Lenz–Majewski hyperostotic dwarfism

Lenz–Majewski Hyperostotic Dwarfism

Lenz–Majewski hyperostotic dwarfism is a rare genetic disorder characterized by skeletal dysplasia, intellectual disability, and distinctive craniofacial features. It is named after the researchers W. Lenz and F. Majewski, who first described the condition.

Clinical Features

Patients with Lenz–Majewski hyperostotic dwarfism typically present with:

• Skeletal abnormalities: These include generalized hyperostosis, which is an excessive growth of bone, leading to thickened bones. Affected individuals often have short stature due to disproportionate growth of the long bones.
• Craniofacial dysmorphism: Common features include a prominent forehead, hypertelorism (wide-set eyes), and a broad nasal bridge.
• Intellectual disability: Most individuals with this condition have some degree of intellectual disability, although the severity can vary.
• Dental anomalies: These may include delayed eruption of teeth and malocclusion.
• Skin and soft tissue abnormalities: Some patients may have thickened skin and soft tissue overgrowth.

Genetics

Lenz–Majewski hyperostotic dwarfism is caused by mutations in the PTDSS1 gene, which encodes an enzyme involved in phospholipid biosynthesis. The condition is inherited in an autosomal dominant manner, meaning a single copy of the mutated gene is sufficient to cause the disorder.

Diagnosis

Diagnosis is typically based on clinical evaluation, radiographic findings, and genetic testing to identify mutations in the PTDSS1 gene. Radiographs often reveal thickened calvaria, hyperostosis of the long bones, and other characteristic skeletal changes.

Management

There is no cure for Lenz–Majewski hyperostotic dwarfism, and treatment is primarily supportive. Management may include:

• Orthopedic interventions: To address skeletal deformities and improve mobility.
• Educational support: Tailored educational programs to support learning and development.
• Regular monitoring: To manage and monitor potential complications such as dental issues and skin abnormalities.

Prognosis

The prognosis for individuals with Lenz–Majewski hyperostotic dwarfism varies depending on the severity of symptoms and associated complications. With appropriate management, individuals can lead fulfilling lives, although they may require ongoing medical and educational support.

Also see

• Skeletal dysplasia
• Intellectual disability
• Craniofacial dysmorphism
• Autosomal dominant disorders