Blaschkolinear Acquired Inflammatory Skin Eruption (BLAISE): Case Report of a Young Man Whose Dermatosis had Features of Lichen Striatus and Blaschkitis

Abstract

Cutaneous conditions can follow Blaschko’s lines on the skin, which are thought to reflect patterns of cell migration and clonal expansion during embryonic development of the epidermis. These diseases are hypothesized to be caused by genetic mosaicism resulting from processes such as lyonization or somatic postzygotic mutation. Lichen striatus and blaschkitis are two such acquired inflammatory skin disorders that are distinguished in the literature by age of onset, location, and histopathological features. Lichen striatus is typically observed on the extremities of children and is characterized by lichenoid papules that appear in a linear distribution along Blaschko’s lines. Microscopic examination typically shows spongiosis, as well as lichenoid and periadnexal inflammation. Blaschkitis more commonly occurs in adults and frequently involves the truncal areas, including the chest and abdomen. Microscopic examination typically shows spongiotic dermatitis. We describe a young man with a linear eruption extending from the flexor aspect of his right wrist to his central chest, which has features of both lichen striatus and blaschkitis. Both lichen striatus and blaschkitis are self-limited diseases that may resolve within months. It has been suggested that lichen striatus and blaschkitis are not separate entities, but rather the two endpoints within the spectrum of blaschkolinear acquired inflammatory skin eruption (BLAISE). The overlapping features of lichen striatus and blaschkitis in our patient demonstrate the spectrum of clinical and pathologic features in patients with BLAISE.

An Unusual Rash in a Five-Year-Old Girl: Blaschkoid Distribution Is the Key to the Diagnosis

“…Dermal lymphocytic infiltrates surrounding the hair follicles and eccrine glands are also characteristic [ 7 ]. Focal spongiosis, exocytosis, necrotic keratinocytes, patchy hyperkeratosis, and dyskeratosis are changes noted in the epidermis [ 8 ].…”

An Unusual Case of Lichen Striatus Onset Under Dupilumab in a Patient With Alopecia Areata

“…Some authors retained that post zygotic somatic mutations of skin cells may determinate the genesis of a mosaicism, presenting different keratinocyte antigens. A mosaicism is that condition marked by the presence of more than one genetic line as a result of a DNA mutation, in a multicellular organism [2]. A blaskhoid eruption may appear, when this clone is target by a not specific immune system response, probably triggered by unknown factors 2 .…”

“…A mosaicism is that condition marked by the presence of more than one genetic line as a result of a DNA mutation, in a multicellular organism [2]. A blaskhoid eruption may appear, when this clone is target by a not specific immune system response, probably triggered by unknown factors 2 . Dupilumab is able to switch the immune response from a Th2 to a Th1 and Th17 pathway which, in our opinion, may induce autoimmune responses against mosaic cells and thus blaskhoid eruption in predispose patients [1].…”

Blaschko-linear manifestations in polygenic inflammatory disorders

“…23 such as the onset in adulthood, erythematous, pruritic skin papules and lichen striatus including distribution along the extremities and the presence of a bandlike inflammatory infiltrate, suggesting the diagnosis of Blaschko-linear acquired inflammatory skin eruption (BLAISE) was noted. 24 The histopathological diagnosis, acknowledged as the gold standard, was meticulously juxtaposed with clinical and dermoscopic diagnoses, with the outcomes presented in Table 2. The diagnosis of BLAISE requires histopathological analysis for confirmation.…”