Peculiar facial erythematosquamous lesions in two siblings with cyclical summer improvement and winter relapse: a variant of keratosis lichenoides chronica?

[Keratosis lichenoides chronica in two siblings with marked response to UVB phototherapy]

BACKGROUND

Keratosis lichenoides chronica (KLC) is a rare chronic keratinisation disorder. Out of almost 60 published cases of KLC, only two report its occurrence in siblings. We report a new case in which a brother and sister present KLC that improved markedly with UVB phototherapy.

PATIENTS AND METHODS

A 10-year-old girl presented with hyperkeratotic papules symmetrically arranged in a reticular pattern on the face and the extremities. Onset occurred at the age of six months. For a number of years, minimum sunlight was allowed owing to a diagnosis of lupus. However, KLC was our first diagnostic assumption, confirmed by an elbow lesion biopsy sample. The patient's brother, one and a half years old, had been presenting similar lesions since the age of two months. Sibship was demonstrated by DNA analysis using short tandem repeat markers. No consanguinity was found. After one month of narrow-band UVB phototherapy, most of the papules had flattened.

DISCUSSION

KLC is uncommon in childhood and familial occurrence is very rare. Clinically, thick keratotic papules arranged in parallel lines or small networks cover the dorsal aspects of the limbs symmetrically. The face may be affected by a seborrhoea-like dermatitis. Histology typically shows alternating acanthosis and atrophy, with focal parakeratosis. An extensive lichenoid lymphohistiocytic and plasmocytic infiltrate is demonstrated in the dermis. The course is chronic. Spontaneous resolution may occur. Sunlight has been shown to be effective in the few paediatric cases reported. Narrow-band UVB phototherapy appears to be an effective therapeutic option.

Keratosis lichenoides chronica in an Indian child following erythroderma

A 4-year-old boy presented with mildly itchy, linear, skin lesions over the trunk, arms, and face of 3 months' duration. He had previously been admitted to a private hospital for generalized exfoliation of the skin following drug intake for fever and throat pain. The nature of the drugs was not known. The exfoliative dermatitis was treated with oral prednisolone, 10 mg daily, tapered over 3 weeks. No further topical or oral medication was given. The present skin lesions started 1 month after the cessation of the steroids. There was no family history of skin lesions, voice changes, or systemic complaints. Cutaneous examination showed multiple violaceous, linear, reticulate ridges with adherent scaling over the chest, back, and neck. There were scaly, flat-topped papules over the extensor aspects of both upper arms and the buttocks, and scaly plaques over the cheeks (Figs 1a-d and 2a,b). The scalp showed diffuse greasy scaling. There were no oral, genital, axillary, or eye lesions. The nails were normal. Systemic examination did not reveal any abnormal finding. Routine hematologic investigations, liver and kidney function tests, tests for hepatitis B and C, and enzyme-linked immunosorbent assay (ELISA) for HIV were normal. Histopathology from skin lesions on the back revealed hyperkeratosis, patchy parakeratosis, follicular plugging, alternating irregular acanthosis and epidermal thinning, basal cell degeneration, and a band-like inflammatory infiltrate of lymphocytes, histiocytes, and a few plasma cells (Fig. 3). Based on the classical clinical features and histopathology, keratosis lichenoides chronica was diagnosed, and topical 1% hydrocortisone acetate cream, twice daily, was prescribed. There was slight relief of pruritus at a follow-up visit after 3 weeks; however, the patient was subsequently lost to follow-up.

Keratosis lichenoides chronica in pediatric patients: A different disease?

Keratosis lichenoides chronica (KLC) is a rare acquired disease of adulthood, of unknown etiology, characterized by keratotic parallel linear lesions, retiform plaques, and keratotic, often follicular papules, chronicity and lichenoid histopathologic features. KLC of pediatric onset is considered extremely rare. Its features and relationship to adult onset KLC are unknown. We studied 8 cases of pediatric-onset KLC in the literature and 6 personal cases and compared them with 40 reported adult-onset KLC patients. The following features characterize pediatric-onset KLC: familial occurrence; probable autosomal recessive inheritance; early or congenital onset with facial erythemato-purpuric macules; forehead, eyebrow, and eyelash alopecia; pruritus; and a low frequency of other cutaneous and systemic abnormalities. Pediatric-onset KLC may represent a different disease or a subset of adult-onset KLC, with special genetic and clinical characteristics. Determining its precise nosology will have prognostic and therapeutic implications.

Keratosis Lichenoides Chronica: Proposal of a Concept

It has been a subject of controversy whether keratosis lichenoides chronica (KLC) is a distinctive inflammatory disease of the skin or whether it represents a manifestation of another well-known disease, such as lichen planus, lupus erythematosus, or lichen simplex chronicus. In search of clear criteria for diagnosis of KLC the entire literature pertinent to the subject was studied and findings clinical and histopathologic as they were telegraphed in them were compared with a patient of my own experience. Review of the literature reveals more than 60 patients in whom the diagnosis of KLC was made. Three categories emerge based on whether the findings presented in a particular article (1) do not permit any diagnosis to be rendered; (2) do allow a diagnosis specific to be made, such as of lichen simplex, lichen planus, or lupus erythematosus; or (3) do not correspond to any disease well defined, such as lichen simplex, lichen planus, lupus erythematosus, but seem to show attributes morphologic, clinically and histopathologically, that are repeatable. Patients diagnosed as having KLC obviously represent a potpourri of different diseases, the most common of them being lichen simplex chronicus, lichen planus, and lupus erythematosus. Fewer than 25 patients reported on, however, presented themselves with lesions very similar to one another clinically, namely, an eruption that involved the face in a manner reminiscent of seborrheic dermatitis and with tiny papules on the trunk and extremities, which assumed linear and reticulate shapes by way of confluence of lesions. Individual papules were infundibulocentric and acrosyringocentric. Findings histopathologic were those of a lichenoid interface dermatitis affiliated with numerous necrotic keratocytes and covered by parakeratosis housing neutrophils in staggered fashion. These patients seem to have an authentic and distinctive condition that is exceedingly rare. In conclusion, the diagnosis of KLC should be made only for patients who present themselves with features clinical and findings histopathologic that resemble closely those of what is summarized in this article under category 3.

Keratosis lichenoides chronica in childhood

Keratosis lichenoides chronica (KLC) is a rare chronic disorder of keratinization characterized by lichenoid hyperkeratotic papules arranged in a linear pattern, erythematosquamous plaques and seborrhea-like dermatitis on the face. We report a 2-year-old girl diagnosed with KLC whose lesions, arranged in symmetrical linear fashion, improved after sunlight exposure during the summer.