How we approach genetics in the diagnosis and management of vascular anomalies

Sturge-Weber syndrome: an update for the pediatrician

BACKGROUND

Sturge-Weber syndrome (SWS) is a rare congenital neurocutaneous disorder characterized by the simultaneous presence of both cutaneous and extracutaneous capillary malformations. SWS usually presents as a facial port-wine birthmark, with a varying presence of leptomeningeal capillary malformations and ocular vascular abnormalities. The latter may lead to significant neurological and ocular morbidity such as epilepsy and glaucoma. SWS is most often caused by a somatic mutation involving the G protein subunit alpha Q or G protein subunit alpha 11 gene causing various alterations in downstream signaling pathways. We specifically conducted a comprehensive review focusing on the current knowledge of clinical practices, the latest pathophysiological insights, and the potential novel therapeutic avenues they provide.

DATA SOURCES

A narrative, non-systematic review of the literature was conducted, combining expert opinion with a balanced review of the available literature. A search of PubMed, Google Scholar and Embase was conducted, using keywords "Sturge-Weber Syndrome" OR "SWS", "Capillary malformations", "G protein subunit alpha 11" OR "G protein subunit alpha Q".

RESULTS

One of the hallmark features of SWS is the presence of a port-wine birthmark at birth, and forehead involvement is most indicative for SWS. The most common ocular manifestations of SWS are glaucoma and choroidal hemangioma. Glaucoma presents in either in infancy (0-3 years of age) or later in life. Neurological complications are common in SWS, occurring in about 70%-80% of patients, with seizures being the most common one. SWS significantly impacts the quality of life for patients and their families, and requires a multidisciplinary approach for diagnosis and treatment. Currently, no disease-modifying therapies exist, and treatment is mostly focused on symptoms or complications as they arise.  CONCLUSIONS: SWS remains a complex and heterogeneous disorder. Further research is needed to optimize diagnostic and therapeutic strategies, and to translate insights from molecular pathogenesis to clinical practice.

Medical Management and Therapeutic Updates on Vascular Anomalies of the Head and Neck: Part 2

Discovery of inherited and somatic genetic mutations, along with advancements in clinical and scientific research, has improved understanding of vascular anomalies and changed the treatment paradigm. With aim of minimizing need for invasive procedures and improving disease outcomes, molecularly targeted medications and anti-angiogenesis agents have become important as both adjuncts to surgery, and increasingly, as the primary treatment of vascular anomalies. This article highlights the commonly used and emerging therapeutic medications for non-malignant vascular tumors and vascular malformations in addition to medical management of associated hematologic abnormalities.

Prevalence of aortic aneurysms and dissections in patients with systemic vessel aneurysms and dissections; matched case-control study using a national sample cohort

Objective

Aneurysms in systemic arteries are rare, and little is known about their relationship with aortic aneurysms. In this study, we aimed to evaluate the prevalence of aortic aneurysms and dissections (AAD) in patients with other systemic vessel aneurysms and dissections (OVAD) and identify their potential risk factors.

Methods

This cross-sectional study used a nationwide representative cohort sample from the Korea National Health Insurance Service-National Sample Cohort database. We defined OVAD as systemic vessel aneurysms and dissections excluding intracranial and aortic dissections and aneurysms. With a total of 690 OVAD patients and 2,760 non-OVAD matched controls, we investigated the prevalence of AAD in patients with OVAD and potential risk factors for their concurrence using the χ2 test and logistic regression.

