Anonychia-onychodystrophy with brachydactyly type B and ectrodactyly

A rare genetic disorder affecting nail and limb development

Anonychia-onychodystrophy with brachydactyly type B and ectrodactyly is a rare genetic disorder characterized by abnormalities in the development of the nails and limbs. This condition is inherited in an autosomal dominant pattern, meaning a single copy of the altered gene in each cell is sufficient to cause the disorder.

Genetic Basis

The disorder is caused by mutations in specific genes that are crucial for the normal development of nails and limbs. These mutations disrupt the normal signaling pathways that guide the formation of these structures during embryonic development.

Autosomal dominant inheritance pattern

Clinical Features

Individuals with this condition typically present with:

• Anonychia: The absence of nails on the fingers and/or toes.
• Onychodystrophy: Malformation or dystrophy of the nails, which may appear thickened, discolored, or abnormally shaped.
• Brachydactyly type B: Shortening of the fingers and/or toes, particularly affecting the distal phalanges.
• Ectrodactyly: Also known as "split hand/foot malformation," this involves the absence of one or more central digits, resulting in a cleft appearance of the hand or foot.

Diagnosis

Diagnosis of anonychia-onychodystrophy with brachydactyly type B and ectrodactyly is primarily based on clinical evaluation and the characteristic physical findings. Genetic testing can confirm the diagnosis by identifying mutations in the associated genes.

Management

Management of this condition is symptomatic and supportive. It may involve:

• Orthopedic surgery to correct limb deformities and improve function.
• Occupational therapy to assist with daily activities and enhance hand function.
• Genetic counseling for affected individuals and their families to understand the inheritance pattern and implications for future offspring.

Prognosis

The prognosis for individuals with this condition varies depending on the severity of the limb and nail abnormalities. While the physical manifestations can be significant, they do not typically affect life expectancy.

Related pages

• Genetic disorder
• Brachydactyly
• Ectrodactyly
• Onychodystrophy