Dermatitis

Can you identify these flesh-colored papules?

SAILAJA GHANTA, MD and CHANDAN N. LAKHIANI, MD
Hasbro Children’s Hospital

Dr Ghanta is a third-year pediatric resident and Dr Lakhiani is assistant professor of pediatrics at Hasbro Children’s Hospital in Providence, RI.

Kirk Barber, MD, FRCPC––Series Editor: Dr Barber is a consultant dermatologist at Alberta Children’s Hospital and clinical asso-ciate professor of medicine and community health sciences at the University of Calgary in Alberta.

Dermclinic 
Lichen NitidusCase:
This 5-year-old boy has had a generalized, mildly pruritic rash for the past month. The eruption first appeared on the forehead and then spread to the abdomen, back, arms, and legs. The child is otherwise well. He has no history of fever. He does not take any medications. No one else in the family has a similar rash.

On examination, the child appears comfortable. He has multiple pinhead-sized, flesh-colored papules concentrated on the face, abdomen, and upper extremities, with scattered lesions on the back and lower extremities. Some of the lesions are arranged in a linear pattern, especially on the forehead and right forearm.

Can you identify these flesh-colored papules?

(Answer on next page.)Lichen Nitidus

Dermclinic - Answer 

The lesions are characteristic of lichen nitidus.

Lichen NitidusLichen nitidus is a benign dermatosis that can affect persons of all ages but most frequently young children. This relatively uncommon chronic papulosquamous disorder is characterized by 1 to 2-mm, flesh-colored (may be hypopigmented in dark-skinned persons) papules with a smooth, shiny surface. The lesions primarily occur on the extremities, trunk, abdomen, and genitalia. The rash may develop in a linear fashion in areas of trauma (ie, Koebner phenomenon). Rarely, the palms, soles, nails, and mucous membranes may be involved. Generalized, linear, actinic, perforating, vesicular, purpuric, and hemorrhagic variants of the disorder have been described.

The exact cause of lichen nitidus is unknown. It has been associated with lichen planus, atopic dermatitis, Down syndrome, and Crohn disease. Some experts consider lichen nitidus to be a variant of lichen planus.

Although the diagnosis of lichen nitidus is mostly clinical, when in doubt, it can be confirmed with a biopsy of the affected area. The histologic feature of a “hand clutching a ball” is pathognomonic. The “ball” is a lymphohistiocytic aggregation in the dermis, with a claw-like projection of the rete ridges around the infiltrate simulating the clutching fingers.

The clinical course of lichen nitidus is variable. The rash may clear spontaneously within weeks to months. The prognosis is good.Lichen Nitidus

There is no known effective treatment. In selected cases, topical corticosteroids may be used. Other forms of treatment used include oral corticosteroids, oral antihistamines, topical retinoids, topical tacrolimus, and astemizole (a second-generation antihistamine). There are reports of stubborn cases that responded to psoralen and UV-A therapy and narrow-band UV-B phototherapy.

We treated this patient with a mild topical corticosteroid. He returned to our clinic 3 months later, by which time, the rash had mostly resolved. Some lesions persisted on the forehead. 

FOR MORE INFORMATION:

■ Henry M, Metry DW. Generalized lichen nitidus with perioral and perinasal accentuation, in association with Down syndrome. Pediatr Dermatol. 2009;26:109-111.

■ Kim YC, Shim SD. Two cases of generalized lichen nitidus treated successfully with narrow-band UV-B phototherapy. Int J Dermatol. 2006;45:615-617.

■ Scheinfeld NS, Teplitz E, McClain SA. Crohn’s disease and lichen nitidus:a case report and comparison of common histopathologic features. Inflamm Bowel Dis. 2001;7:314-318.

■ Tilly JJ, Drolet BA, Esterly NB. Lichenoid eruptions in children. J Am Acad Dermatol. 2004;51:606-624.