What is Nail Peeling (Onychoschizia)?
Nail peeling, medically termed onychoschizia or lamellar dystrophy, is a condition characterized by horizontal splitting and layering of the distal nail plate, most commonly affecting fingernails in adult women. 1, 2
Pathophysiology
The primary cause of onychoschizia is repeated cycles of hydration and dehydration of the nail plate. 2
- Experimental studies demonstrate that normal nails develop typical peeling changes after 21 days of repeated water exposure followed by dehydration 2
- Progressive wetting and drying causes individual nail cells to separate, creating empty spaces where layering becomes prominent 2
- This mechanical process results in the characteristic horizontal splitting at the distal free edge of the nail 1
Clinical Presentation
Onychoschizia manifests as lamellar splitting of the nail plate, typically affecting multiple fingernails simultaneously. 1, 3
- The average patient presents with approximately 7 affected fingernails 3
- The condition predominantly affects adult women 2
- Symptoms often persist for many years (average 11.6 years) if left untreated 3
- The splitting occurs horizontally in layers, distinguishing it from vertical nail splitting (onychorrhexis) 4
Key Differential Diagnoses
It is critical to distinguish onychoschizia from onycholysis (nail plate separation from the nail bed), which appears as whitish discoloration and has entirely different causes and treatments. 5, 6
- Onycholysis involves separation of the nail plate from the underlying nail bed, starting distally and progressing proximally, often associated with fungal infections, psoriasis, or drug reactions 4
- Onychomycosis presents with nail thickening, discoloration, and subungual hyperkeratosis, requiring antifungal treatment 4
- Behavioral disorders like onychophagia (nail biting) and onychotillomania (compulsive nail picking) are classified as obsessive-compulsive spectrum disorders and require different management 7
Contributing Factors
Environmental exposures are the primary risk factors for developing onychoschizia. 2
- Repeated water immersion (occupational or domestic) 2
- Exposure to organic solvents and detergents 2
- Manicuring practices and nail cosmetics 5
- Trauma from occupational activities 5
Clinical Significance
While onychoschizia does not directly impact mortality or major morbidity, it significantly affects quality of life through cosmetic concerns and social embarrassment. 7
- Patients experience similar psychosocial impact as those with other nail disorders 7
- The chronic nature of the condition (often lasting over a decade untreated) contributes to ongoing distress 3
- Proper diagnosis prevents unnecessary antifungal treatments prescribed when mistaken for fungal infections 7