Impact of splenectomy on circulating microparticles in patients with sickle cell anemia.

INTRODUCTION: Circulating microparticles (MP) are being described as potential biomarkers for disease activity in a variety of conditions including sickle cell anemia (SCA). However, relatively little is known about the influence of spleen status on MP levels in patients with SCA. METHODS: Using a prospective study design we characterize circulating MP in 144 patients with SCA in steady state by assessing their cellular origin and their relationships to spleen status defined by clinical and imaging findings. In addition, MP levels were studied according to demographic characteristics, clinical status, treatment modalities, and other hematological and biochemical parameters. Absolute plasma concentrations of MP were determined by flow cytometry. RESULTS: Patients with SCA displayed a 10-fold increase in levels of MP derived from red blood cell (RBC) and platelets (PLT) when compared to their healthy counterparts (p < 0.0001). Splenectomized patients with SCA have more pronounced levels of MPRBC and MPPLT, and remained elevated after several weeks of follow-up. Levels of MP were not significantly associated with spleen removal procedures, age, gender, clinical severity score, hydroxyurea therapy, hemoglobin F, and co-existence of glucose-6-phosphate dehydrogenase deficiency. CONCLUSION: Collectively, these results suggest that splenectomy affects circulating levels of MP regardless of the known SCA modifiers and correlates.

Intracranial hemorrhage in primary immune thrombocytopenia (ITP): 20 years' experience in pediatrics.

Incidence of intracranial hemorrhage (ICH) among children with primary immune thrombocytopenia (ITP) varies among different studies. We published data during the period of 1997-2007 of ICH in children with primary ITP, addressing risk factors and outcome. The aim of this study is to assess changes in incidence, risk factors, and outcome of ICH in children with ITP from last decade and to report the overall 20 years' experience. We compared 2008-2018 with the decade before it. Data of children with ITP and ICH during study period and ITP control cases were analyzed. Neurosurgical intervention and outcome were also reported. A total of 4340 children with primary ITP were evaluated. Twenty-five (0.63%) ICH events were reported over 2 decades. Head trauma, hematuria, and platelet counts < 10 × 109/L were the risk factors mostly associated with ICH. Overall mortality was 24%, and a further 28% had neurologic sequelae. Neurosurgical intervention was done in 12% of cases with good outcome.Conclusion: Persistent platelet counts < 10 × 109/L were a significant risk factor for ICH in both time periods, while head trauma and hematuria were more reported in the period of 2008-2018 as significant risk factors for ICH. Outcome was comparable in both periods. What is Known: • ICH is a rare complication of ITP; however, early recognition of risk factors and aggressive treatment might lead to complete recovery without sequalae. Platelet counts less than < 10 × 109/L are the main risk factor for ICH. Few studies reported other significant risk factors. What is New: • Hematuria and head trauma are significant risk factors for ICH in ITP, in addition to having a persistently low platelet count < 10 × 109/L. (more than 90 days in chronic ITP, 45 days in persistent and 21 days in acute ITP) • Combined treatment with IVIG and HDMP followed by platelet transfusion was associated with complete recovery without sequelae in almost 50% of patients.