Trichothiodystrophy without Associated Neuroectodermal Features in Two Siblings.

Area of Science:

• Genetics and Molecular Biology
• Dermatology
• Neuroscience

Background:

• Trichothiodystrophy (TTD) is a rare genetic disorder characterized by sulfur-deficient brittle hair.
• It often presents with a spectrum of neuroectodermal abnormalities, including photosensitivity, ichthyosis, intellectual impairment, and growth deficits.
• Phenotypic variability is a hallmark of TTD, ranging from mild hair defects to severe systemic involvement.

Observation:

• This case report focuses on two sisters diagnosed with TTD.
• Both sisters exhibited the cardinal sign of sulfur-deficient brittle hair.
• Notably, they presented with isolated hair fragility, lacking other typical neuroectodermal symptoms.

Findings:

• The clinical presentation of TTD can be highly variable, even within families.
• Isolated hair fragility, without other systemic features, is a possible manifestation of TTD.
• This underscores the importance of recognizing the full spectrum of TTD phenotypes.

Implications:

• Early and regular follow-up is crucial for patients with TTD, even those with seemingly isolated symptoms.
• Monitoring for potential neurological, physical, and sexual impairments is essential for timely intervention.
• This case broadens the understanding of TTD's phenotypic diversity and informs clinical diagnostic approaches.