Moyamoya Syndrome in Children With Sickle Cell Disease in Saudi Arabia: A Single-Center Experience

Background Sickle cell disease (SCD) is relatively common in Saudi Arabia. Its neurologic complications such as stroke and Moyamoya syndrome (MMS) can be severe and devastating. Such complications can be minimized by modern investigative tools such as transcranial Doppler (TCD) ultrasound, which is unavailable in many high-risk places. Our aim is to investigate the prevalence and characteristics of these complications in children with SCD in our center where TCD is not available. Methods We conducted a retrospective record review of children with SCD admitted to the pediatric ward and visited the pediatric hematology outpatient clinic of King Fahad Military Medical Complex, Dhahran, Saudi Arabia, from January 2010 to December 2021. The target population was children aged six months to 14 years with SCD and a history of stroke or transient ischemic attacks (TIAs). Their magnetic resonance imaging/magnetic resonance angiography (MRI/MRA) of the brain radiographic features were reviewed. A descriptive analysis was used to summarize the demographic characteristics and clinical features of patients with and without MMS. Results Twenty-six children (out of 385 with sickle cell anemia, originating mainly from the southwestern and eastern provinces of Saudi Arabia) experienced an overt stroke with an overall prevalence of 6.7%. All patients with stroke were originally from the Southwestern province. Their genotype was SS, and the median age at the onset of the first stroke was six years (IQR: 5.5). The main presenting symptoms were seizures (57.7%), motor weakness (42.3%), headache (15.3%), cranial nerve palsies (11.5%), cognitive deficit (7.6%), and dysphasia (3.8%). The majority of strokes were ischemic (92.3%). MMS was detected in 61.5% and was seen at the onset of the first stroke in all patients with this MRA abnormality. Seven children with moyamoya (43.8%) had recurrent strokes. Conclusion In this study, the prevalence of overt stroke is 9% in children with SCD originating from the southwestern region of Saudi Arabia (26/286), and 61.5% of them (16/26) had MMS. It is absent in the children of Eastern origin (99 children). In places lacking TCD facilities, further studies are required to determine if MRA brain screenings of children with SCD may detect MMS before the onset of stroke and help start protective therapy.