What causes vertical ridges and brittleness in all nails?

Vertical Ridges and Brittle Nails: Causes and Management

Direct Answer

Vertical ridges affecting all nails with increased brittleness are most commonly a normal consequence of aging, but require evaluation to exclude inflammatory conditions (lichen planus, psoriasis), nutritional deficiencies, or fungal infection. 1

Primary Causes

Age-Related Changes (Most Common)

• Vertical ridges running from cuticle to nail tip represent the most frequent etiology, occurring as the nail matrix's ability to produce smooth nails diminishes with age. 1
• Brittle nails are characterized by longitudinal ridging with splitting or brittleness of the nail plate, affecting up to 20% of the population, particularly women over 50 years. 2
• This is typically idiopathic when all nails are uniformly affected without other systemic symptoms. 3

Inflammatory Dermatologic Conditions

• Lichen planus produces thinning of the nail plate with subungual hyperkeratosis and longitudinal ridging. 1
• Psoriasis can cause nail thinning and longitudinal ridging affecting multiple nails. 1
• These conditions warrant examination for associated changes including pitting, onycholysis, subungual hyperkeratosis, or discoloration that distinguish inflammatory disease from simple aging. 1

Systemic and Nutritional Factors

• Nail brittleness may indicate systemic conditions, medication side effects, or nail matrix damage. 1
• Nutritional deficiencies (particularly biotin/vitamin B7), trace elements, and amino acids (especially cysteine) can contribute to brittle nails. 2, 4
• Environmental factors producing progressive dehydration of the nail plate play an important role in nail brittleness. 3

Diagnostic Approach

Key Clinical Features to Assess

• Examine for soft, friable texture suggesting fungal infection versus hard, brittle texture of non-infectious causes. 5
• Look for associated nail changes: pitting, onycholysis, subungual hyperkeratosis, or discoloration suggesting inflammatory disease. 1
• Assess for paronychia (nail fold swelling/erythema) which suggests Candida infection, particularly with occupational moisture exposure. 5

When to Suspect Fungal Infection

• Thickening, discoloration, and friable texture may indicate onychomycosis requiring mycological confirmation. 1
• However, approximately 50% of dystrophic nails are non-fungal despite similar clinical presentation, making laboratory confirmation essential before treatment. 6
• Obtain direct microscopy with potassium hydroxide preparation and fungal culture on Sabouraud's glucose agar if fungal infection suspected. 1

Critical Pitfall

• Do not assume fungal infection without laboratory confirmation—the nail surface in non-infectious conditions typically doesn't become soft and friable as in fungal infection. 5, 6

Management Algorithm

First-Line Conservative Management (All Cases)

1. Apply daily topical emollients to periungual folds, nail matrix, and nail plate to maintain hydration. 1
2. Use protective nail lacquers to limit water loss from the nail plate. 1
3. File nail surfaces gently with an emery board after softening in warm water. 1
4. Avoid trauma, nail biting, use of nails as tools, prolonged water soaking, and exposure to harsh chemicals. 1

Occupational Counseling

• Patients with chronic moisture exposure need guidance on protective measures: wear gloves (plastic over light cotton linings) while cleaning or working with chemicals. 1, 7
• This is particularly critical for those with wet occupations who develop chronic paronychia leading to proximal nail dystrophy. 1

Nutritional Supplementation (Idiopathic Cases)

• Oral biotin (vitamin B7) supplementation has been reported useful in improving nail strength for idiopathic brittle nail syndrome. 3, 2
• Consider trace elements and amino acids (especially cysteine) supplementation. 2

Treatment for Inflammatory Conditions

• For psoriasis or lichen planus affecting less than 3 nails: intralesional triamcinolone acetonide 5-10 mg/cc for nail matrix involvement. 1
• Topical steroids with or without vitamin D analogs for nail bed involvement. 1

Treatment for Confirmed Fungal Infection

• Treat confirmed fungal infections with systemic antifungal agents (terbinafine or itraconazole) only after mycological confirmation. 1
• Daily application of urea-based keratolytic cream to reduce nail thickness if needed. 1

Common Pitfalls to Avoid

• Neglecting occupational counseling in patients with chronic moisture exposure. 1
• Diagnosing fungal infection based on appearance alone without laboratory confirmation. 6
• Overlooking inflammatory dermatologic conditions that require specific anti-inflammatory treatment rather than antifungals. 1
• Failing to assess for systemic conditions or medication side effects that may be contributing. 1