Spleen Related Complications and Implications of Splenectomy in Patients with Hemoglobin SC Disease.
Authors: Subbannan Karthi , Ustun Celalettin , Natarajan Kavita , Clair Betsy , Kutlar Abdullah 
Published: April 2020

Abstract
The spleen is one of the earliest organs to undergo sickling-related damage with functional asplenia at a very early age followed by fibrosis and scarring with the absence of a palpable splenomegaly in patients with homozygous hemoglobin (Hb) SS. In contrast to Hb SS, 50% of Hb SC patients are reported to have persistent splenomegaly into adulthood. As a consequence, complications like splenic sequestration, infarction, and cytopenias are relatively common in adults with Hb SC. These symptoms might be severe enough to require splenectomy. Although there are several published reports on splenectomy in the pediatric population with Hb SC, little is known in adults in this regard. We therefore conducted a retrospective analysis of spleen related complications and splenectomy in adults with Hb SC. One hundred and twenty four adult Hb SC patients have been followed at the Sickle Cell Center, Medical College of Georgia. There were 60 males and 64 females. The median age was 27 (range 15–74 years old). Out of these 124 patients, 26 (21%) had palpable splenomegaly. Twelve (9.6%) patients underwent splenectomy. The reason for splenectomy was as follows: splenic infarction in 3/12 (25%), hypersplenism and sequestration in 5/12 (41.6%), subcapsular bleeding in 1/12 (8%), and information not available in 3/12 patients (25%). There was a significant difference between splenectomized and non-splenectomized patients in terms of Hb level (median 7.2 g/dL in the splenectomized vs. 12.5 g/dL in the non-splenectomized, p&lt;0.0001), platelet counts (median of 146 x 106/L vs. 275 x 106/L, p=0.031), palpable spleen (66% vs. 16%, p=0.00004), acute chest syndrome frequency (75% vs. 12%, p=0.0001), and cholecystectomy rate (66% vs. 13%, p=0.000006). None of these patients had a cholecystectomy at the same time as splenectomy. There was a trend towards higher incidence of stroke as well in these patients (8% vs. 0.8%, p=0.053). In addition, SC patients who underwent splenectomy were more likely to be on hydroxyurea therapy (4/12 vs. 6/112, p=0.001). Following splenectomy, the median Hb level increased from 7.2 g/dl to 11.4 g/dl (p=0.007) and the median platelet count increased from 146 x 106/L to 416 x 106/L (p=0.007). There was no difference in terms of Hb S, C, and F levels between the splenectomized and non-splenectomized groups. None of the patients in the splenectomized group had any significant morbidity or mortality from undergoing splenectomy. There seems to be a subgroup of patients with Hb SC who require splenectomy due to splenic complications who also have other organ related complications. Hb SC is generally considered to be a relatively mild form of sickle cell disease, especially in adults. However spleen related complications can occur and as evidenced by statistically significant rates of ACS, cholecystectomy, stroke, and more severe anemia and thrombocytopenia may represent a marker of a more severe phenotype. Splenectomy in these patients appears to be very effective and safe.