What is the clinical presentation of folliculitis?

From the Guidelines

Folliculitis is characterized by small, red, painful or itchy bumps or pustules centered around hair follicles, typically appearing in areas with hair, such as the scalp, beard area, arms, back, buttocks, and legs. The condition may be superficial, limited to the upper part of the follicle, or deep, extending into the dermis, as noted in the practice guidelines for the diagnosis and management of skin and soft tissue infections 1. Superficial folliculitis appears as small pustules with surrounding erythema, while deep folliculitis presents as more nodular, painful lesions that may develop into abscesses. Patients often report tenderness, burning, or itching at the affected sites. The distribution pattern often reflects the causative factor, such as hot tub folliculitis typically affecting areas covered by swimwear, while bacterial folliculitis may cluster in areas subject to friction or occlusion. Key characteristics of folliculitis include:

• Small, red, painful or itchy bumps or pustules centered around hair follicles
• Appearance in areas with hair, such as the scalp, beard area, arms, back, buttocks, and legs
• Superficial or deep presentation, with superficial folliculitis limited to the upper part of the follicle and deep folliculitis extending into the dermis
• Systemic symptoms like fever are uncommon unless the infection is severe or widespread. Chronic folliculitis can lead to scarring, post-inflammatory hyperpigmentation, or hair loss in the affected areas, as differentiated from furuncles and carbuncles, which are infections of the hair follicle that extend into the subcutaneous tissue, forming a small abscess 1. Diagnosis is primarily clinical, based on the characteristic appearance of follicle-centered pustules, though culture may be necessary to identify specific pathogens in recurrent or resistant cases.

From the Research

Clinical Picture of Folliculitis

• Folliculitis is an inflammatory reaction in the superficial aspect of the hair follicle and can involve the follicular opening or the perifollicular hair follicles 2.
• The clinical manifestations of folliculitis can be classified according to their anatomical location and histopathologic patterns 2.
• Clinically, the inflammation manifests as 1mm-wide vesicles, pustules, or papulopustules in acute cases; however, hyperkeratosis and keratotic plug formations are indicative of a chronic process 2.
• The presence of superficial pustules does not always imply an infectious origin, as there are many noninfectious types of folliculitis 2.

Types of Folliculitis

• Folliculitis can be caused by bacterial infections, with Staphylococcus aureus and Streptococcus pyogenes being common causative agents 3.
• Folliculitis can also be induced by epidermal growth factor receptor (EGFR) inhibitors, with variations in terms of treatment-related incidence and intensity 4.
• Other types of folliculitis include folliculitis decalvans, a rare type of cicatricial alopecia 5.

Treatment and Management

• The treatment of folliculitis depends on the underlying cause and severity of the condition 6, 2, 5, 4, 3.
• Topical and oral antibiotics, such as cephalexin, doxycycline, and minocycline, are commonly used to treat bacterial folliculitis 6, 3.
• Tetracyclines have been recommended for the prophylaxis and treatment of folliculitis induced by EGFR inhibitors 4.
• Intralesional triamcinolone acetonide and clobetasol lotion may also be used to treat folliculitis decalvans 5.