Workup for Vitiligo
In adults with vitiligo, check thyroid function tests as the primary laboratory workup, given the 34% prevalence of autoimmune thyroid disease in this population. 1
Clinical Diagnosis
The diagnosis of vitiligo is primarily clinical and straightforward in classical presentations:
- Classical symmetrical vitiligo can be confidently diagnosed in primary care without extensive testing 1
- Atypical presentations require referral to dermatology for expert assessment 1
Key Clinical Assessment Components
Document the following at initial evaluation:
- Skin type classification (Fitzpatrick I-VI) - this guides treatment selection 1
- Pattern of depigmentation (symmetrical vs. segmental)
- Disease extent and distribution using serial photographs 1
- Family history - autoimmune disease present in 32% of first-degree relatives 1
- Personal history of other autoimmune conditions 1
Diagnostic Tools
Wood's lamp examination is useful for:
- Identifying depigmented areas not visible to the naked eye, especially in pale skin (types I-II) 1
- Assessing disease extent and activity
- Monitoring treatment response 1
The Wood's lamp shows actively depigmenting areas appearing larger under UV than visible light, while repigmenting areas may appear larger or smaller 1.
Laboratory Workup
Recommended Testing
Thyroid function screening should be performed in all adults with vitiligo:
- TSH and thyroid antibodies (anti-thyroid peroxidase, anti-thyroglobulin)
- Evidence: 34% of adults with vitiligo have autoimmune thyroid disease 1
- Grade D recommendation, Level 3 evidence 1
Additional Considerations
While not explicitly mandated by guidelines, consider screening for:
- Other autoimmune conditions based on clinical suspicion
- Complete blood count if considering systemic therapies
- Vitamin D levels (given emerging evidence of supplementation benefits) 2
Psychological Assessment
Assess quality of life and psychological impact at the initial consultation 1:
- Vitiligo causes significant psychosocial burden including depression, anxiety, and social isolation 1
- Use standardized QoL assessment tools in clinical practice 1
- This assessment guides treatment intensity and need for psychological support 1
Common Pitfalls to Avoid
- Don't over-investigate classical presentations - extensive laboratory workups beyond thyroid function are not evidence-based for typical symmetrical vitiligo
- Don't skip thyroid screening - this is the single most important laboratory test given the high association with autoimmune thyroid disease
- Don't dismiss psychological impact - even limited disease can cause severe QoL impairment requiring intervention 1
- Don't confuse diagnosis with treatment planning - the workup is minimal; complexity lies in treatment selection, not diagnosis
Documentation
Establish baseline documentation with:
- Clinical photographs in natural and Wood's lamp lighting 1
- Disease extent mapping
- VASI (Vitiligo Area Scoring Index) or VETF scores if available for research/monitoring 1
The workup for vitiligo is intentionally streamlined because diagnosis is clinical in most cases, and the primary laboratory concern is screening for associated autoimmune thyroid disease.