Conflicts of interest: none declared. Sir, Perifolliculitis capitis abscedens et suffodiens (dissecting cellulitis or dissecting folliculitis) manifests with perifollicular pustules, nodules, abscesses and sinus tracts on the scalp, eventually resulting in extensive scarring alopecia. When it is associated with acne conglobata and hidradenitis suppurativa the syndrome is referred to as the follicular occlusion triad, and when also with pilonidal cysts as a tetrad.1 The frequent association of these diseases suggests a common pathogenesis. Its course is chronic and relapsing, and treatment is frequently difficult. Therapies include isotretinoin, antibiotics, prednisone, X‐ray therapy, surgical excision and skin grafting.2 Tumour necrosis factor (TNF) is a proinflammatory cytokine that seems to play an important role in the pathogenesis of these diseases. Infliximab is a chimeric monoclonal antibody that binds specifically to TNF‐α, decreasing the effect of the cytokine in inflammatory diseases. Infliximab monotherapy has been shown to be an effective therapeutic alternative for severe extensive forms of hidradenitis suppurativa.3