Not every white spot is vitiligo

CASE DESCRIPTION

An 11-year-old female presented to our clinic with a dermatosis localized to her head, which had been previously diagnosed as vitiligo by two different physicians. The dermatosis was characterized by a paramedial band-like hypopigmented atrophic plaque that affected the forehead and scalp and extended from the interciliary region up to the vertex. On the forehead, the plaque had fine horizontal wrinkles, central vertical light brown macules and discrete hyperpigmented borders. The skin felt indurated and the subjacent bone was slightly sunken (Figure 1). The scalp presented with linear diffuse alopecia (scarring). There was another atrophic plaque affecting the right side of the forehead, above the eyebrow. It also had a band-like configuration but a bruise-like appearance (Figure 2). The lesion on the forehead was noticed approximately 15 months before assessment during the summer. It started as a small hypopigmented patch that progressively expanded until it became more evident. The plaque on the right side developed several months later after she got hit practicing wrestling. There were no accompanying symptoms. No other areas of the body were affected. Laboratory was unremarkable except for positive antinuclear antibodies. Skin biopsy showed slightly atrophic epidermis, dermal sclerosis, and mild superficial perivascular inflammatory infiltrate in the dermis. Brain MRI and consult to ophthalmology ruled out central nervous system (CNS) and eye involvement. The findings were consistent with a diagnosis of linear scleroderma en coup de sabre. The patient was referred to the department of Paediatric Rheumatology to start systemic treatment (Methotrexate 25 mg/week, folic acid 5 mg/week, Prednisone 10 mg OD).

Figure 1.

Band-like hypopigmented and atrophic plaque affecting forehead and scarring scalp (middle line).

Figure 2.

Band-like sclerotic plaque with bruise-like appearance (right side). Band-like hypopigmented and atrophic plaque affecting forehead and scarring scalp (middle line).

Discussion

Linear scleroderma en coup de sabre (ECDS) is a subtype of localized scleroderma (LS), an autoimmune condition that affects the connective tissue and which is characterized by sclerosis and fibrosis of the skin and subcutaneous tissue (Table 1). Its pathogenesis is not fully understood but damage of small vessels, activation of T-lymphocytes, and production of altered connective tissue are needed for the development of this condition. Other factors such as trauma, or genetic, immune, or infectious mechanisms may also be involved (1). LS is uncommon and affects mostly children (2,3). Its estimated incidence is 3.4 cases per million/year (≤16 years), but the true occurrence of this condition may be higher as it is often underrecognized or misdiagnosed (4) just as it happened in this particular case, that was initially misdiagnosed as vitiligo by two different physicians. Clinical presentation is characterized by a single linear plaque of indurated skin and a shiny ivory color with unilateral distribution affecting face and/or parietal region of the scalp which presents with alopecia. The lesions may extend to the cheek, nose and/or upper lip and subjacent tissues including muscles and bone, causing deformities or facial asymmetry (5). Extracutaneous affectation (CNS/ophthalmic) may also develop including epilepsy, neurologic deficit, uveitis, retinal detachment, or diplopia, among others. Therefore, a brain MRI and eye exam are mandatory in the assessment of these patients (6,7). ECDS is diagnosed based mainly on the characteristic cutaneous and soft tissue findings. Immunologic blood tests are not disease-specific or diagnostic for ECDS but may suggest autoimmune disease (8,9). Findings in skin biopsy are characterized by fibrosis and thickening of collagen fibres. In the inflammatory phase predominates a perivascular inflammatory infiltrate, while in the sclerotic phase this is reduced and appendages are atrophic or lost (10,11). The main differential diagnosis includes progressive hemifacial atrophy (PHA) or Parry–Romberg syndrome, a condition that is usually characterized by unilateral hemifacial atrophy that occurs progressively and slowly. There is still a great controversy if these two conditions are part of the same spectrum or different entities. Those who favour the latter, explain that patients with PHA do not present with skin sclerosis and the initial lesions appear in the cheek and nose area, affecting mostly the lower face unlike ECDS, the main feature of which is the skin atrophy that affects forehead and scalp. For those that consider that both conditions are linked, their argument is based in that the coexistence of ECDS and PHA may be present between 37% and 54% of cases (12). Other conditions that may need to be ruled out are traumatic injury, birthmarks, linear cutaneous lupus erythematosus, and linear facial lichen sclerosus (13). The main objective of ECDS therapy is to stop the disease activity and prevent disfigurement and or CNS/eye involvement (14). In general, immunosuppressive treatment is the most common treatment option. Paediatricians and family physicians must have a high index of suspicion in facial hypo/hyperpigmented band-like lesions with abnormal skin texture accompanied by scarring alopecia. An accurate and prompt diagnosis of ECDS would avoid severe facial deformities and CNS/eye sequelae (15).

Table 1.

Localized scleroderma classification

Types and subtypes	Clinical features
1. Generalized
	• ≥4 plaques • Superficial or deep • ≥2 more anatomic sites (confluent)
2. Circumscribed
a. Plaque morphea  b. Guttate  c. Atrophoderma of Pasini and Pierini  d. Keloid morphea  e. Lichen sclerosis et atrophicus*	• Affects dermis • May affects the subcutaneous tissue or superficial panniculus • Few plaques • Discrete • ≤2 anatomic areas affected • Most benign and common in general population
3. Linear morphea
a. Linear scleroderma  b. Morphea en coup de sabre  c. Progressive facial hemiatrophy	• Most common type in children • Fibrotic with Linear arrangement • May lead to contractures (limb deformities) • Affection scalp and middle line face (en coup the sabre) could be associated with CNS and eye involvement
4. Pansclerotic (deep) morphea
a. Morphea profunda  b. Subcutaneous morphea  c. Eosinophilic fasciitis	• Full thickness involvement • Affects face, scalp, trunk, and extremities (toes and fingertips are spare) • More disabling • Less common of all types
5. Mixed
	• Combination of two or more subtypes

*Its inclusion in this group is controversial. Some authors consider it as an independent disease.

Modified from ref. (8).

Informed Consent: Parent’s consent was obtained prior to taking pictures. No identifiers are included in the pictures.

Funding: There are no funders to report for this submission.

Potential Conflicts of Interest: All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.