Sometimes the run-of-the-mill case of acne vulgaris is more than it seems. Here’s how to spot and treat common acne foolers. By Julie C. Harper, MD ne of the most common diagnoses made by a conversation about the need to follow the prescribed regimen, dermatologist, acne is easily recognizable by you move in closer for a visual inspection and notice that both physician and patient. In fact, the patient things look different than they did from across the room. The most often has made the diagnosis prior to diagnosis is not acne vulgaris at all. scheduling an appointment. So, a very busy Odermatologist picks up a chart that says, “Chief complaint: Finding the Clues acne vulgaris,” and walks into the exam room. From the door There are several simulators of acne vulgaris that can confound a the doctor can appreciate bumps on the face and maybe even clinician. Though these “imposters” can present with a clinical on the neck and chest. This patient is straightforward! The appearance similar to that of acne, closer inspection often reveals presentation is so clear that a diagnosis is made without close subtle (and sometimes not too subtle) clues that will point to the examination of the skin. Treatment is initiated and the patient true diagnosis. Some deserve special consideration: is scheduled for follow-up in eight weeks. Perioral dermatitis. Perioral dermatitis may certainly be The patient returns for follow-up in eight weeks with mistaken for acne vulgaris. It is seen most commonly in young absolutely no improvement. Of course, compliance is always to middle-aged females, a group that is also susceptible to acne an issue! As you visit with the patient, preparing to ease into a vulgaris. It may be associated with inflammatory acne-like 26 Practical Dermatology August 2006 be seen together. Often the patient presents with an acne con- globata-like appearance. Alternatively, they may have been treated with antibiotics or even isotretinoin with what is con- sidered only a partial response. Some dermatologists might be tempted to prescribe additional courses of isotretion aimed at these resistant acne “cysts.” True epidermoid cysts will not show significant improvement with oral antibiotics or isotretinoin. They are best treated with surgical excision. Rosacea fulminans. Not to be confused with acne fulmi- nans, rosacea fulminans presents in young to middle-aged adult females with a history of minimal acne. Seemingly out- papules that involve the of-the-blue, these individuals go from having clear skin to chin, jawline and nasolabial folds. As the name being disfigured with large inflammatory nodules and pustules. implies, perioral dermatitis is also a dermatitis and therefore is Again the comedo, the hallmark of acne vulgaris, is absent. As associated with redness, dryness and itching. Remember that in acne fulminans, systemic symptoms may be present. the area immediately adjacent to the vermillion border will be Treatment includes systemic steroids alone for weeks to months spared. Acne vulgaris may also affect the perioral skin, particu- followed by a combination of systemic steroids and larly in adult females. What helps to differentiate perioral der- isotretinoin. Once the inflammation appears to be well con- matitis from acne vulgaris is the absence of the comedo. trolled the steroids may be discontinued and isotretinoin con- Unless there is an overlap between perioral dermatitis and tinued appropriately. acne vulgaris, comedones should be absent. Fortunately, treat- Syringomas. Occasionally an appendageal tumor will mask ment is similar for both with tetracycline antibiotics often lead- as acne vulgaris. Eruptive syringomas present around puberty ing to resolution of perioral dermatitis within eight weeks. and may be seen on the face, upper chest and upper back, all However, the typical topical treatments for acne vulgaris areas prone to acne vulgaris. Treating eruptive syringomas is dif- including topical retinoids and benzoyl peroxide may con- ficult. Ablative lasers may offer some cosmetic improvement. tribute to the dryness and irritation associated with perioral Pityrosporum folliculitis. Pityrosporum folliculitis is prob- dermatitis. ably mistaken for acne more often than any of us know. It is Verruca plana. Numerous flat warts can also be mistaken seen most commonly on the trunk in the same distribution as for acne vulgaris. They are small, skin-colored, non-inflamed tinea versicolor. It is characterized by erythematous, follicular papules that may occur anywhere on the body. When they are papules and small pustules and is notoriously itchy. Treatment localized to the face or upper trunk they may mimic come- includes systemic antiyeast medications, including itraconazole donal acne. However, on close