Moyamoya disease in Italian monozygotic twins

Moyamoya angiopathy - Is there a Western phenotype?

Moyamoya disease (MMD) is a chronic cerebrovascular disease involving progressive bilateral stenosis of the intracranial segments of the internal carotid arteries. It results in the development of a rich, but friable collateral supply, prone to rupture. The disease is well described in Japanese literature and was originally thought to be a predozminantly Eastern disease. However, the recent literature describes a Western phenotype that may present with a different clinical course. This review aims to describe the variations in the epidemiology of the MMD between Eastern and Western populations, the possible reasons for them and highlight their implications for clinical practise and future research.

Single Nucleotide Polymorphism in Patients with Moyamoya Disease

Moyamoya disease (MMD) is a chronic, progressive, cerebrovascular occlusive disorder that displays various clinical features and results in cerebral infarct or hemorrhagic stroke. Specific genes associated with the disease have not yet been identified, making identification of at-risk patients difficult before clinical manifestation. Familial MMD is not uncommon, with as many as 15% of MMD patients having a family history of the disease, suggesting a genetic etiology. Studies of single nucleotide polymorphisms (SNPs) in MMD have mostly focused on mechanical stress on vessels, endothelium, and the relationship to atherosclerosis. In this review, we discuss SNPs studies targeting the genetic etiology of MMD. Genetic analyses in familial MMD and genome-wide association studies represent promising strategies for elucidating the pathophysiology of this condition. This review also discusses future research directions, not only to offer new insights into the origin of MMD, but also to enhance our understanding of the genetic aspects of MMD. There have been several SNP studies of MMD. Current SNP studies suggest a genetic contribution to MMD, but further reliable and replicable data are needed. A large cohort or family-based design would be important. Modern SNP studies of MMD depend on novel genetic, experimental, and database methods that will hopefully hasten the arrival of a consensus conclusion.

The roles of methylenetetrahydrofolate reductase 677C>T and 1298A>C polymorphisms in moyamoya disease patients

PURPOSE

The methylenetetrahydrofolate reductase (MTHFR) 677C>T and 1298A>C polymorphisms, which are associated with hyperhomocysteinemia and nitric oxide (NO) deficiency (which is related to atherothrombosis and cerebral ischemia), have not been studied in moyamoya disease. A case-control study was performed to investigate whether the MTHFR 677C>T and 1298A>C polymorphisms contribute to moyamoya disease (MMD).

METHODS

One hundred and seven Korean patients with MMD (mean age, 20.85 ± 15.89 years; 66.4 % female) and 232 healthy control subjects (mean age, 23.99 ± 16.16 years; 56.8 % female) were included. Genotyping for the MTHFR 677C>T and 1298A>C polymorphisms and measurements of homocysteine, folate, vitamin B12, and NO in the cerebrospinal fluid (CSF) were performed. The statistical analysis was performed by multivariate linear regression and logistic regression.

RESULT

The MTHFR 677CT+TT genotype frequency was significantly increased with early-onset MMD (<10 years) compared with late-onset MMD (≥10 years) (adjusted odds ratio, 3.392; 95 % confidence interval, 1.294-8.893, P = 0.013). The MTHFR 677C-1298C/677T-1298A diplotype (1.71 ± 1.23 arbitrary units) presented significantly lower NO levels in the CSF compared with the 677C-1298A/677C-1298A diplotype (11.40 ± 12.24 arbitrary units).

CONCLUSION

The MTHFR 677C>T and 1298A>C polymorphisms have restricted roles in the Korean MMD population. Therefore, further studies involving larger and more heterogeneous cohorts are needed to extend our understanding of the influence of polymorphisms in MTHFR and other thrombophilic genes on MMD.

Surgical outcomes and predictors of stroke in a North American white and African American moyamoya population

BACKGROUND

The majority of moyamoya surgical series have been confined to Asian and pediatric populations. Few have studied demographics, risk factors, and outcomes in adult North American populations.

OBJECTIVE

To examine outcomes after revascularization for moyamoya in white and African American adults and to assess for predictors of recurrent stroke.

