Laryngo-onycho-cutaneous syndrome

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Laryngo-onycho-cutaneous syndrome
Synonyms	Shabbir syndrome
Pronounce
Specialty	Medical genetics
Symptoms	Laryngeal abnormalities, nail dystrophy, skin lesions
Complications	N/A
Onset	Infancy
Duration	Lifelong
Types	N/A
Causes	Mutations in the LAMA3 gene
Risks
Diagnosis	Genetic testing, clinical evaluation
Differential diagnosis	Epidermolysis bullosa, Laryngeal papillomatosis
Prevention	Genetic counseling
Treatment	Supportive care, tracheostomy, surgical interventions
Medication
Prognosis	Variable, can be life-threatening
Frequency	Very rare
Deaths

Laryngo-onycho-cutaneous syndrome (LOC) is a rare genetic disorder that primarily affects the larynx, nails (onycho), and skin (cutaneous). This syndrome is characterized by severe skin abnormalities, nail malformations, and laryngeal defects. It is an autosomal recessive disorder, meaning that an individual must inherit two copies of the defective gene, one from each parent, to develop the syndrome.

Symptoms and Signs

The most common symptoms of LOC syndrome include skin abnormalities, nail dystrophy, and laryngeal stenosis. Skin abnormalities often present as thickened, scaly skin, particularly on the palms of the hands and soles of the feet. Nail dystrophy refers to malformations or deformities of the nails, which may be absent, rudimentary, or abnormally small in individuals with LOC syndrome. Laryngeal stenosis, or narrowing of the larynx, can lead to respiratory problems and a hoarse voice.

Causes

LOC syndrome is caused by mutations in the LAMA3 gene, which provides instructions for making a protein that is essential for the normal function of the skin, nails, and larynx. The LAMA3 gene is part of a larger family of genes known as the laminin genes, which play a crucial role in the structure and function of various tissues and organs in the body.

Diagnosis

Diagnosis of LOC syndrome is typically based on the presence of characteristic clinical features. Genetic testing can confirm the diagnosis by identifying mutations in the LAMA3 gene. Other diagnostic tests may include skin biopsy, laryngoscopy, and nail examination.

Treatment

There is currently no cure for LOC syndrome. Treatment is symptomatic and supportive, and may include skin care to manage the skin abnormalities, nail care for the nail dystrophy, and surgical intervention for laryngeal stenosis.

Prognosis

The prognosis for individuals with LOC syndrome varies depending on the severity of the symptoms. With appropriate management, many individuals with LOC syndrome can lead a normal life. However, severe laryngeal stenosis can be life-threatening if not properly managed.

See Also

• Genetic disorder
• Larynx
• LAMA3
• Laminin
• Autosomal recessive

NIH genetic and rare disease info

• NIH info on Laryngo-onycho-cutaneous syndrome

Laryngo-onycho-cutaneous syndrome is a rare disease.