center (GR-Ex/CPP-DC2016-2618/CNIL-MR01). Clinical outcomes were assessed within two years following splenectomy. Pocked RBC counts were measured in a subgroup of 54 splenectomized patients using differential interference contrast (DIC) microscopy and imaging flow cytometry (IFC). Results: Compared with the total splenectomy group (n=30), patients in the subtotal splenectomy group (n=38) were younger (median [IQR]: 4.6 [3.9–5.7] vs. 5.8 [4.6–9] years, p=0.01) and had a higher preoperative incidence of ASS (mean ± SD: 0.7 ± 0.6 vs. 0.4 ± 0.5 episodes per year, p=0.02). Early postoperative morbidity was higher in the subtotal splenectomy group, with longer intensive care unit stays (3 [1.5–3] vs. 1 [1–1] days, p=0.04), more frequent fever (47 vs. 7%, p<0.001), and prolonged morphine use (3 [2–4] vs. 1 [1–1] days, p=0.01). During the first postoperative year, the subtotal splenectomy group experienced more vaso-occlusive crises (1.6 ± 1.5 vs. 0.8 ± 1.2 episodes per year, p=0.02) and acute chest syndromes (0.6 ± 0.8 vs. 0.1 ± 0.4 episodes per year, p=0.01). However, by the second year, the incidence of these events was similar between the two groups. The incidence of infectious complications did not differ and no recurrence of ASS occurred in either group, with residual spleen size, assessed by annual ultrasound, remaining stable. Analysis of pocked RBC counts showed significantly lower values in the subtotal splenectomy group (n=32) at 2.8 [1.8–4.6] years after splenectomy, compared with the total splenectomy group (n=22), when measured by DIC (39 [30–46] vs. 44 [41–49] %, p=0.02) or IFC (30 [25–34] vs. 37 [30–43] %, p=0.02), consistent with partial preservation of splenic function. Longitudinal measurements in a subset of 11 patients who underwent subtotal splenectomy demonstrated stable pocked RBC counts over a two-year follow-up period. Conclusion:Compared with total splenectomy, subtotal splenectomy in children with SCD is associated with an increased incidence of early inflammatory and vaso-occlusive events, but it appears to allow partial and possibly long-lasting preservation of splenic function, which may be particularly beneficial for this population. These findings support individualized surgical decision-making, balancing the benefits of preserving splenic function with the risk of early postoperative complications. Pocked RBC quantification appears to be a promising tool for assessing splenic function in patients with SCD.