Can psoriasis present with nail pitting as the only symptom?

Nail Pitting as the Sole Manifestation of Psoriasis

Yes, psoriasis can present with nail pitting as the only symptom, occurring in approximately 6% of psoriasis cases where nail involvement is the sole manifestation of the disease. 1

Clinical Presentation of Isolated Nail Psoriasis

Nail psoriasis can affect both fingernails and toenails, with the following characteristic features:

Matrix Involvement

• Pitting (small depressions in the nail plate)
• Leukonychia (white spots)
• Red spots in lunula
• Nail plate crumbling

Nail Bed Involvement

• Onycholysis (separation of nail from nail bed)
• Oil-drop discoloration (salmon patches)
• Subungual hyperkeratosis
• Splinter hemorrhages

Epidemiology and Association with Other Forms of Psoriasis

• Nail involvement occurs in approximately 50% of all psoriasis patients 2, 3
• Up to 90% of patients with psoriatic arthritis have nail changes 2, 3
• Isolated nail psoriasis without skin lesions occurs in 6% of cases 1

Diagnostic Considerations

When evaluating a patient with isolated nail pitting, consider the following:

1. Examine all nails carefully - While pitting may be the most obvious sign, look for subtle signs of other nail psoriasis manifestations
2. Check for minimal skin lesions - Examine typical psoriasis predilection sites (scalp, elbows, knees, intergluteal cleft)
3. Assess for joint symptoms - Morning stiffness, joint pain, or swelling may indicate early psoriatic arthritis
4. Consider dermoscopy (onychoscopy) - Can detect early psoriatic nail changes before they become clinically apparent 3

Differential Diagnosis

Nail pitting can occur in other conditions:

• Alopecia areata
• Eczema
• Secondary fungal infections
• Lichen planus
• Traumatic nail changes

Clinical Implications

Isolated nail psoriasis has important implications:

1. Disease progression indicator - Nail psoriasis correlates with more severe disease, earlier onset, and higher risk of psoriatic arthritis 1
2. Quality of life impact - Can cause significant functional impairment and reduced quality of life 1
3. Diagnostic challenge - May be overlooked or misdiagnosed when it's the only manifestation 4

Treatment Considerations

Treatment should be based on severity and impact:

• Mild isolated nail pitting: Topical therapies (corticosteroids, calcipotriol)
• Moderate to severe nail involvement: Consider intralesional injections
• Multiple nails or significant impact: Systemic therapies may be warranted, especially if early signs of psoriatic arthritis develop

Key Pitfalls to Avoid

1. Overlooking isolated nail psoriasis - Remember that nail changes may precede skin or joint manifestations by years
2. Misdiagnosing as fungal infection - Consider obtaining samples for mycology to rule out concurrent fungal infection
3. Underestimating impact - Nail psoriasis can significantly affect quality of life even without skin lesions
4. Delayed treatment - Early intervention may prevent progression to more severe nail dystrophy

In conclusion, nail pitting can indeed be the sole manifestation of psoriasis, and recognizing this presentation is important for early diagnosis and management of the disease.