Facial Granular Parakeratosis: The First Report of Combined Eccrine and Follicular Involvement

Abstract

Granular parakeratosis is a rare cutaneous disorder that typically affects intertriginous areas such as the axillae and groin. Non-intertriginous involvement is uncommon, and facial presentations are particularly rare. We report a case of a 40-year-old Thai woman with a two-year history of recurrent, pruritic, brownish, hyperkeratotic papules involving the face, neck, anterior chest, and upper back, without axillary or other typical flexural involvement. The lesions were aggravated by heat and sweating. Histopathological examination revealed focal compact parakeratosis with retained basophilic keratohyalin granules, extending into both the eccrine ostia and follicular infundibula, confirming the diagnosis of granular parakeratosis. Based on the available literature, this appears to be the first reported case of combined eccrine and follicular involvement. After a one-month follow-up, the patient showed marked improvement with topical corticosteroids and lifestyle modifications to reduce heat exposure.