Furuncles along the bottom of the foot with associated superficial abscesses. 

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... can be used for acute paronychia to help relieve pain and encourage drainage. However, full treatment should employ antibiotics such as cephalexin or dicloxacillin as topical antibiotics have not been shown to be effective. 32 Some studies have shown that chronic paronychia is largely an inflammatory process with superimposed infection. Tosti et al. showed that chronic paronychia responded better to topical corticosteroids compared to oral antifungal medications. However, stan- dard treatment for chronic paronychia includes topical antifungal medication such as ketoconazole cream combined with a mild topical hydrocortisone to reduce inflammation. In cases where a large abscess is present, incision and debridement is often necessary. Pitted keratolysis, commonly known as sweaty sock syndrome, is a foot infection caused by gram-positive Corynebacterium species, in particular Kytococcus sedentarius. 1 Patients at increased risk are those with hyper- hydrosis who wear occlusive shoewear for long periods. Presentation is characterized by white skin discoloration with discrete cratered pits 1 to 4 mm in diameter on the weight bearing portions of the sole of the foot (Figure 4). 43 These pits are caused by skin degrading proteinases created by the infecting bacteria and become more severe with increased surrounding moisture. 30 Concurrent strong foot odor may result from sulfur compounds produced by bacteria. Mainstays of treatment include topical antibiotics such as erythromycin, mupirocin, and clindamycin applied twice daily. Benzoyl peroxide gel can alternatively be used in a once daily application. Prevention of pitted keratolysis focuses on moisture reducing shoes and socks and supple- mental application of aluminum chloride 20% to the soles of the feet. Verrucase vulgaris, better known as common warts, are contagious infections caused by various strains of the human papillomavirus (HPV), commonly types 2 and 4. There are multiple varieties of warts and over 100 types of HPV strains, but verruca plantaris specifically refers to warts on the weightbearing areas of the soles of the feet commonly caused by HPV types 1, 2, and 3. 24 Patients often present with lesions that are well demarcated with thickened, rough papules and plaques that are raised or flush with the level of surrounding skin (Figure 5). 24 Warts can often be confused with calluses and corns. Superficial sharp debridement of the lesions reveal punctate black dots that are thrombosed capillary vessels. 30 Warts on the plantar aspect of the foot can cause significant pain with standing and walking. In children, even without treatment, roughly 50% of warts disappear within 6 months and 90% are gone within 2 years. 24 However, warts are more persistent and severe in adults and immunosuppressed patients. Treatments vary widely and can be categorized as destructive, topical, intralesional, and oral. 19 , 24 Destructive therapies include cryotherapy with liquid nitrogen, local curettage, elec- trodessication, sharp excision, and pulsed-dye laser therapy. While surgical removal has been shown to be effective, there are associated complications including pain and wound healing. Topical treatments use salicyclic acid preparations, podophyllotoxin, retinoids, silver nitrate, and topical immunotherapeutic agents (squaric acid dibutyl ester). A Cochrane review found that topical treatments containing salicylic acid had the highest cure rate of 75% with no significant benefit of cryotherapy over salicylic acid. 17 The immunomodulating topical agent imiquimod has been shown to be effective without inducing pain that may interfere with ambulation. Intralesional therapy utilizes bleomycin and oral medication includes cimetidine. 43 HPV vaccines have not been shown to prevent the virus strain responsible for warts. Occlusion therapy with duct tape has not shown any significant treatment effect despite anecdotal reports. 47 During this treatment, a piece of duct tape is placed over the wart for a week, followed by soaking the wart in water and debriding with an emery board. Despite the various available treatments for warts, recurrence is very common even after complete removal. Preventing infections and re-infections requires protective shoewear as HPV can remain viable on surfaces of public areas and is transmitted through direct contact. Folliculitis is a superficial infection of the hair follicles that may occur anywhere on the skin. Bacterial folliculitis is characterized by a cluster of erythematous tender papules and pustules surrounding hair follicles, particularly in moist areas of the body prone to friction and perspiration such as the feet, groin, and axilla. 2 , 9 Lesions may be pruritic or painful in some cases with associated necrotic tissue. 