thought to cause disrupted skin barrier function.23 At this time, it is unclear how a more acidic or lower pH in truncal skin may contribute to acne development.
In addition to physiologic characteristics, the trunk is frequently under occlusion from clothing or sporting gear rendering truncal skin more affected by mechanical effects, such as trapped sweat/ oils, pressure, and friction, than facial skin.24 These contribute to comedone formation and inflammation. One pilot study in young males over 12 years of age with truncal acne revealed a trend toward acne exacerbation due to exercise-induced sweat 5 days per week for 2 weeks.25 Statistical significance was not achieved, but this is likely due to the small sample size of the study (N=23).
In addition to physiologic characteristics, the trunk is frequently under occlusion from clothing or sporting gear rendering truncal skin more affected by mechanical effects, such as trapped sweat/ oils, pressure, and friction, than facial skin.24 These contribute to comedone formation and inflammation. One pilot study in young males over 12 years of age with truncal acne revealed a trend toward acne exacerbation due to exercise-induced sweat 5 days per week for 2 weeks.25 Statistical significance was not achieved, but this is likely due to the small sample size of the study (N=23).
TRUNCAL ACNE SEVERITY ASSESSMENT
Numerous tools have been developed to assess the severity of truncal acne, such as the Leeds technique and Physician Global Assessment (PGA).5,26 These generally assess severity based on anatomic extent of disease and number of inflammatory/noninflammatory lesions. One tool was also developed to assess the severity of acne scars on the face and trunk.27 However, none have been suitable for daily clinical practice, nor have they incorporated the psychological and QoL impact of the overall severity of the disease. To address this, the truncal acne severity scale (TRASS) was recently developed and validated.28 TRASS is a comprehensive assessment tool that goes beyond the classical scoring based on the presence, type, and area of lesions. It incorporates a patient’s duration of acne, prior systemic acne treatment, family acne history, clinical signs such as nodules and scars, and anatomic location, as well as impact on QoL. TRASS is therefore the first acne severity assessment tool to combine global assessment with patient-centered metrics.
CURRENT TREATMENTS FOR TRUNCAL ACNE
Treatments that have generally been used for truncal acne have been adapted from facial acne. Some small studies have assessed their utility, but large controlled trials with truncal acne-specific efficacy endpoints have been lacking. The current evidence of the efficacy of these treatments for truncal acne are reviewed next (Table 1).
Antibiotics
Antibiotics serve a dual purpose in the treatment of acne given their anti-inflammatory and antibacterial effects. Topical antibiotics have been utilized for decades in the treatment of acne. A mainstay of treatment for acne is benzoyl peroxide (BPO). It is a potent antimicrobial agent effective for acne while also reducing the risk of antibiotic resistance. Its effectiveness in both facial and truncal acne is dependent on concentration and contact time with the skin. One study found short-contact
Antibiotics
Antibiotics serve a dual purpose in the treatment of acne given their anti-inflammatory and antibacterial effects. Topical antibiotics have been utilized for decades in the treatment of acne. A mainstay of treatment for acne is benzoyl peroxide (BPO). It is a potent antimicrobial agent effective for acne while also reducing the risk of antibiotic resistance. Its effectiveness in both facial and truncal acne is dependent on concentration and contact time with the skin. One study found short-contact
