Beau's Lines: Causes and Treatment Options
Beau's lines are transverse depressions in the nail plate caused by temporary arrest of nail matrix function, and treatment should focus on addressing the underlying cause while supporting nail regrowth.
Causes of Beau's Lines
Beau's lines develop when nail matrix proliferation is temporarily inhibited. The width of the lines correlates with the duration of the insult to the nail matrix 1. Common causes include:
Systemic Factors
- Severe systemic illnesses 2
- Major medical illnesses causing inflammation of the matrix or digital blood vessels 1
- Severe infections 1
- Fever 1
- Metabolic disturbances
- Chemotherapy agents (inhibit mitotic activity in nail matrix) 1
Local Factors
- Trauma to the fingertip or nail 3
- Fractures and immobilization of the affected extremity 4
- Cutaneous vasculitis (possibly through circulating immune complexes affecting nail bed microvasculature) 1
- Local inflammation
- Exposure to cold temperatures in patients with Raynaud's disease 2
Other Factors
- Medications
- Viral infections (e.g., Coxsackie virus may directly damage the nail matrix) 1
- Autoimmune diseases 5
Clinical Presentation and Diagnosis
- Transverse, band-like depressions extending from one lateral edge of the nail to the other 1
- May affect all nails at corresponding levels (systemic causes) or be limited to one or few nails (local causes) 1
- Fingernails are more frequently affected than toenails 1
- The lines move forward with nail growth and eventually grow out
- Onychomadesis (complete nail shedding) represents an extreme form of Beau's lines 1
Treatment Approach
1. Identify and Treat the Underlying Cause
- For systemic illness: Treat the primary condition
- For trauma-related cases: Allow time for healing and protect from further injury
- For medication-induced cases: Consider medication adjustment if possible
2. Supportive Nail Care
- Apply white soft paraffin ointment to the affected nails every 2-4 hours to promote recovery and reduce discomfort 6
- Avoid further trauma to affected nails
- Keep nails trimmed short to prevent catching and further damage
- Avoid harsh chemicals and irritants that may worsen nail damage
3. Monitoring and Follow-up
- Monitor nail growth - Beau's lines typically advance with the linear growth of the nails and eventually disappear 1, 3
- Complete recovery of the nail plate surface may take 4-6 months, depending on the severity 1
- No specific treatment is usually required beyond addressing the underlying cause, as the nail changes are generally self-limiting 1
4. Prevention of Recurrence
- Address any identified risk factors
- Maintain good overall health
- Protect nails from trauma
- Proper management of any underlying systemic conditions
Special Considerations
- If Beau's lines appear without an obvious cause, consider screening for underlying systemic conditions 2
- The presence of Beau's lines on all nails suggests a systemic cause, while isolated lines may indicate local trauma 1, 3
- In cases of onychomadesis (complete nail shedding), patience is required as regrowth may take several months 1
Prognosis
The prognosis for Beau's lines is generally excellent. Once the underlying cause is addressed, the affected nails typically grow out normally within 3-6 months, depending on the growth rate of the individual's nails 1, 3.