METHODS

A retrospective review of 75 non-Asian patients undergoing 110 procedures at the Mayo Clinic was performed. Demographics, known moyamoya associations, cerebrovascular risk factors, and autoimmune diseases were recorded. Primary outcomes for vascular events were assessed with Kaplan-Meier analysis. Fisher exact methods were used to evaluate for associations with recurrent events.

RESULTS

Mean age was 42 years, and mean follow-up was 47 months. Seventy-one of the 75 patients were white. The majority had bilateral disease (n = 49). Perioperative ischemic events occurred in 5 patients (4.5%). The 5- and 10-year event rates were 5.8% and 9.9%. Significant associations were found with a history of thyroid disease (P = .05) and recurrent stroke. A trend was also found between hypertension and autoimmune disease with recurrent stroke.

CONCLUSION

Outcomes were favorable with revascularization in this subset with moyamoya. A significant association between a history of thyroid disease and recurrent stroke was found. Additionally, high prevalences of autoimmune disease, hypertension, and thyroid disease were found in our cohort, suggesting that they may play a role in the pathophysiology and progression of moyamoya disease in this population. A new classification for moyamoya is proposed based on these data.

Caucasian familial moyamoya syndrome with rare multisystemic malformations

Moyamoya disease is an idiopathic progressive steno-occlusive disorder of the intracranial arteries located at the base of the brain. It is associated with the development of compensatory extensive network of fine collaterals. Moyamoya disease is considered syndromic when certain genetic or acquired disorders such as polycystic kidney disease, neurofibromatosis, or meningitis are also present. Although the genetic contribution in moyamoya is indisputable, its cause and pathogenesis remain under discussion. Herein, we report a rare occurrence of moyamoya syndrome in two European Caucasian siblings in association with unusual multisystemic malformations (polycystic kidney disease in one, and intestinal duplication cyst in the other). The karyotype was normal. No mutation in the RFN213 gene was found, and none of the HLA types linked to moyamoya disease or described in similar familial cases were identified. By describing these multisystemic associations, polycystic kidney disease for the second time, and intestinal malformation for the first time in the literature, our report expands the phenotypic variability of moyamoya syndrome. The coexistence of disparate malformations among close relatives suggests an underlying common genetic background predisposing to structural or physiological abnormalities in different tissues and organs.

Presentation and treatment of monozygotic twins with congenital central hypoventilation syndrome

Congenital central hypoventilation syndrome is a rare genetic disorder characterized by hypoventilation during sleep secondary to a blunted response to hypercapnia and hypoxia. The current case report describes developmentally normal four-year-old monozygotic twin boys who presented in infancy with variable presentations and clinical severity of congenital central hypoventilation syndrome. Both were managed with noninvasive positive pressure ventilation.

Analysis of human leucocyte antigen genes in Caucasian patients with idiopathic moyamoya angiopathy

BACKGROUND

The etiology and genetic susceptibility of Moyamoya angiopathy (MMA) (Moyamoya disease, Moyamoya syndrome and unilateral type of MMA) still remain unclear. In Asian patient cohorts several HLA markers were described to be associated with MMA, but in Caucasians very little is known about genetic susceptibility of this angiopathy.

METHOD

We analysed DNA of 33 Caucasian patients with MMA for HLA-A, HLA-B, HLA-DRB1, and HLA-DQB1 markers, respectively. HLA frequencies of all 33 patients with MMA were compared with HLA-frequencies of Caucasian controls. Additionally, subgroup analysis of 22 patients with Moyamoya disease (MMD) and 11 patients with unilateral type of MMA was performed.

FINDINGS

Significant association was observed for HLA-DRB1*03 and HLA-DRB1*13 in all 33 patients (P (c) < 0.001 and P (c) < 0.001, respectively). Moreover, HLA-A*02 (P (c) = 0.009); HLA-B*08 (P (c) = 0.009), and HLA-DQB1*03 (P (c) = 0.003) frequencies were higher in all patients with MMA when compared with the controls. In addition, in 22 patients with MMD a higher frequency of HLA-DRB1*03 (P (c) < 0.001) was observed when compared with controls.

