Hypopigmented papules over the chest.

A 30 year old male presented with multiple, non-pruritic hypopigmented papules over upper one-third of his chest since one year. These lesions at their onset were few in number and pruritic, with no history of trauma preceding their occurrence. The patient also reported past usage of topical steriods with intermittent relief in itching, but no improvement in the physical appearance of these eruptions.

General physical examination was unremarkable. Dermatological examination revealed multiple small, smooth, ivory white, flat topped papules with interspersed prominent brown coloured follicular plugs over the ‘V’ of the chest [Figure 1]. There were no lesions elsewhere on the body. Genitalia appeared normal. Histopathology of the biopsy of the papule revealed epidermal atrophy, flattened interpapillary crests, a band-like lymphocytic inflammatory infiltrate and dilated vessels in the upper dermis and homogenisation of collagen [Figure 2].

Figure 1

Grouped hypopigmented polygonal papules over the ‘V’ of the chest

Figure 2

Histopathology showing epidermal atrophy, homogenisation of collagen bundles and upper dermal lymphocytic infiltrate. (H and E, ×100)

Diagnosis

Extragenital lichen sclerosus et atrophicus.

Discussion

Lichen sclerosus et atrophicus (LS) is a rare chronic inflammatory dermatoses that occurs in individuals of any age, with highest prevalence in children below ten years and post menopausal women.[12] Women are affected ten times more than men,[34] and this decreased occurrence in men could be attributed to their early circumcisions.[3] Francois Henri Hallopeau first clinically described LS in 1887,[123] and it was Darier who described the characteristic histological findings in 1892.[1] It occurs predominantly in the genital area (83-98% of all cases) with 15-20% of them also having extragenital involvement; and rarely in 2.5% cases with lesions solely confined to an extragenital site, as were observed in our patient.[1]

The etiology of this dermatoses is unknown but genetic susceptibility appears to play a role in the disease. Its association with HLADQ7 and co-occurence of diseases like Hashimoto's thyroiditis, vitiligo and type 1 diabetes also indicates possible autoimmune process involvement in its causation.[134] Koebnerisation is common in lichen sclerosus – scarring or trauma produce typical skin lesions of the disorder. Extragenital lesions mostly occur over pre-existing scars or damaged areas.[1]

‘Craurose vulvar’ refers to the genital form of the disease in women that manifests as severely pruritic lesions resulting in painful erosions, vulvar atrophy that progresses to narrowing of the vaginal opening and dyspareunia. In men, the genital form is known as ‘balanitis obliterans xerotica’, that presents with painful itching, erosions and fissures.[4]

Extragenital lesions are porcelain white papules, plaques, or atrophic patches that may be surrounded by an erythematous or violaceous halo with folliculocentric keratin plugs overlying follicular ostia as observed in our case. Commonest sites include upper anterior torso, neck, arms and legs, ear, face, oral mucosa and nose. Hemorrhagic transformation often occurs and this appears to be due to basal cell degeneration that results in a weak dermal-epidermal junction.[134] Extragenital LS shows decreased expression of the proliferation marker Ki-67 and p53 in comparison to genital LS, and hence decreased malignant transformation in the former type.[35]

Diagnosis is clinical and histopathological. Treatment includes high-potency topical steroids, immunomodulators and systemic retinoids. Combined treatment with 0.1% tacrolimus ointment and PUVA serve as a good option in extensive cases of lichen sclerosus or when other treatment modalities have failed.[3] Low-dose UVA1 phototherapy is well tolerated and an effective alternative.[6] Cryosurgery, vulvectomy, CO2 laser, have been tried with high recurrence rates.[3] Our patient was advised, twice daily application of 0.1% tacrolimus ointment with subsequent relief.