Clinical presentation

Eosinophilic folliculitis presents as intensely pruritic 2-3 mm erythematous oedematous urticarial papules centred on follicles and may have pustules. The distribution is over the forehead, neck, shoulders, trunk and upper arms. Occasionally it can become generalised. Due to the associated pruritus, secondary change with time is common. This includes excoriations with secondary staphylococcal infection, prurigo nodularis, lichen simplex chronicus and postinflammatory pigmentary changes.[163][164]

PPE appears as multiple papules, typically symmetric, on the trunk and extensor surfaces of the extremities, as well as on the face, with sparing of the palms and soles. Because of the chronic nature of PPE, the papules are often excoriated and develop inflammation, hyperpigmentation and scarring. Over time, severe inflammation causes the papules to become nodular in appearance.[165]