Findings similar to our case were documented in case reports of 2 women (aged 34 and 42 years)1 presenting with asymptomatic, atrophic, well-demarcated, shiny, hypopigmented macules over the trunk and upper extremities, which demonstrated a thinned epidermis with coarse hyalinized collagen bundles in the mid and lower dermis. There was upper and diffuse dermal elastolysis (patient 1 and patient 2, respectively).1 Our patient’s lesions were hypopigmented and atrophic in appearance but were slightly scaly and also involved the extremities. Distinct from these patient reports, histopathology from our case demonstrated thin packed collagen bundles and decreased fragmented elastin filaments confined to the upper reticular and papillary dermis.
Plaque morphea is the most common type of localized scleroderma.2 The subtype APP demonstrates round to ovoid, gray-brown depressions with cliff-drop borders. They may appear flesh colored or hypopigmented.3,4 These sclerodermoid lesions lack the violaceous border classic to morphea. Sclerosis and induration also are typically absent.5 Clinically, our patient’s macules resembled this entity. Histopathologically, APP shows normal epithelium with an increased basal layer pigmentation; preserved adnexal structures; and mid to lower dermal collagen edema, clumping, and homogenization.3,4 Elastic fibers classically are unchanged, with exceptions.6-11 Changes in the collagen and elastin of our patient were unlike those reported in APP, which occur in the mid to lower dermis.
Guttate morphea demonstrates small, pale, minimally indurated, coin-shaped lesions on the trunk. Histopathology reveals less sclerosis and more edema, resembling LS&A.12 The earliest descriptions of this entity describe 3 stages: ivory/chalk white, scaly, and atrophic. Follicular plugging (absent in this patient) and fine scale can exist at any stage.13,14 Flattened rete ridges mark an otherwise preserved epidermis; hyalinized collagen typically is superficial and demonstrates less sclerosis yet increased edema.12-14 Fewer elastic fibers typically are present compared to normal skin. Changes seen in this entity are more superficial, as with our patient, than classic scleroderma. However, classic edema was not found in our patient’s biopsy specimen.
Superficial morphea, occurring predominantly in females, presents with hyperpigmented or hypopigmented patches having minimal to no induration. The lesions typically are asymptomatic. Histopathologically, collagen deposition and inflammation are confined to the superficial dermis without homogenization associated with LS&A, findings that were consistent with this patient’s biopsy.15,16 However, similar to other morpheaform variants, elastic fibers are unchanged.15 Verhoeff-van Gieson stain of the biopsy (Figure 3) showed the decreased and fragmented elastin network in the upper reticular and papillary dermis, making this entity less compatible.
Guttate LS&A may present with interfollicular, bluish white macules or papules coalescing into patches or plaques. Lesions evolve to reveal atrophic thin skin with follicular plugging. Histology demonstrates a thinned epidermis with orthohypokeratosis marked by flattened rete ridges. The dermis reveals short hyalinized collagen fibrils with a loss of elastic fibers in the papillary and upper reticular dermis, giving a homogenized appearance. Early disease is marked by an inflammatory infiltrate.17 Most of these findings are consistent with our patient’s pathology, which was confined to the upper dermis. Lacking, however, were characteristic findings of LS&A, including upper dermal homogenization, near-total effacement of rete ridges, orthokeratosis, and vacuolar degeneration at the dermoepidermal junction. As such, this entity is less compatible.
Atrophoderma elastolyticum discretum has clinical features of atrophoderma with elastolytic histopathologic findings.1 Anetoderma presents with outpouchings of atrophic skin with a surrounding ring of normal tissue. Histopathologically, this entity shows normal collagen with elastolysis; there also is a decrease in desmosine, an elastin cross-linker.1,3 Neither the clinical nor histopathologic findings in this patient matched these 2 entities.
The reported chronologic association of these lesions with an arthropod assault raised suspicion to their association with toxic insult or postinflammatory changes. One study reported mechanical trauma, including insect bites, as a possible inciting factor of morphea.11 These data, gathered from patient surveys, reported trauma associated to lesion development.1,17 A review of the literature regarding atrophoderma, morphea, and LS&A failed to identify pathogenic changes seen in this patient following initial trauma. Moreover, although it is difficult to prove causality in the formation of the original hypopigmented spots, the development of identical spots in a similar distribution without further trauma suggests against these etiologies to fully explain her lesions. Nonetheless, circumstance makes it difficult to prove whether the original arthropod insult spurred a smoldering reactive process that caused the newer lesions.
Hereditary connective-tissue disorders also were considered in the differential diagnosis. Because of the patient’s history of an unprovoked complete rotator cuff tear, Ehlers-Danlos syndrome was considered; however, the remainder of her examination was normal, making a syndromic systemic disorder a less likely etiology.Because of the distinct clinical and histopathologic findings, this case may represent a rare and previously unreported variant of morphea. Clinically, these hypopigmented macules and patches exist somewhere along the morphea-atrophoderma spectrum. Histopathologic findings do not conform to prior reports. The name atrophodermalike guttate morphea may be an appropriate appellation. It is possible this presentation represents a variant of what dermatologists have referred to as white spot disease.18 We hope that this case may bring others to discussion, allowing for the identification of a more precise entity and etiology so that patients may receive more directed therapy.