Q87.41

Clinical Causes: Genetic mutations in the FBN1 gene, which encodes the protein fibrillin-1, are the primary cause of Marfan syndrome. Inherited autosomal dominant pattern, meaning a single copy of the altered gene can cause the disorder. In some cases, the mutation occurs spontaneously with no family history. The abnormality in connective tissue affects the elasticity and strength of blood vessel walls, heart structures, and other tissues.

Key Symptoms: Tall stature with disproportionately long arms, legs, fingers, and toes. Chest deformities such as pectus excavatum (sunken chest) or pectus carinatum (pigeon chest). Joint hypermobility, leading to flexible joints that move beyond normal ranges. Eye problems including dislocated lenses, myopia, or early-onset glaucoma. Aortic dilation or aneurysm, which can weaken the vessel wall and increase risk of tear or rupture. Mitral valve prolapse, leading to heart murmurs or symptoms of mitral regurgitation. Stretch marks on the skin that are not related to weight gain or pregnancy. Difficulty with physical activities due to cardiovascular or musculoskeletal complications.

Diagnosis Path: Diagnosis involves a combination of clinical evaluation and genetic testing. Healthcare providers typically perform detailed physical examinations to assess physical features, such as height, limb proportions, and joint flexibility. Echocardiography is essential to evaluate the heart and blood vessels, especially the aorta. Genetic testing for FBN1 mutations can confirm the diagnosis, particularly in uncertain cases. Additional tests may include eye examinations and imaging studies to assess associated conditions. Family history plays a significant role, and screening relatives can help identify affected individuals early.

Treatment Protocols: Regular monitoring of cardiovascular health with echocardiograms to track aortic size and valve function. Medications such as beta-blockers or angiotensin receptor blockers to slow the progression of aortic dilation. Surgical intervention may be necessary to repair or replace the aortic valve or ascending aorta if dilation reaches critical levels. Management of skeletal and eye symptoms through orthopedic and ophthalmologic care. Lifestyle modifications to avoid strenuous activities that may elevate blood pressure or stress the cardiovascular system. Genetic counseling for affected individuals and their families to understand inheritance and implications.