inspection, the lesions are not or fluconazole. centered around a follicle and no comedones are visible. Flat Demodex folliculitis. Demodex folliculorum is a mite warts may respond to topical retinoids but may require addi- present in the sebaceous follicles on the face. Whether or not tional treatments, including cryotherapy, imiquimod, and/or Demodex incites inflammation is controversial. However, it is immunotherapy. worth considering Demodex folliculitis in individuals with an Multiple epidermoid cysts. Epidermoid cysts are some- asymmetric, itchy papular eruption on the face. Demodex fol- times confused with nodulocystic acne. The two entities may liculitis has also been reported in patients with HIV. Treatment August 2006 Practical Dermatology 27 Acne Imposters Don’t Be Fooled By Acne Imposters Imposter Clues Treatment Options Perioral dermatitis Area immediately adjacent to the ver- Tetracycline antibiotics; Typical topical million border will be spared; No treatments for acne vulgaris (retinoids comedones visible and benzoyl peroxide) may contribute to dryness and irritation. Verruca plana Lesions not centered around a follicle; Topical retinoids; Additional treat- No comedones visible ments include: cryotherapy, imiquimod, and/or immunotherapy Multiple epidermoid cysts Non-response to oral antibiotics or Surgical excision isotretinoin Rosacea fulminans Absent comdedo; Possible systemic Systemic steroids + oral isotretinoin symptoms; No or minimal history of acne Syringomas Skin-colored papules not centered Ablative lasers around a follicle; no comedones visible Pityrosporum folliculitis Notoriously itchy Systemic antiyeast medications, incl. itraconazole or fluconazole Demodex folliculitis Asymmetric, itchy papular eruption Topical permethrin; Topical or oral on the face metronidazole; Ivermectin orally for resistant cases Gram–negative folliculitis Initial therapeutic response followed Oral isotretinoin by acne flares; Large inflamed crusted papules around nose and mouth Tinea faceii and tinea Annular, erythematous or pustular Antifungals; For deep-seated pustules, barbae eruption systemic therapy likely necessary Sarcoidosis Apple jelly color lesions; Comedones Topical, intralesional or systemic absent; Systemic symptoms in patients steroids, hydroxycholoroquine, with systemic sarcoidosis. minocycline Keratosis pilaris Red, follicular, hyperkeratotic papules Topical retinoids, alpha-hydroxy acids, on the cheeks; Similar changes on the or topical salicylic acid; Low-potency upper extensor arms, buttocks, or topical steroid thighs Rosacea Comedo absent; Papules not always Physician preferred regimen for centered around follicle; rosacea. Telangiectases and facial erythema; History of flushing, triggers (esp. sun- light) Pseudofolliculitis barbae Ingrown hairs evident; Comedones Tetracyclines diminish inflammation; absent Topical retinoids (fordesquamation, to lighten PIH) Eosinophilic folliculitis Often pruritic; May be intermittent, UV therapy; Antipruritics; Systemic alternating periods of flaring and steroids clearing 28 Practical Dermatology August 2006 includes topical permethrin and/or topical or oral metronida- Acne rosacea. Is it acne vulgaris or is it rosacea? Making this zole. Resistant cases may benefit from ivermectin orally. distinction can be more challenging than it initially appears at Gram–negative folliculitis. Gram-negative folliculitis is first blush (no pun intended). Remember that the primary seen in individuals who have known acne vulgaris. These indi- lesion of acne is the comedo. This lesion should be readily viduals have been on numerous antibiotics for relatively long apparent in acne vulgaris and absent in rosacea. Rosacea periods of time. They may have had an initial excellent papules are also not always centered around the follicle and response, but as the lesions become infected with gram nega- telangiectases and facial erythema may be promininent. tive organisms, the acne flares with large inflamed crusted History may also offer some clues to the correct diagnosis. Ask papules around the nose and mouth. Although the name about a tendency to blush easily and ask what effect sunlight would imply that additional antibiotics are required for clear- has on the condition. Sunlight is the most frequently implicat- ing, the treatment of choice is oral isotretinoin. ed exacerbating factor in rosacea. Patients with acne vulgaris Tinea faceii and tinea barbae. Tinea faceii or tinea barbae often report that their acne improves with sunlight exposure. may be very subtle. It may present in any age Pseudofolliculitis barbae. PFB is not acne but group as an annular, erythematous or pustu- Always certainly does look like it. Inflammatory lar eruption. If the patient already has a papules and