Perforating lichen nitidus in the setting of atopic dermatitis.

Perforating lichen nitidus is a rare subtype of lichen nitidus, with approximately 11 cases reported worldwide. Lesions typically present in young male patients at sites prone to mechanical irritation, including the hands, feet, forearms, elbows, and knees. Classic histopathologic features of perforating lichen nitidus show a lymphohistiocytic infiltrate within the papillary dermis between hyperplastic rete ridges with transepidermal elimination of dermal contents. Very few cases are reported in the literature of lichen nitidus and its association with atopic dermatitis. This is the first case describing perforating lichen nitidus in a patient with a history of atopic dermatitis being treated with dupilumab injections. Lesions of perforating lichen nitidus worsened with successful treatment of atopic dermatitis. These findings suggest a unique pathophysiology of perforating lichen nitidus lesions.

A very rare localization of a rare disease: palmar lichen nitidus

Abstract Lichen nitidus is an uncommon lichenoid dermatosis that could be defined as multiple, separated, shiny, pinpoint, pale to skin-colored papules. Palmoplantar lichen nitidus is a quite rare variant of lichen nitidus. It is hard to make a diagnosis of palmar lichen nitidus when there are no lesions elsewhere on the body. There are some dermoscopic features defined for both palmoplantar and non-palmoplantar lichen nitidus that might be useful to facilitate the diagnosis before histopathological examination. Herein, we report a case of a 24-year-old man diagnosed with isolated palmar lichen nitidus with dermoscopic features and histopathological confirmation.

A very rare localization of a rare disease: palmar lichen nitidus.

Lichen nitidus is an uncommon lichenoid dermatosis that could be defined as multiple, separated, shiny, pinpoint, pale to skin-colored papules. Palmoplantar lichen nitidus is a quite rare variant of lichen nitidus. It is hard to make a diagnosis of palmar lichen nitidus when there are no lesions elsewhere on the body. There are some dermoscopic features defined for both palmoplantar and non-palmoplantar lichen nitidus that might be useful to facilitate the diagnosis before histopathological examination. Herein, we report a case of a 24-year-old man diagnosed with isolated palmar lichen nitidus with dermoscopic features and histopathological confirmation.

Facial hypopigmentation in skin of color: An atypical presentation of lichen nitidus.

Lichen nitidus is a benign skin condition of unknown etiology that is classically described on the trunk, extremities, and genitalia as pinpoint flat-topped papules. In dark-skinned persons, the lesions may appear shiny or even hypopigmented. Lichen nitidus is less often described on the face. We describe a series of pediatric patients with skin of color who presented with the chief complaint of facial skin lightening and had associated clinical findings consistent with lichen nitidus.

In vivo reflectance confocal microscopy for evaluating seborrheic keratosis, verruca plana, syringoma and lichen nitidus.

BACKGROUND: In clinical, common facial papule dermatosis such as seborrheic keratosis (SK), verruca plana (VP), syringoma and lichen nitidus (LN) is often misdiagnosed. Summarizing in vivo reflectance confocal microscopy (RCM) features of the facial papule dermatosis is helpful in the diagnosis of ambiguous lesions. The purpose of this study was to evaluate the features of SK, VP, syringoma, and LN in RCM. METHODS: We recruited 144 patients referred for unequivocal facial papule dermatosis including 60 patients with SK, 60 patients with VP, 10 patients with syringoma, and 14 patients with LN. The RCM images were evaluated at the epidermis, the dermoepidermal junction, and the dermis from both papule lesions and normal skin. RESULTS: In the epidermis, the cerebriform shape was the main RCM characteristic of SK and the "petal-like" structure was the main RCM characteristic of VP. In the dermoepidermal junction, the RCM features we found were as follows: For SK, the bright dermal papillary rings, the abnormal dermal papilla and the looped vessels were also observed at the abnormal dermal papilla. For VP, the bright dermal papillary rings and the point-like blood vessels were also observed at the round dermal papills. For LN, the round, enlarged, well-circumscribed dermal papillae and the enlarged dermal papillaes were heavily laden with individual highly refractive cells. In the dermis, RCM examination revealed brightly refractile teratogenous sweat tube, designing variably visible bright "moon" structures in all syringoma patients. CONCLUSION: Considering our results, RCM may be useful to non-invasively discriminate SK, VP, syringoma and LN in vivo.

An unusual variant of lichen nitidus: Generalized follicular spinous with perifollicular granulomas.

Several unusual variants of lichen nitidus are described in the literature. Spinous follicular lichen nitidus with perifollicular granulomas is one such variant characterized by generalized follicular as well as nonfollicular keratotic papules, which show perifollicular granulomas on histopathology as well as a lichenoid granulomatous tissue reaction typical of lichen nitidus. Owing to its atypical clinical and histopathologic manifestations, it raises several clinical possibilities and can be a diagnostic challenge. We report this rare variant of lichen nitidus in a 19-year-old female, and discuss its clinical and histopathological differential diagnosis.