INTRODUCTION: Follicular mucinosis is a rare skin condition, which can present as an idiopathic benign condition or as a secondary symptom of a malignant disorder, most commonly mycosis fungoides. Since its first description in 1957, only 90 cases have been reported worldwide. This condition is characterized by erythematous infiltrated plaques with scaling, sometimes with follicular prominence on the head and neck. Definitive diagnosis is made histologically. CASE: A 32-year old male presented with a 3- year history of recurrent scaling with eruption of pruritic erythematous papules and plaques over the face, neck and chest. Different local treatments (topical corticosteroids, antifungal cream and moisturizers) were ineffective. Overall, he was healthy. Histopathological examination of the lesion showed typical histological picture of follicular mucinosis. Alcian blue stain was positive. The patient was successfully treated with narrowband UVB (NB-UVB) therapy with no recurrence of lesions after one- month follow-up. CONCLUSION Idiopathic follicular mucinosis is a benign condition with localized involvement and excellent prognosis. However, long-term follow-up and monitoring is recommended because of its association with malignancy. Follicular mucinosis is a rare dermatosis, characterized histologically by the presence of mucin deposits within the hair follicle and sebaceous glands.1 There are three clinical types determined. The first and the most common type occurs as an idiopathic benign disorder, typically seen in young patients. The second type affects people 40-70 years of age and has a more chronic course. The third type usually occurs in the elderly and presents with widespread lesions. It can arise as a secondary symptom of a malignant disorder, most commonly mycosis fungoides.

Urticaria pigmentosa (UP) is the most common form of cutaneous mastocytosis in children. It can be diagnosed clinically, based on the appearance of numerous brownish macules and papules that are symmetrically distributed, mostly on the trunk and the extremities. Skin biopsy is helpful in establishing the diagnosis. Treatment options generally include antihistamines and/or topical corticosteroids. In most cases, pediatric UP tends to disappear spontaneously before puberty. We present the case of a 9-month-old male with a history of multiple brownish patches and plaques, which started when he was four months old. He was diagnosed with UP based on clinical and histopathologic findings, and was prescribed oral antihistamines and emollients for symptomatic treatment.
cutaneous mastocytosis ; mast cell degranulation