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.

Generalized lichen nitidus in a 6-year-old girl with Down syndrome

Lichen nitidus is a generally asymptomatic disease identified by shiny, flesh-colored papules that are often limited to the trunk, upper limbs, and genitalia. Here, we describe a generalized presentation of lichen nitidus in a 6-year-old girl with Down syndrome. Lichen nitidus shares a known association with Down syndrome, and several case studies document patients with Down syndrome developing generalized lichen nitidus. The extensive nature of our patient's lichen nitidus, as well as the uncommon distribution, particularly on the face, adds to the currently limited primary literature on this subject.

Adnexotropic Variants of the Interface Dermatitides: A Review

The interface dermatitides encompass a vast array of cutaneous entities which, at times, may present with particular clinical variants with adnexal predilection. Similarly, hair follicle and eccrine gland involvement of some of these entities has been observed on histopathology. This review aims to describe the various adnexotropic presentations of the interface dermatitides. Recognizing that the adnexa can be a frequent site of involvement of these conditions may aid dermatopathologists in making the correct diagnosis and avoid misinterpreting adnexotropism for other conditions such as the great imitator, mycosis fungoides.

Simultaneous Occurrence of Lichen Nitidus and Morphea

Lichen nitidus and morphea are common diseases, but an associated localization of both lesions is rare. Here, we describe the first case of lesions distributed along Blaschko's lines. A 24-year-old Japanese woman was referred to our clinic for evaluation of band-like plaques of 18-months history on the right lateral side of her abdomen. In addition, multiple milky-white papules were seen within the plaques. Histopathological examination showed there was sclerosis in the lower half of the dermis and well-circumscribed, dense, papillary dermal lymphohistiocytic aggregations showing a so-called "claw clutching a ball." Immunohistochemical analysis revealed that the morphea and lichen nitidus had similar characteristics. We speculated that unique immunologic events led to the development of lichen nitidus and morphea in our patient.

Oral lichen nitidus case report

This case report aims to increase awareness that lichen nitidus may affect the mouth and therefore supports multidisciplinary management, particularly between dermatologists and dental professionals.

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.

Anterior Ectopic Cilia with Myopia and Lichen Nitidus: A Rare Case Report with Dermoscopic Findings

Ectopic cilia, or lash follicles situated over abnormal sites, are an extremely rare entity. Here, we report the case of a 6-year-old-boy who presented with ectopic cilia over the left upper eyelid along with a positive family history. Dermoscopy revealed discreet terminal hair emerging from the individual hair follicles surmounted over a diffuse structureless whitish-yellow zone and a few vellus hairs in the surrounding normal skin. These hairs, on histopathological examination, had multiple pilosebaceous follicular units embedded in a desmoplastic stroma with multiple eccrine sweat glands. Other incidental findings included lichen nitidus and myopia.

Lichenoid pseudovesicular papular eruption on nose: A papular facial dermatosis probably related to actinic lichen nitidus or micropapular polymorphous light eruption

Background

Facial papules are a feature of several clinical conditions and may present both diagnostic and therapeutic challenges.

Aim

To describe a grouped papular eruption on the nose and adjoining cheeks that has not been well characterized previously.

Materials and Methods

A series of consecutive patients with a papular eruption predominantly involving nose and cheeks were evaluated, treated and followed up prospectively at tertiary care centers. Demographic details, clinical features, histopathology and response to treatment were recorded.

Results

There were five men and six women (mean age 29.9 ± 6.9 years) who had disease for a mean duration of 17.3 ± 11.1 months. All patients presented with a predominantly asymptomatic eruption of monomorphic, pseudovesicular, grouped, skin colored to slightly erythematous papules prominently involving the tip of nose, nasal alae, philtrum and the adjoining cheeks. A total of 15 biopsies from 11 patients were analyzed and the predominant finding was a dense, focal lymphoid infiltrate restricted to the upper dermis with basal cell damage and atrophy of the overlying epidermis. The eruption ran a chronic course from several months to years.

Limitations

Direct immunofluorescence could not be performed except in one case. Immunohistochemical stains for CD4 and CD8 could not be done owing to nonavailability. Phototesting was undertaken in one patient only.

