A 55-year-old man presents with skin lesions that have come and gone over the past several years. The lesions cause minor pain and irritation. The patient admits to picking at the lesions. He has been seen elsewhere several times over the years for this condition, and each time received a prescription for an unknown antibiotic that led to improvement; however, the lesions always recurred after the 10- to14-day course of treatment. The patient is in good health otherwise, with no diabetes or immune suppression. Focal scarring, epidermal thickening, and hyperpigmentation are noted on the surfaces of the lesions, approximately one-third of which are modestly fluctuant. A small amount of pus can be expressed through follicular orifices from a few of the lesions and was sent for culture and sensitivity testing.
A 65-year-old woman presents with a pruritic skin condition that has persisted for more than 20 years. The patient is taking an oral antihypertensive medication and a sleep aid, but her skin condition had begun many years prior to being on any consistent oral medication. Hundreds of almost identical excoriated nodular scabbed lesions of approximately 1 to 2 cm are uniformly distributed on the patient’s trunk, arms, upper legs, and buttocks, but are absent from her palms, face, and the middle of her back. Very little erythema is seen around the lesions. Hundreds of scars from healed sites are also seen in the same areas. Her face and skin below the waist are free of notable lesions.
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Furuncles, commonly known as boils, is an infection of the hair follicle, with purulent material extending through the dermis into subcutaneous tissue. This can occur anywhere on the skin where there is hair. They are more common in areas with more friction and perspiration, including the back of the neck, face, axilla, and buttocks.
Furuncles usually occur after episodes of folliculitis and can coalesce together to form a single inflammatory lesion called a carbuncle. Systemic involvement is uncommon except in larger infections. Infection of the hair follicle by Staphylococcus aureus is the most common cause of furunculosis, and it can be caused by both methicillin-susceptible S aureus and methicillin-resistant S aureus (MRSA).
Risk factors include nasal carriage of S aureus. Those carrying MRSA may be at higher risk, though some studies have shown that nasal carriage of S aureus is not correlated with S aureus skin and soft tissue infection of any kind.1 In one pediatric study, rectal colonization by MRSA was strongly associated with increased risk of skin abscesses and furuncles.2 Those in close contact with others with known active infection are also at increased risk.
S aureus infection is the most common and accounts for approximately 75% of cases of furuncles.3 Recent studies have shown that strains of MRSA USA300 were virulent and highly prevalent in New York City.3 Colonization with other pathogens, such as Enterobacteriaceae, Enterococci, Corynebacterium, S epidermidis, and S pyogenes, may also put patients at higher risk for recurrence. Exposure to sitting water, such as hot tubs or whirlpools, increases the risk for pseudomonal or mycobacterial furunculosis.4
The most common complications of furunculosis include postinflammatory hyperpigmentation, scarring, and recurrence of lesions. Systemic symptoms and infections are rare. Cases of endocarditis following furunculosis have been reported.5 Those who are colonized with S aureus are at higher risk of recurrent furunculosis and can have 3 or more episodes in a period of 1 year.
Differential diagnosis includes folliculitis, hidradenitis suppurativa, sporotrichosis, leishmaniasis, tularemia, myiasis, botryomycosis, nontuberculous mycobacteria, blastomycosis, acne vulgaris, and neurotic excoriations.
Hidradenitis suppurativa presents as tender nodules with extensive scarring and sinus tracks primarily in the axillae, groin, and submammary areas. It can be differentiated from furunculosis by its distribution, more extensive scarring, sinus tracts, and occasional concomitant comedones.
Acne vulgaris presents as open and closed comedones with erythematous papules and pustules. It is usually distributed on the upper trunk, neck, and face. It can be differentiated from furunculosis by the history, presence of comedones, and distribution.
