Publish date: Posted on
Last updated: February 17, 2024
Keywords #
folliculitis
hair follicle
Diagnosis #
Folliculitis refers to inflammation of the hair follicle. It may be due to occlusion, irritation, or infection. Infections can be caused by bacteria, viruses, fungi or parasites. The most common infectious cause is Staphylococcus Aureus. Less common types of folliculitis include HIV-associated eosinophilic folliculitis and drug-induced folliculitis.[1] Folliculitis may affect the superficial or the deep portion of the hair follicle. Mild cases are often self-resolving, but systemic treatment may be needed for persistent or recurrent cases.
Key Concepts #
- Folliculitis is inflammation of hair follicles.
- It may be due to infectious or non-infectious causes.
- Mild cases may be self-limiting, while more severe cases will require treatment.
Epidemiology #
The exact incidence of folliculitis is unknown.[2] Gender does not correlate with incidence but does correlate with type of folliculitis(for example, fungal folliculitis due to Malassezia is more common in men than women).[2, 3] Folliculitis is more commonly seen in immunosuppressed patients, those who shave frequently or patients with a history of diabetes and obesity. It may also be observed in patients with prolonged antibiotic use.
Clinical Features #
- Superficial folliculitis presents with ~1mm pustules, vesicles and erythematous papules.[1]
- Deep follicular inflammation can present as erythematous nodules.
- Lesions may be asymptomatic, pruritic, or tender.
Differential Diagnoses #
- Acne vulgaris
- Folliculitis
- Keratosis pilaris
- Rosacea
- Perioral dermatitis
- Tinea (tinea corporis, tinea capitis, tinea cruris, tinea pedis, barbae)
- Scabies
- Acne keloidalis nuchae
- Grover’s disease
- Hidradenitis suppurativa
Diagnostic Workup #
A diagnosis can often be made based on history and clinical findings. If the etiology is unclear, bacterial/viral/fungal cultures, viral PCR, or KOH preparations can be used to guide treatment. If MRSA is suspected, a culture is recommended.[4]
Treatment #
Treatment depends on the etiology of the folliculitis, but ensuring a healthy immune system and stopping any practice that is suspected to be causing the folliculitis (i.e. shaving, plucking, tight clothing, or waxing) is recommended in all cases. Patients should also be educated on proper hygiene and use warm compresses in the area. Many mild cases are self-limiting and do not require treatment. More severe bacterial, fungal and parasitic folliculitis can be treated with antibiotics, antifungal or anti-parasitic medications respectively. Topical antibiotics are typically first-line before a trial of oral antibiotics.[5] If viral folliculitis is suspected, oral antivirals can be prescribed.
Slide Viewer #
https://utahderm.med.utah.edu/image-viewer/References #
- Luelmo-Aguilar J, Santandreu MS. Folliculitis: recognition and management. Am J Clin Dermatol. 2004;5(5):301-310. doi:10.2165/00128071-200405050-00003
- Winters RD, Mitchell M. Folliculitis. [Updated 2020 Aug 11]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK547754/
- Suzuki C, Hase M, ShimoyamaH, Sei Y. Treatment Outcomes for Malassezia Folliculitis in theDermatology Department of a University Hospital in Japan. Med Mycol J. 2016;57(3):E63-6.
- Cohen PR. Community-acquired methicillin-resistant Staphylococcus aureus skin infections: implications for patients and practitioners. Am J Clin Dermatol. 2007;8(5):259-270. doi:10.2165/00128071-200708050-00001
- Lopez FA, Lartchenko S. Skin and soft tissue infections.Infect Dis Clin North Am. 2006;20(4):759-vi. doi:10.1016/j.idc.2006.09.006