39 The most commonly cited cause of folliculitis is infection with S. aureus. A furuncle, commonly known as a boil, is a painful form of folliculitis that can develop into a warm, erythematous, painful abscess (Figure 6). A carbuncle is a grouping of interconnected furuncles that can coalesce to form a deep, purulent mass with multiple fistulas. Abscesses are often tender and fluctuant with a raised central pustule surrounded by an erythematous ring. 39 Severe infections may present with active purulent drainage, fever, swollen lymph nodes, and fatigue. These lesions are contagious and can be mistaken for cystic acne, hidradenitis suppurativa, and epidermal cysts, and should be routinely cultured to rule out infection with methicillin-resistant S. aureus (MRSA). In recent years there has been a dramatic increase in the number of skin infections with MRSA (hospital-acquired and community-acquired), particularly among athletes, homeless persons, and intravenous drug users. 8 Risk factors include antibiotic use within the preceding year, poor hygiene, and compromised skin healing. In orthopaedic procedures, infection rates of S. aureus remain low, but methicillin resistance among these infections is high reaching nearly 50%. 16 MRSA has created significant complications in orthopaedic procedures necessitating further operative intervention and antimicrobial therapy. Infections with MRSA have a more aggressive appearance than common folliculitus and are characterized by erythematous lesions with a purulent center often with surrounding cellulitus. 23 Severe cases of MRSA infection may present with abscesses and systemic symptoms such as fever and malaise. Less common presentations of MRSA that require emergent treatment include bacteremia, septic arthritis, osteomyelitis, and necrotizing fasciitis. 14 , 25 Treatment with antibiotics should be guided by culture and sensitivity results of lesions. Local therapy for mild local- ized folliculitis includes warm water compress applications (10 minutes three times per day) and topical antibiotics such as clindamycin and mupirocin. 2 For large abscesses, incision and drainage is recommended with wound culture and postoperative antibiotics. 29 Aggressive folliculitis requires oral antibiotics including penicillins and cephalosporins, or azithromycin and moxifloxacin in patients with antibiotic allergies. 5 A recent trend to prophylactically address concerns of complicated MRSA infections has been the empiric use of oral ciprofloxacin, rifampin, trimethoprim- sulfamethoxazole (TMP-SMX), amoxicillin-clavulanic acid, or clindamycin while culture results are pending. 2 , 23 , 28 Infections resistant to oral therapy require intravenous antibiotics using vancomycin, daptomycin, gentamicin, or linezolid often combined with incision and debridement of necrotic tissue. 40 Patients with widespread infection are often colonized carriers of S. aureus through the nasal cavity or perineal region and are more prone to chronic, resistant infections. Chronic carriers require application of mupirocin ointment to affected colonized areas two times per day for one week or dilute bleach baths. 18 , 43 It is recommended that patients scheduled for elective operative intervention who have active draining lesions undergo antibiotic treatment and close monitoring for deep tissue spread prior to any surgery. 23 Young athletes in contact sports with folliculitis should be suspended from play until treated with oral antibiotics for 72 hours with absence of new lesions for at least 48 hours. 20 Prevention of folliculitis and its more severe sequelae is particularly challenging given the widespread prevalence of the bacteria and its increasing resistance to currently used antibiotics. Superficial infection of the skin and upper dermis is known as erysipelas while invasion further into the deeper dermis and subcutaneous fat constitutes cellultis. 29 Erysipelas presents as a well-defined, warm, expanding, erythematous plaque with associated fevers, chills, and fatigue (Figure 7). 6 Patients with erysipelas have the acute onset of symptoms within 48 hours of the initial infection and severe infections can be accompanied with vesicles, bullae, and petechiae with possible skin necrosis. The most common causative agent is Streptococcus pyogenes (beta-hemolytic group A Streptococci (GAS)) with the erythematous infection caused by an exotoxin. Erysipelas infection can enter through skin trauma, ulcers, and surgical incisions, but does not affect the subcutaneous tissue or release purulent material. 21 Predisposing risk factors in the foot include immune deficiency, diabetes, tinea pedis, abscess, and skin ulcerations. Erysipelas can be confused with contact dermatitis, angioedema, and cellulitis, and diagnosis is mainly through physical exam. Erysipelas can be differentiated from cellulitis by its raised advancing edges, demarcated borders, and depth of penetration and level of edema. Treatment requires oral or intravenous antibiotics including penicillins, clindamycin, or erythromycin, although skin may take weeks to return to baseline. 21 If left untreated, erysipelas can quickly spread to deeper tissue and ...