Hypotrichosis with juvenile macular dystrophy

Hypotrichosis with Juvenile Macular Dystrophy (HJMD) is a rare genetic disorder characterized by the combination of hair loss (hypotrichosis) and a progressive degeneration of the macula, leading to a decrease in central vision (macular dystrophy). This condition is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene, one from each parent, to be affected.

Symptoms and Diagnosis

The primary symptoms of HJMD include sparse hair or hypotrichosis from birth or early childhood and progressive vision loss starting in childhood or adolescence due to juvenile macular dystrophy. The macular dystrophy associated with HJMD specifically affects the macula, the part of the retina responsible for sharp, detailed central vision. As the disease progresses, affected individuals may experience a significant decrease in visual acuity, potentially leading to legal blindness.

Diagnosis of HJMD is based on clinical examination, family history, and genetic testing. Ophthalmologic examinations can reveal characteristic changes in the macula, and genetic tests can identify mutations in the CDH3 gene, which has been linked to this condition.

Genetics

HJMD is caused by mutations in the CDH3 gene, which encodes P-cadherin, a protein that plays a crucial role in cell adhesion and signaling in the hair follicles and retina. The mutations lead to the malfunctioning of P-cadherin, disrupting the normal development and function of hair follicles and the retina, which manifests as hypotrichosis and macular dystrophy.

Treatment and Management

There is currently no cure for HJMD. Treatment focuses on managing symptoms and supporting the individual's quality of life. For the hair loss aspect, wigs and hairpieces may be used. For the vision loss, low vision aids and services are essential to help individuals maximize their remaining vision and maintain independence. Regular follow-ups with ophthalmologists and dermatologists are crucial for monitoring the progression of the disease and adjusting the management plan as needed.

Prognosis

The prognosis for individuals with HJMD varies. While the hair loss is typically non-progressive after adolescence, the vision loss due to macular dystrophy progressively worsens over time. Early intervention with low vision aids and services can significantly improve the quality of life for affected individuals.

NIH genetic and rare disease info

• NIH info on Hypotrichosis with juvenile macular dystrophy

Hypotrichosis with juvenile macular dystrophy is a rare disease.