Dados do Trabalho
MULTIPLE DYSRAPHISMS IN FIVE PATIENTS AND MULTISITE CLOSURE OF THE NEURAL TUBE THEORY
Apresentação do caso
Multiple dysraphisms (MD) are defined as uncommon fetal malformations compared to isolated dysraphisms (ID) and approximately 4% of cases of neural tube formation defects. A new theory of multisite closure of the neural tube has been used to elucidate the pathophysiology of MD, since the theory of closure at a single site can make it difficult to understand the origin of this malformation. The objective is to present a series of MD cases, which are rarely reported in the literature.
There are 5 patients with the following diagnoses: 1) Male gender: three sites of dysraphism. Cutaneous aplasia associated with frontooccipital encephalocele, small cervical meningocele and sacral dermal sinus with cutaneous appendage. 2) Male gender: two dysraphisms. Cutaneous aplasia associated with frontal encephalocele and frontobasal (ethmoidal) encephalocele. 3) Female gender: two dysraphisms. Occipital encephalocele and thoracolumbar myelomeningocele. 4) Male gender: ambiguous genitalia, syndactyly: three dysraphic levels. Occipital meningocele, occult dysraphisms, cervical osseous (finding on X-ray) and occult thoracolumbar dysraphism (with twisted gluteal sulcus). 5) Male gender: two dysraphisms. Complex frontoparietal encephalocele and occult lumbosacral dysraphism (with twisted gluteal sulcus).
Two theories are accepted to explain neural tube closure. The unified theory of embryogenesis states that there is a progression of closure for the caudal and cranial neuropores from a common point. However, this explanation does not provide enough information to justify the formation of MD. Thus, a new theory proposes that closure by primary neurulation occurs at five different sites, while closure below the level of the second sacral vertebra occurs by secondary neurulation. The independence between the sites can produce different MD manifestations depending on the site where the blockade fails. Finally, it is possible to state that MD have a greater genetic involvement compared to ID, and therefore their genesis is controlled independently of folate supplementation.
Diagnosis of MD are rare compared to ID. The new multisite closure theory proposed to motivate this data, as well as to justify closure failures in regions whose unified theory of embryogenesis is not able to explain.
Referências (se houver)
Spinal Dysraphism; Embryology; Neural Tube
Fonte de Fomento (se houver)
Declaração de conflito de interesses de TODOS os autores
Não há conflito de interesse entre os autores
Malformações do sistema nervoso central
Felipe Oliveira Santos, Vinícius Carvalho Oliveira, Maria Eduarda Araújo Mendes Vieira, Igor Virgílio Carvalho Matias, Amanda Castro Oliveira, Barbara Cavalcante Barbosa , José Gilberto Brito Henriques