Transcranial Doppler sonography and the effect of haematopoietic stem cell transplantation in sickle cell disease

Sylvia Thurn; Katharina Kleinschmidt; Irena Kovacic; Christina Wendl; Ralf A Linker; Selim Corbacioglu; Felix Schlachetzki

doi:10.1186/s42466-022-00175-y

Transcranial Doppler sonography and the effect of haematopoietic stem cell transplantation in sickle cell disease

Neurol Res Pract. 2022 Apr 4;4(1):12. doi: 10.1186/s42466-022-00175-y.

Authors

Sylvia Thurn¹, Katharina Kleinschmidt², Irena Kovacic^{3

4}, Christina Wendl⁵, Ralf A Linker^{3

4}, Selim Corbacioglu², Felix Schlachetzki^{6

7}

Affiliations

¹ Institute of Diagnostic Radiology, University Medical Center Regensburg, Regensburg, Germany.
² Department of Paediatric Haematology, Oncology and Stem Cell Transplantation, University Medical Center Regensburg, Regensburg, Germany.
³ Department of Neurology, University of Regensburg, Bezirksklinikum Regensburg, Regensburg, Germany.
⁴ Department of Neurology, University Medical Center Regensburg, Regensburg, Germany.
⁵ Center for Neuroradiology, Bezirksklinikum Regensburg and University Medical Center Regensburg, Regensburg, Germany.
⁶ Department of Neurology, University of Regensburg, Bezirksklinikum Regensburg, Regensburg, Germany. felix.schlachetzki@klinik.uni-regensburg.de.
⁷ Department of Neurology, University Medical Center Regensburg, Regensburg, Germany. felix.schlachetzki@klinik.uni-regensburg.de.

Abstract

Background: Sickle cell disease (SCD) is one of the most prevalent monogenetic diseases worldwide and one of the most serious complications is stroke. Transcranial Doppler (TCD) demonstrated to be highly predictive for an imminent stroke by measuring blood flow velocities in the basal cerebral arteries. Currently, the only curative therapy for SCD is hematopoietic stem cell transplantation (HSCT). The aim of this study is to verify the correlation between blood flow velocities and stroke including the effect of HSCT.

Methods: In our retrospective single-center study a total of 26 sickle cell patients (HbSS, HbSß⁺-thalassemia, HbSSα-thalassemia minima, HbSSα-thalassemia minor and HbSC) were analyzed between 2010 and 2016. The highest time averaged maximum mean blood flow velocity (TAMMV) measured was documented and evaluated with respect to SCD genotype and effect of HSCT. Acute and symptomatic as well as silent strokes were recorded as separate parameters.

Results: In our study, ten patients had normal blood flow velocities before HSCT (six HbSS and four HbSß⁺-thalassemia patients) and 13 patients presented with abnormal TCD (eight HbSS, three HbSSα-thalassemia minima, one HbSSα-thalassemia minor and one HbSC). Thirteen of 26 study participants (ten HbSS and three HbSß⁺-thalassemia patients) received HSCT. In two patients, TAMMV in basal cerebral arteries remained "normal", in one they remained conditional and in one TAMMV was reduced to normal. Four of 26 study participants (15.4%), including all patients with HbSS genotype, presented with a stroke, but none had "abnormal" TAMMV with TCD performed after the onset of stroke in each case. At the time we performed the TCD, the patients had already suffered the stroke.

Conclusion: In our study, none of the patients with stroke displayed abnormal blood flow velocities in TCD. Yet, HSCT at this stage of the disease still had a positive effect on TAMMV. Further studies are needed whether this effect converts into reduced stroke risk at all or only selected SCD patients undergoing HSCT.

Keywords: Haematopoietic stem cell transplantation; Sickle cell disease; Stroke; Transcranial Doppler.