Hair casts. Review and suggestion regarding nomenclature

Area of Science:

• Dermatology
• Trichology
• Pathology

Background:

• Hair casts are often misidentified as a single entity.
• Existing literature lacks clear differentiation between distinct hair cast types.
• This ambiguity hinders accurate diagnosis and understanding of associated conditions.

Purpose of the Study:

• To clearly distinguish and define two types of hair casts.
• To propose specific nomenclature for each type to prevent diagnostic confusion.
• To highlight the differing clinical associations and demographic profiles of each hair cast type.

Main Methods:

• Observational analysis of hair cast morphology and clinical data.
• Comparative study of features distinguishing the common and uncommon types.
• Review of existing literature and case reports.

Main Results:

• Identified a common type associated with parakeratotic scalp disorders, occurring in children and adults of both sexes.
• Identified an uncommon type, termed peripilar keratin casts, observed exclusively in females and typically unrelated to scalp diseases.
• Established distinct diagnostic features for each type.

Conclusions:

• Proposed nomenclature: 'parakeratotic hair casts' and 'peripilar keratin casts'.
• This differentiation aims to resolve confusion and improve clinical recognition of these distinct conditions.
• The proposed names reflect the etiology and morphology, aiding in accurate diagnosis and research.