Sporotrichosis has 3 typical presentations. Lymphocutaneous sporotrichosis presents as painless erythematous nodules on the distal extremities following lymphatic flow. Fixed cutaneous sporotrichosis does not follow the lymphatic distribution and presents as verrucous or gummatous plaques most commonly on the face. Disseminated cutaneous sporotrichosis is diffusely distributed papules and nodules. Sporotrichosis can be differentiated from furunculosis based on distribution and history significant for sporotrichosis risk factors. A skin culture can help differentiate the etiology.
Treatment options for furuncles depend on size and severity. For smaller furuncles, warm compresses are usually sufficient to facilitate drainage of purulent material and resolution. Larger lesions may require incision and drainage. Material can be sent for culture and susceptibility testing in more resistant infections.
The use of antibiotics depends on a number of factors, including number and size of lesions, amount of cellulitis, associated medical conditions, immunosuppression, systemic symptoms, persistent infection, or whether there is a high risk of transmission (eg, athletes, military personnel). Generally, antibiotics are recommended only in cases in which patients have systemic symptoms and/or fit the criteria for systemic inflammatory response syndrome.6 In those with MRSA, options include vancomycin, linezolid, clindamycin, daptomycin, ceftaroline, doxycycline, minocycline, and trimethoprim/sulfamethoxazole.
In our case, the patient’s results showed MRSA that was sensitive to trimethoprim/sulfamethoxazole, clindamycin, and the tetracyclines, among other antibiotics. This organism quickly became the focus of treatment, although his clinical picture was confused by the fact that he was also a picker. This patient’s condition was treated successfully with 2 months of double-strength trimethoprim/sulfamethoxazole twice daily. He was also urged to leave his lesions untouched to allow them to resolve. His long-term prognosis is somewhat guarded.
Neurotic excoriations can present as polymorphic lesions of varying size and age. There is no consensus on the prevalence of neurotic excoriations. One study reports that 1.6% of a random sample of 2511 adults in the United States have skin picking with visible lesions.7 Another study reports that 5.4% of 354 patients have neurotic excoriations with impairment of daily functioning and psychosocial stress.8 This disease is more common in women, with a ratio of women to men of approximately 8:1; it tends to affect women aged between 20 and 50 years.9
The etiology is unknown. Research now focuses on abnormal brain activity found on magnetic resonance imaging. One study showed abnormally low brain activity in regions important to habit formation, action monitoring, and inhibition.10
Lesions commonly occur on the face, extensor surfaces, scalp, shoulders, and back—anywhere a patient can reach to scratch or cause excoriations.11 More recent lesions appear as angular excoriations that may or may not have a crust. Older lesions present as atrophic scars or hypertrophic nodules. Postinflammatory hypo- and hyperpigmentation is common. The appearance of lesions can also be affected by the tool, such as fingernails, teeth, scissors, or tweezers, used to scratch. The distribution of lesions is among the more important clues, as they only appear where the patient can reach. Some complications include ulceration, infection, scarring, and long-lasting disfigurement.
Neurotic excoriations are associated with numerous psychiatric disorders, including affective disorders, anxiety disorders, eating disorders, and substance abuse. It is also commonly seen in patients with Prader-Willi syndrome, a developmental disorder caused by loss of the paternal 15q11-13 gene. Most commonly, it is associated with depression, anxiety, and obsessive-compulsive disorder.12
Patients are typically aware that they have unavoidable urges to pick or scratch their skin where these lesions occur. These urges usually occur episodically and usually last for approximately 5 to 10 minutes; however, some patients may complain of pruritic urges lasting for hours. These urges cause a significant level of psychological distress that is only relieved through picking the skin.
Diagnostic criteria, according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition,13 includes recurrent skin picking and repeated attempts to decrease or stop skin picking. The act of picking causes significant distress or impairment in important areas of functioning. Skin picking cannot be attributed to other medical conditions, medication side effects, or substance abuse, and skin picking is not better explained by symptoms of another mental disorder.
The differential diagnosis includes atopic dermatitis, psoriasis, scabies, bullous pemphigoid, furunculosis, and chronic pruritus.
