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SF | DERMATOLOGY
January 2022 | Vol. 22 No. 1 www.medicalacademic.co.za
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This article was independently sourced by Specialist Forum.
Treating superficial skin infections
Topical antibacterials are commonly used for superficial skin infections, cuts, abrasions, burns, and surgical wounds. Several topical antibiotics are available for use in different indications. Impetigo and folliculitis are two of the most common bacterial skin infections seen in primary care and fusidic acid is indicated as first-line option for both.1,2,6,7
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mpetigo is a common superficial bacterial infection most often seen in children. There are two forms of impetigo non-bullous and bullous. The non-bullous form is the most common (70%) and generally affect children between two and five years, while those under the age of two are more affected by the bullous form.3 The non-bullous form presents with an erosion (sore), cluster of erosions, or small vesicles or pustules that have an adherent or oozing honey-yellow crust. The bullous form of impetigo presents as a large thinwalled bulla (2cm to 5cm) containing serous yellow fluid. It often ruptures leaving a complete or partially denuded area with a ring or arc of remaining bulla. 2,3 Lesions can develop anywhere on the body but are most common on the face. It is a self-limiting, non-scarring condition, which usually resolves in two to three weeks without treatment. 3 Complications are uncommon. However, untreated individuals remain infectious. To prevent outbreaks, children should not attend school or other childcare institutions until lesions are crusted and healed, or for 48 hours after commencing treatment. Good hygiene measures (eg washing hands regularly and using separate towels) help prevent spread of impetigo to other areas of the body and to other people.3 Folliculitis is caused by bacterial infection of the superficial or deep hair follicle. However, this condition may also be caused by fungal species, viruses and can even be non-infectious in nature. Several of the causative agents of folliculitis are listed below and include:4 _ Superficial bacterial folliculitis: the most common form of folliculitis, this particular condition is usually caused
by the bacteria S. aureus. It should be noted that both the methicillin-sensitive and methicillin-resistant forms of this bacteria can cause folliculitis. _ Gram-negative bacterial folliculitis: commonly referred to as ‘hot tub’ folliculitis, this condition results from the bacteria pseudomonas aeruginosa. It typically arises after exposure to contaminated water from either an improperly treated swimming pool or hot tub. Other bacteria that may cause this condition include Klebsiella and Enterobacter. Folliculitis from these bacteria commonly arises after longterm use of oral antibiotics. _ Pityrosporum folliculitis: this particular form of folliculitis is fungal, caused by the Malassezia species of fungi such as Malassezia furfur. Typically found in adolescence secondary to increased activity of their sebaceous glands and is commonly found in a cape-like distribution over the patient’s shoulders, back, and neck. Clinical suspicion of this condition should arise in patients diagnosed with acne that has failed to respond or even worsened, after antibiotic treatment. _ Viral folliculitis: most commonly caused by herpes virus it could also be caused by Molluscum contagiosum, but this is far rarer. Folliculitis due to herpes virus presents in much the same way as bacterial folliculitis with the exception that papulovesicles and/or plaques are usually present and not pustules. Another key to the diagnosis of this condition is that lesions typically appear in either groups or clusters. _ Demodex folliculitis: a type of folliculitis caused by the mite Demodex
folliculorum. this particular type of folliculitis is controversial as the Demodex mite normally presents in the pilonidal sebaceous area of the skin. Estimates are that 80% to 90% of all humans may carry this mite. _ Eosinophilic folliculitis: this particular brand of folliculitis is found predominantly in those with advanced HIV or those with low CD4 counts. Although a nonHIV variation of this condition has been seen as a rare side effect in patients undergoing chemotherapy. While the exact aetiology of this condition is unknown, studies suggest it could result from inflammatory disease secondary to immune dysregulation and that there may be an associated underlying infection. Most commonly, this condition presents as erythematous and urticarial follicular papules, usually on the scalp, face, and neck with rare pustules.
Oral or topical antibiotics? According to current recommendations, topical antibiotics are only recommended in cases of mild to moderate or superficial infections. Patients with severe disease who are systemically unwell will require assessment in hospital for monitoring and intravenous antibiotics.5 Fusidic acid and mupirocin are two of the most commonly used antibiotics for the treatment and eradication of skin infection. Topicals antibacterials are eminently suitable for targeted drug delivery by taking the drug directly to the site of action, thus ensuring excellent bioavailability of antimicrobials at the infected tissue. The other advantages of topical usage of antimicrobials are the small amounts of drugs used, low cost, and noninterference with intestinal microbial flora.1
