Neonatal Marfan syndrome (nMFS) is a rare and severe form of Marfan syndrome, with distinct characteristics at birth. This condition is a genetic disorder affecting connective tissue, which provides strength and flexibility to various body structures. Unlike classic Marfan syndrome, nMFS manifests with rapid progression of symptoms during infancy.
Signs and Physical Characteristics
Infants with neonatal Marfan syndrome display physical features from birth, impacting multiple body systems. Musculoskeletal signs include severe joint contractures, particularly affecting the elbows and hips (arthrogryposis), which limits movement. Loose and redundant skin may contribute to a somewhat “aged” facial appearance, and the ears can have a crumpled look.
Skeletal characteristics also include a long, slender body shape (dolichostenomelia). The chest may show deformities such as a sunken appearance (pectus excavatum) or a protruding chest (pectus carinatum). Ocular abnormalities, such as lens dislocation, where the eye’s natural lens shifts out of place.
The Genetic Basis of the Condition
Neonatal Marfan syndrome arises from mutations within the FBN1 gene. This gene provides instructions for producing fibrillin-1, a protein important for connective tissue. The mutations linked to nMFS often occur within exons 23 to 32 of the FBN1 gene.
These specific mutations lead to a more severe disruption of fibrillin-1 function compared to those found in classic Marfan syndrome. In most instances, nMFS results from a de novo mutation (meaning it occurred spontaneously and was not inherited).
The Diagnostic Process
Confirming a diagnosis of neonatal Marfan syndrome begins with a physical examination, where doctors identify the characteristic signs present at birth. Observing features such as severe joint contractures, loose skin, and a distinctive facial appearance can prompt further investigation. These initial observations guide the subsequent diagnostic steps.
A crucial diagnostic tool is an echocardiogram, an ultrasound of the heart, evaluates its structure and function. This test assesses for issues like severe mitral and tricuspid valve prolapse, where heart valves do not close properly, and enlargement of the aortic root. An ophthalmologic examination is also performed to check for lens dislocation or other eye abnormalities. A definitive diagnosis is established through genetic testing, which precisely identifies the specific FBN1 gene mutation responsible for the condition.
Medical Management and Treatment
Managing neonatal Marfan syndrome requires a multidisciplinary team of medical specialists. This team includes:
- Cardiologist for heart issues
- Orthopedist for skeletal concerns
- Pulmonologist for lung complications
- Ophthalmologist for eye care
The goal of treatment is to manage symptoms and improve the infant’s quality of life.
Cardiac issues are a primary focus. Medications help manage heart function and blood pressure. In some cases, cardiovascular surgery may be necessary to address severe valve leakage or aortic root dilation. For skeletal challenges, physical and occupational therapy improve joint mobility and address contractures. Respiratory support may also be needed due to weak lung tissue and breathing difficulties.
Prognosis and Life Expectancy
Neonatal Marfan syndrome carries a serious prognosis due to severe, rapidly progressive cardiovascular complications. These include significant heart valve dysfunction and progressive heart failure, which can be difficult to manage. Most infants do not survive past the first two years of life.
Ongoing research and aggressive medical management continuously work to address these severe complications. Medical advancements aim to improve outcomes and provide the best possible care for these infants.