A patient with reticular pigmentation

A 38- year-old man in good general health and normal intellectual functioning referred to the dermatologic clinic with numerous pruritic reticulate pigmentations on his neck, chest and upper back since 10 years ago. we noticed similar lesions on his axillae, groin and infra mammary area with no family background. upon examination, symmetrical multiple small, rounds, dark brown freckle -like macules on his flexural surfaces and pruritic papules with a smooth surface on his chest were observed (figure 1,2). hair and nail were normal. potassium hydroxide smear was negative. the patient was previously treated with topical hydroqinone, tretinoin, adapalene and corticosteroids with no response. a skin biopsy was preformed.