Conclusion

Small grouped papules on the nose and adjoining skin with a lichenoid histopathology appear to represent a distinct clinicopathological entity. It may be related to actinic lichen nitidus/micropapular variant of polymorphous light eruption.

Pediatric lichen nitidus: A single-center experience

OBJECTIVE

Lichen nitidus (LN) is an uncommon inflammatory skin eruption. The present study aims to describe a case series of children with LN seen at a tertiary-care health center.

METHODS

Retrospective study of 17 children with biopsy-proven LN between January 2007 and March 2017. Data related with epidemiologic, clinical, and histopathologic characteristics were recorded.

RESULTS

The mean age for the onset of LN was 9 years (range: 5-17 years), and the mean duration of the skin lesions was 13 months (range: 1-48 months). Fifteen were boys (88.2%). Seven children had a generalized form of LN (41.1%) and of these, two children had severe pruritus (11.8%). Seven children had a history of co-morbid skin conditions (41.1%), including lichen planus in one patient (5.9%), lichen striatus in one patient (5.9%), psoriasis and longitudinal ridges in the nails in one patient (5.9%), and cutaneous features of atopic skin in four patients (23.5%). All of the reviewed patients had lymphohistiocytic infiltration in the dermis and basal vacuolar degeneration. Multinucleated giant cells were present in 11 (64.7%).

CONCLUSION

This case series found LN in a generalized form as well as other concurrent dermatologic conditions in nearly half of those reported. The boy predominance was also noteworthy.

Differentiation of pityriasis rubra pilaris from plaque psoriasis by dermoscopy

Background

Diagnosing and differentiating pityriasis rubra pilaris (PRP) from other disorders can be a challenging task. Although histopathology remains the gold standard, it may not be feasible at times, especially in children. Being noninvasive, dermoscopy can be of great diagnostic importance in such a scenario. Dermoscopy overcomes the refractive properties of stratum corneum by interface medium or cross-polarization enabling easier visualization of lesions.

Objective

To study the dermoscopic features of PRP and compare them with dermoscopic features of psoriasis.

Patients and Methods

Retrospective observational analysis of dermoscopic characteristics of 28 patients with PRP (16) and psoriasis (12). Polarized dermoscopy at 10× magnification was performed and photographs were captured by Apple iPhone 7. The selection of dermoscopic variables was based on preexisting literature on the dermoscopic patterns of the 2 entities.

Results

The most frequent dermoscopic criteria of PRP were the presence of a central hair (16/16; 100%), follicular plugs (11/16; 68.7%), and perifollicular yellow/orange halos (9/16; 56.2%). No vascular structures were seen in our cases of PRP. Psoriasis was characterized by regularly distributed dotted vessels (12/12; 100%) and white scales (8/12; 66.6%).

Conclusions

Round-to-oval yellowish areas surrounding a central hair with or without follicular plugs represents the most frequent dermoscopic pattern of PRP.

Langerhans cell histiocytosis mimicking lichen nitidus with bone involvement

We report the case of a 6-month-old Hispanic boy with a 4-month history of widespread pruritic hypopigmented papules mimicking lichen nitidus. The final diagnosis was multisystem non-risk-organ Langerhans cell histiocytosis (LCH), with cutaneous and multiple bone involvement. With this patient and others previously reported in the literature, we suggest an early biopsy of the hypopigmented rash in children.

Generalized lichen nitidus successfully treated with narrow-band UVB phototherapy: two cases report

Lichen nitidus (LN) is an uncommon chronic inflammatory skin disease composed of numerous, tiny, shiny, flesh-colored papules that are predominantly observed on the chest, abdomen, glans penis and upper extremities. The distribution of LN is most often localized, but in some cases it can become generalized. Because LN tends to be asymptomatic and presents spontaneous resolution within several years, it usually does not require treatment except in symptomatic, persistent and generalized cases. We describe a 28-yr-old man and a 7-yr-old boy with generalized LN where both cases improved with narrow-band ultraviolet B (NB-UVB) phototherapy plus topical steroid ointment. Both patients noted improvement within the first three treatments and showed almost complete resolution after 18 and 20 treatments, respectively. NB-UVB phototherapy may be an effective alternative therapy for the treatment of generalized LN, even for those patients in their childhood.