Comedones (2 of 2)

Differential Diagnoses

Important differential diagnoses include:

• demodicosis (caused by Demodex mites which live in the follicles)
• endocrine diseases (hair growth is reduced and scale formation often occurs)
• primary defects of keratinisation such as idiopathic seborrhoea (genetic defect in basal keratinocytes leads to excessive scale production)

Clinical tip in dogs: skin scrapes and hair plucks for Demodex are essential first tests in dogs which present with comedones.