Can depigmentation occur in scleroderma?

Depigmentation in Scleroderma

Yes, depigmentation absolutely occurs in scleroderma (systemic sclerosis), manifesting as vitiligo-like macules that can appear even in clinically uninvolved skin areas. This is a well-documented but often underrecognized cutaneous manifestation of the disease.

Clinical Presentation and Patterns

Depigmentation in scleroderma presents in two distinct patterns:

• Vitiligo-like macules are the primary depigmentation pattern, appearing as white patches that histologically and clinically resemble vitiligo but with subtle pathologic differences 1
• These depigmented areas can occur in skin that has never been clinically involved with skin thickening, indicating a systemic rather than purely local process 2
• Patients with diffuse cutaneous systemic sclerosis (dcSSc) are more likely to develop depigmentation in uninvolved skin compared to those with limited cutaneous disease 2

Pathophysiology and Mechanisms

The depigmentation in scleroderma involves immunologic mechanisms similar to vitiligo:

• Clinical, histologic, and electron microscopic studies demonstrate changes similar to vitiligo, with immunologic mechanisms involved in inducing the depigmentation 1
• Pigmented skin specimens show either higher epidermal melanin content or more severe pigmentary incontinence with increased dermal melanophages in the superficial dermis 2
• The changes are difficult to differentiate pathologically from unpigmented skin except for variations in melanin content and pigmentary incontinence 2

Mixed Pigmentary Changes

Scleroderma characteristically presents with both hyperpigmentation AND depigmentation:

• Increased pigmentation is actually more common than depigmentation in scleroderma, occurring even in areas never clinically involved with skin thickening 2
• Local factors including repetitive friction, trauma, or variations in skin temperature may influence the development, distribution, and severity of pigmentation abnormalities 3
• The coexistence of hyper- and depigmentation creates a distinctive "salt and pepper" appearance in some patients 3, 4

Clinical Significance and Diagnosis

Recognition of depigmentation patterns is important for several reasons:

• Depigmentation may be an early or presenting sign of systemic sclerosis sine scleroderma (without skin thickening), as documented in cases presenting with vitiligo-like depigmentation and interstitial pulmonary fibrosis 5
• Postinflammatory hypopigmentation or depigmentation may persist in skin of color despite regression of active disease, creating significant psychosocial impact 4
• These pigmentary changes have been recognized since the 19th century but their relationship to disease pathogenesis remains poorly understood 3, 1

Important Caveats

Key clinical pitfalls to avoid:

• Do not dismiss depigmented patches in a patient with suspected connective tissue disease as simple vitiligo without considering systemic sclerosis 1, 5
• Screen for underlying systemic sclerosis manifestations (Raynaud phenomenon, digital ulcers, interstitial lung disease, pulmonary arterial hypertension) when encountering unexplained depigmentation 6, 5
• In persons of color, the psychosocial impact of depigmentation is particularly significant and should not be overlooked 4
• There are currently no established evidence-based treatments for the depigmentation specifically, though treatment of the underlying scleroderma with immunosuppressives may be beneficial 6, 4