CONCLUSIONS

The results of this study indicate a putative association of HLA markers with MMA in Caucasian patients. Further studies are needed to elucidate the role of human MHC in the pathogenesis of this angiopathy.

Caution in Treating Transsphenoidal Encephalocele with Concomitant Moyamoya Disease

A basal encephalocele is a rare congenital malformation involving a cranial bone defect and cystic-like herniation through the defect. Moyamoya is a rare cerebrovascular disease of unclear etiology involving occlusion of the distal internal carotids and formation of collateral vascular networks. Both diseases have been correlated with optic disc anomalies, hypopituitarism, and midfacial defects. We present a case of a 2-year-old boy with a midline facial cleft who underwent surgical correction of a basal encephalocele. His moyamoya disease may have contributed to a vascular complication. There is growing evidence indicating an overlap in disease profiles for these two rare diseases. In addition, molecular evidence indicates elevated levels of fibroblast growth factor and transforming growth factor in both diseases, suggesting common molecular pathways.

Familial occurrence of moyamoya disease: a clinical study

BACKGROUND

We reviewed a consecutive series of moyamoya disease (MMD) in children and studied their familial pedigrees to determine whether they showed specific clinical features or patterns of inheritance, and to investigate any correlation between familial MMD and common Asian diseases.

METHODS

Cases of familial MMD (N=10) were reviewed in the aspect of clinical presentation, such as, symptoms and signs, age of onset, imaging studies including magnetic resonance imaging (MRI), cerebral angiography, and single photon emission computed tomography (SPECT), and operative results including complications, to identify differences between these patients and those with sporadic MMD (N=194). The male to female ratio in those with familial MMD was 4:6 and mean age was 8 years (3-17). All were ischemic cases and five showed cerebral infarction on MRI. As a preliminary genetic study, familial pedigrees were examined. In addition, their familial histories concerning common Asian diseases, such as, hepatic disease, cancers, stroke, coronary heart disease, amyloidosis, and systemic lupus erythematosus, were investigated by telephone survey.

RESULTS AND CONCLUSIONS

The familial MMD cases did not reveal any differences from the other MMD children in terms of clinical findings, imaging data, or surgical results. In our series, five cases (50%) showed MMD between siblings. Familial MMD relations were also observed with cousins, a mother, and an aunt. No specific pattern of genetic inheritance was observed, and no relation was found between the familial occurrence of MMD and common Asian diseases.

Similar TIAs and corresponding alterations in regional cerebral perfusion in Caucasian monozygotic twins with moyamoya disease

We previously reported the first Caucasian monozygotic twins with moyamoya disease (MMD). In both patients, hyperventilation induced similar transient onset of left arm and hand paresthesias. Cerebral single photon emission computerized tomography (SPECT) showed overlapping perfusion abnormalities in the left parietal areas. Similarly, EEG showed high amplitude, bilateral, anterior, slow wave activity in the delta range during hyperventilation and rebuild-up phenomenon in both twins. Similar clinical symptoms mirrored alterations in regional cerebral perfusion by SPECT and EEG in our Caucasian monozygotic twins with MMD.

Familial moyamoya disease in Caucasians

There are few reports of moyamoya disease (MMD) in the Caucasian population and even fewer descriptions of the natural history of the disease. The study reports a 12-year follow-up of two white male siblings with MMD. Although both brothers had a persistently abnormal electroencephalogram and a learning disorder, the siblings recovered on aspirin and antiepileptic therapy with minimal neurologic residua. The occurrence of MMD in these siblings contributes to the evidence that MMD has a hereditary basis in Caucasians, as well as the Japanese. Even with the use of conservative measures, children may still have persistent yet minor cerebrovascular insults. In addition to the two patients discussed, this study reviewed the literature on all cases of MMD reported within families. Future follow-up studies are required to determine the natural history and the appropriate medical and surgical management of MMD.