Dissection of the posterior inferior cerebellar artery in the hypereosinophilic syndrome

GWAS-based polygenic risk scoring for predicting cerebral artery dissection in the Chinese population

OBJECTIVE

Cerebral artery dissection (CeAD) is a rare but serious disease. Genetic risk assessment for CeAD is lacking in Chinese population. We performed genome-wide association study (GWAS) and computed polygenic risk score (PRS) to explore genetic susceptibility factors and prediction model of CeAD based on patients in Huashan Hospital.

METHODS

A total of 210 CeAD patients and 280 controls were enrolled from June 2017 to September 2022 in Department of Neurology, Huashan Hospital, Fudan University. We performed GWAS to identify genetic variants associated with CeAD in 140 CeAD patients and 210 control individuals according to a case and control 1:1.5 design rule in the training dataset, while the other 70 patients with CeAD and 70 controls were used as validation. Then Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) enrichment analyses were utilized to identify the significant pathways. We constructed a PRS by capturing all independent GWAS SNPs in the analysis and explored the predictivity of PRS, age, and sex for CeAD.

RESULTS

Through GWAS analysis of the 140 cases and 210 controls in the training dataset, we identified 13 leading SNPs associated with CeAD at a genome-wide significance level of P < 5 × 10- 8. Among them, 10 SNPs were annotated in or near (in the upstream and downstream regions of ± 500Kb) 10 functional genes. rs34508376 (OR2L13) played a suggestive role in CeAD pathophysiology which was in line with previous observations in aortic aneurysms. The other nine genes were first-time associations in CeAD cases. GO enrichment analyses showed that these 10 genes have known roles in 20 important GO terms clustered into two groups: (1) cellular biological processes (BP); (2) molecular function (MF). We used genome-wide association data to compute PRS including 32 independent SNPs and constructed predictive model for CeAD by using age, sex and PRS as predictors both in training and validation test. The area under curve (AUC) of PRS predictive model for CeAD reached 99% and 95% in the training test and validation test respectively, which were significantly larger than the age and sex models of 83% and 86%.

CONCLUSIONS

Our study showed that ten risk loci were associated with CeAD susceptibility, and annotated functional genes had roles in 20 important GO terms clustered into biological process and molecular function. The PRS derived from risk variants was associated with CeAD incidence after adjusting for age and sex both in training test and validation.

Case report: Serious unexpected vascular events in two patients with lymphocytic variant hypereosinophilic syndrome

Background

Lymphocytic-variant hypereosinophilic syndrome (L-HES) is a form of reactive hypereosinophilia, most commonly associated with interleukin-5 over-production by clonal, most commonly CD3-CD4+CD2hiCD5hiCD45RO+ T-cells. Patients often present with predominant cutaneous and soft-tissue manifestations, while cardiovascular involvement is uncommon.

Methods

We reviewed the medical files of two L-HES patients followed in our center who developed serious vascular complications and performed a literature review for similar cases.

Results

Patient 1, a 52-year-old female, presented with an ischemic stroke secondary to left middle cerebral artery dissection after 10 years of indolent L-HES. Blood eosinophilia was controlled with oral corticosteroids (OCS), but OCS-tapering attempts with hydroxyurea and pegylated interferon failed, prompting the introduction of mepolizumab with rapid normalization. Patient 2, a 62-year-old female, had been asymptomatic for 10 years without treatment when a NSTEMI occurred, due to coronary artery occlusion secondary to a large cauliflower-aneurysm of the proximal aorta and aneurysmal dilatation of several coronary arteries, requiring semi-urgent surgical management. Aortic wall staining for eosinophil major basic protein showed eosinophils in the adventitia. Blood eosinophilia was controlled with OCS.

Conclusions

Patients with apparently clinically benign L-HES may develop arterial complications, consisting in dissection and/or aneurysm dilatation of medium-to-large vessels with serious consequences. The value of performing regular vascular imaging and monitoring during follow-up has yet to be determined.

Literature reviews of stroke with hypereosinophilic syndrome

Hypereosinophilic syndrome (HES) is defined by persistently elevated blood eosinophil levels and is associated with evidence of organ damage. Cardiovascular involvement in HES is most commonly associated with Loffler endocarditis (cardiac HES). Cardiac HES is typically characterized by progressive subendocardial fibrosis with overlying mural thrombus formation, leading to restrictive dysfunction of the left ventricle. The thrombus from cardiac HES could result in cardiogenic stroke; however, most of the stroke cases with HES were not associated with huge thromboembolism rather multiple infarcts in the watershed area. The major clinical features of 97 previously reported cases of stroke with HES are as follows: the median age was 52 years, of which 61 (63%) were men; the initial presenting symptoms were neurological (73%), followed by headache (16%), respiratory symptoms (9%), and visual symptoms (9%). Almost half of the cases were diagnosed with cardiac HES. The characteristics of cardiac findings were mural thrombi, endomyocardial fibrosis, and a restrictive pattern of heart failure. Cerebral findings revealed 78 cases (80%) were described as multiple infarctions and 55 cases (57 %) were involved with watershed areas, whereas 11 cases (11％) were described as embolic stroke for one proximal large-vessel occlusion. Regarding treatment, 71 (73%), 28 (29%), and 16 (16%) patients were treated with steroids, anticoagulants, and antiplatelets, respectively. The overall mortality and recovery rates were 11% and 89%, respectively. Physicians should know most cases of stroke with HES are characterized by multiple infarctions in the watershed area, and cardiac HES is not always associated with stroke.