Nonne-Milroy disease

=Nonne-Milroy Disease = Nonne-Milroy disease, also known as Milroy disease, is a rare genetic disorder characterized by congenital lymphedema. It primarily affects the lower limbs and is present from birth. This condition is named after the physicians who first described it, Dr. Nonne and Dr. Milroy.

Etiology

Nonne-Milroy disease is caused by mutations in the FLT4 gene, which encodes the vascular endothelial growth factor receptor-3 (VEGFR-3). This receptor is crucial for the normal development of the lymphatic system. Mutations in this gene lead to impaired lymphatic drainage, resulting in the accumulation of lymphatic fluid and subsequent lymphedema.

Clinical Features

The primary clinical feature of Nonne-Milroy disease is lymphedema of the lower extremities. This swelling is typically present at birth or develops shortly thereafter. Other features may include:

• Thickened skin over the affected areas
• Prominent veins
• Papillomatosis (small wart-like growths)
• Hydrocele in males

Diagnosis

Diagnosis of Nonne-Milroy disease is based on clinical evaluation, family history, and genetic testing. Lymphoscintigraphy may be used to assess lymphatic function. Genetic testing can confirm mutations in the FLT4 gene.

Differential Diagnosis

Nonne-Milroy disease should be differentiated from other causes of congenital lymphedema, such as:

• Turner syndrome
• Noonan syndrome
• Lymphedema-distichiasis syndrome

Management

There is no cure for Nonne-Milroy disease, but management focuses on alleviating symptoms and preventing complications. Treatment options include:

• Compression garments to reduce swelling
• Manual lymphatic drainage (MLD)
• Good skin care to prevent infections
• Surgical interventions in severe cases

Prognosis

The prognosis for individuals with Nonne-Milroy disease varies. While the condition is chronic, with appropriate management, individuals can lead relatively normal lives. However, they may be at increased risk for complications such as cellulitis.

Genetic Counseling

Nonne-Milroy disease is inherited in an autosomal dominant pattern. Genetic counseling is recommended for affected individuals and their families to discuss the risk of transmission to offspring and the implications of genetic testing.

Research and Future Directions

Ongoing research aims to better understand the molecular mechanisms underlying Nonne-Milroy disease and to develop targeted therapies. Advances in gene therapy and lymphatic biology hold promise for future treatment options.

See Also

• Lymphedema
• Genetic disorders
• Vascular anomalies

NIH genetic and rare disease info

• NIH info on Nonne-Milroy disease

Nonne-Milroy disease is a rare disease.