Results

The prevalence of AAD in patients with OVAD was 10.6% (73/690) and 0.3% (9/2,760) in patients with non-OVAD. The adjusted odds ratio (OR) for having concurrent AAD with OVAD was 37.56 (95% CI: 18.29-77.12, p < 0.001) after stratification by sex, age, income, region of residence and after adjustment for hypertension, diabetes mellitus, dyslipidemia, and extent of disability. The adjusted ORs of AAD were significantly higher in females [adjusted OR = 47.63 (95% CI: 10.72-211.55)], and individuals aged ≥60 years [adjusted OR = 28.18 (95% CI: 13.42-59.17)], as well as those without hypertension [adjusted OR = 95.44 (95% CI: 18.21-500.23)], diabetes mellitus [adjusted OR = 46.39 (95% CI: 18.85-114.17)], without dyslipidemia [adjusted OR = 60.99 (95% CI: 20.83-178.56), p < 0.001 for all]. The prevalence of AAD significantly differed by according to specific sites of OVAD in carotid artery, upper extremity artery, iliac artery, lower extremity artery, and splanchnic artery (p < 0.001 for all).

Conclusions

The prevalence of AAD in patients with OVAD was 37.56 times higher than that in the matched population. We may approach aneurysms as systemic diseases and further investigations of pathophysiology would help to clarify the relationships between AAD and OVAD.

Sturge-Weber Syndrome: A Review of Pathophysiology, Genetics, Clinical Features, and Current Management Approache

Sturge-Weber syndrome (SWS) is a congenital, sporadic, and rare neurocutaneous disorder, characterized by the presence of a facial port-wine birthmark (PWB), glaucoma, and neurological manifestations including leptomeningeal angiomatosis and seizures. It is caused by a postzygotic, somatic, gain-of-function variant of the GNAQ gene, and more recently, the GNA11 gene in association with distinctive clinical features. Neuroimaging can help identify and stratify patients at risk for significant complications allowing closer follow-up; although no presymptomatic treatment has been demonstrated to be effective to date, these patients could benefit from early treatment and/or supportive interventions. Choroid plexus (CP) thickness measurements in brain magnetic resonance imaging (MRI) have a high sensitivity and specificity for early and incipient changes in SWS. In contrast, the absence of pathologic findings makes it possible to rule out associated neurological involvement and leads to periodical observation, with new imaging studies only in cases of new clinical signs/symptoms. Periodic ophthalmological examination is also recommended every 3 months during the first year and yearly afterwards to monitor for glaucoma and choroidal hemangiomas. Treatment for SWS depends on the extent and areas that are affected. These include laser surgery for PWB, anticonvulsants in the case of brain involvement, with either seizures or abnormal EEG, and medical treatment or surgery for glaucoma. Sirolimus has been used in a limited number of patients and appears to be a safe and potentially effective treatment for cutaneous and extra-cutaneous features, however controlled clinical studies have not been carried out. Better knowledge of GNAQ/GNA11 molecular pathways will help to develop future targeted treatments.

The Genetic Architecture of Vascular Anomalies: Current Data and Future Therapeutic Perspectives Correlated with Molecular Mechanisms

Vascular anomalies (VAs) are morphogenesis defects of the vascular system (arteries, capillaries, veins, lymphatic vessels) singularly or in complex combinations, sometimes with a severe impact on the quality of life. The progress made in recent years with the identification of the key molecular pathways (PI3K/AKT/mTOR and RAS/BRAF/MAPK/ERK) and the gene mutations that lead to the appearance of VAs has allowed the deciphering of their complex genetic architecture. Understanding these mechanisms is critical both for the correct definition of the phenotype and classification of VAs, as well as for the initiation of an optimal therapy and the development of new targeted therapies. The purpose of this review is to present in synthesis the current data related to the genetic factors involved in the etiology of VAs, as well as the possible directions for future research. We analyzed the data from the literature related to VAs, using databases (Google Scholar, PubMed, MEDLINE, OMIM, MedGen, Orphanet) and ClinicalTrials.gov. The obtained results revealed that the phenotypic variability of VAs is correlated with genetic heterogeneity. The identification of new genetic factors and the molecular mechanisms in which they intervene, will allow the development of modern therapies that act targeted as a personalized therapy. We emphasize the importance of the geneticist in the diagnosis and treatment of VAs, as part of a multidisciplinary team involved in the management of VAs.