Management options are multifactorial. Psychiatric management is usually needed to help patients with their insight, awareness, and motivation. If a medical cause is suspected (polycythemia vera or uremia), goals should be aimed at focusing on the underlying disorder.
High-potency topical corticosteroid use has been found to reduce symptoms. Intralesional glucocorticoids also can be beneficial. Other options include laser treatment for scarring and phototherapy with narrow-band ultraviolet B rays to reduce pruritus.14 Semi-occlusive dressings can help to hinder skin picking, limiting further damage and promoting healing. Antibiotic use is beneficial to treat infected lesions or ulcerations and prevent bacterial colonization.
As is the case with many of these patients, the patient in our case was in denial regarding her role in the disorder and refused treatment with psychoactive medications and a referral to psychiatry. She was given a prescription for topical triamcinolone 0.1% cream for application twice daily and a 2-week course of cephalexin, 500 mg 3 times daily to reduce any bacterial colonization. Her family was counseled regarding the nature of the problem and its likely intractability.
Aaron Fong is a medical student and Rana Mays, MD, is a dermatology resident at Baylor College of Medicine in Houston.
- Pardos de la Gandara M, Raygoza Garay JA, Mwangi M, et al. Molecular types of methicillin-resistant Staphylococcus aureus and methicillin-sensitive S aureus strains causing skin and soft tissue infections and nasal colonization, identified in community health centers in New York City. J Clin Microbiol. 2015;53(8):2648-2658.
- Faden H, Lesse AJ, Trask J, et al. Importance of colonization site in the current epidemic of staphylococcal skin abscesses. Pediatrics. 2010;125(3):e618-e624.
- Uhlemann AC, Dordel J, Knox JR, et al. Molecular tracing of the emergence, diversification, and transmission of S aureus sequence type 8 in a New York community. Proc Natl Acad Sci U S A. 2014;111(18):6738-6743.
- Macente S, Helbel C, Souza SF, et al. Disseminated folliculitis by Mycobacterium fortuitum in an immunocompetent woman. An Bras Dermatol. 2013;88(1):102-104.
- Bahrain M, Vasiliades M, Wolff M, Younus F. Five cases of bacterial endocarditis after furunculosis and the ongoing saga of community-acquired methicillin-resistant Staphylococcus aureus infections. Scand J Infect Dis. 2006;38(8):702-707.
- Stevens DL, Bisno AL, Chambers HF, et al; Infectious Diseases Society of America. Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the Infectious Diseases Society of America. Clin Infect Dis. 2014;59(2):e10-e52.
- Keuthen NJ, Koran LM, Aboujaoude E, et al. The prevalence of pathologic skin picking in US adults. Compr Psychiatry. 2010;51(2):183-186.
- Hayes SL, Storch EA, Berlanga L. Skin picking behaviors: an examination of the prevalence and severity in a community sample. J Anxiety Disord. 2009;23(3):314-319.
- Wong JW, Nguyen TV, Koo JY. Primary psychiatric conditions: Dermatitis artefacta, trichotillomania and neurotic excoriations. Indian J Dermatol. 2013;58(1):44-48.
- Odlaug BL, Hampshire A, Chamberlain SR, Grant JE. Abnormal brain activation in excoriation (skin-picking) disorder: evidence from an executive planning fMRI study. Br J Psychiatry. 2016;208(2):168-174.
- Calikusu C, Kucukgoncu S, Tecer Ö, Bestepe E. Skin picking in turkish students: prevalence, characteristics, and gender differences. Behav Modif. 2012;36(1):49-66.
- Miller JL, Angulo M. An open-label pilot study of N-acetylcysteine for skin-picking in Prader-willi syndrome. Am J Med Genet A. 2014;164A(2):421-424.
- American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Washington, DC: American Psychiatric Association; 2013.
- Özden MG, Aydin F, Sentürk N, et al. Narrow-band ultraviolet B as a potential alternative treatment for resistant psychogenic excoriation: An open-label study. Photodermatol Photoimmunol Photomed. 2010;26(3):162-164.