7th June 2025

Folliculitis

Folliculitis describes inflammation of the hair follicles, but the term is usually used in the context of bacterial infection, mostly commonly with Staphylococcus aureus. This presents with inflamed papules and pustules (see Figure). It often affects the back. It may occur on the legs or pubic area, as the infection may be spread via shaving or waxing.

Image Source: Wikimedia Commons (2021). Purulent rashes on the neck of a Man – Allergy Acne Skin Disease, Licensed under a creative commons licence. https://www.istockphoto.com/photo/purulent-rashes-on-the-neck-of-a-man-allergy-acne-skin-diseases-gm1302757001-394401309?phrase=bacterial+folliculitis (Accessed 23 May 2025).

Investigations

• Nasal swab to check for staphylococcal carriage
• Swab of pus will typically show S. aureus; sensitivities may be helpful to guide treatment. Other potentially causative bacteria include Pseudomonas aeruginosa or other Gram negative organisms. 
• A biopsy is rarely indicated for refractory or atypical disease. Fungal/yeast infection is sometimes found mimicking bacterial infection (and should be treated accordingly).

Management

• For very mild disease, no treatment may be necessary
• Stop/minimise shaving or waxing the area (if relevant)
• Antiseptic washes
• Eradicate nasal staphylococcal carriage if found (as this is a potential source of recurrent disease)
• Consider topical antibiotic for localised disease (e.g. clindamycin lotion)
• Oral antibiotic, e.g. flucloxacillin, for 1-2 weeks for acute disease
• Prolonged course (e.g. 3-6 months) of oral antibiotic, usually lymecycline or doxycycline, for chronic disease