PANCE Exam: Dermatology Review Questions & Answers

ECZEMATOUS ERUPTIONS

Question: A 5-year-old girl presents with a 3 cm, hyperpigmented, scaling plaque located at the umbilicus. She also has smaller similar lesions on both ear lobes at the site of her ear piercings. Her mother states that this is extremely pruritic. What does this represent?
This reaction is consistent with an allergic contact dermatitis to nickel. Buttons, snaps, and other clothing closures all contain nickel. Costume jewelry also contains nickel. Nickel is a common sensitizing agent that causes an eczema-like reaction at sites of contact. Avoidance of metal is crucial in treatment and prevention. Occlusive techniques such as clear nail polish and duct tape provide minimal improvement. Avoidance and treatment with an appropriate topical steroid and oral antihistamine for itch relief is appropriate treatment.

Question: What is the appropriate treatment of contact dermatitis caused by poison ivy?
Wash all clothing that may have come into contact with the oils from the poison ivy plant. Topical treatment with a class I–III topical steroid is effective for limited or early lesions. Oral steroids are indicated for severe cases. Prednisone beginning at 60 mg (adults), tapering by 10 mg over a 2-week period. The pediatric dosing is 2 mg/kg PO qd as an initial dose, tapering over 2 weeks. Oral antihistamines such as Benadryl or hydroxyzine may provide relief from pruritus.

Question: A 17-year-old female patient has a rash on her elbows and knees. Upon examination, you find several well-demarcated erythematous plaques covered with silvery scales that exhibit pinpoint bleeding when removed. These lesions are located on her extensor surfaces. Examination of her nails reveals pitting. What is her diagnosis?
Psoriasis. This is a chronic disorder with bimodal peaks in incidence of 22.5 years and 55 years. Early onset is indicative of a more severe and long-lasting disease. There may be associated arthritis; otherwise, the disease is limited to the skin and nails. Remember: “Silvery scales and pitting nails.”

Question: A 13-year-old patient presents with erythema and yellow scaly plaques in his eyebrows, eyelids, and nasolabial folds. What is the most likely diagnosis?
This patient most likely has seborrheic dermatitis. Infantile and adolescent seborrheic dermatitis often improves with age. There is frequently a hereditary component. It occurs in areas where there is a concentration of sebaceous glands.

What are the diagnostic criteria for atopic dermatitis?
Essential clinical features include pruritus and eczematous changes in a predictable distribution. There is a specific distribution by age group. Infants may have involvement of the face and extension to the trunk, especially the extensor surfaces. Children from the age of 2 to puberty usually have involvement of the extremities, particularly the wrists, ankles, hands, feet, and popliteal and antecubital fossae. Beginning at puberty, the distribution changes to include the flexural creases, face, neck, and the dorsum of the hands and feet.
Supporting features of atopic dermatitis include early age of onset, family history of atopy, and xerosis.

Question: What is the treatment for atopic dermatitis?
Management of atopic dermatitis includes limiting bathing to 10 minutes daily with soap-free cleansers. In addition, liberal use of thick emollients especially right after bathing will help maintain skin hydration. Avoidance of irritant or allergens is also crucial to help control atopic dermatitis. Topical steroids are the first-line pharmacological treatment for atopic dermatitis. Pruritus can also be relieved with the use of oral antihistamines.

Question: A mother brings her 6-month-old daughter in for a diaper rash that has been unresponsive to over-the-counter diaper creams. On physical examination, you find a well-demarcated beefy red rash with pinpoint satellite papules. What is the most common causative organism?
Candida albicans commonly occurs in infants. The moist occlusive diaper provides an optimal environment for proliferation of this organism. Systemic antibiotics can also contribute to proliferation.

Question: Which chronic disorder with acute exacerbations is characterized by deep-seated vesicles located on the palms, soles, and lateral aspects of the fingers and intense pruritus?
Dyshidrotic eczema. Exacerbations are treated with moderate to potent topical steroids. Oral antihistamines help with pruritus.

Question: What is lichen simplex chronicus and how is it treated?
This is also called circumscribed neurodermatitis, which is a self-perpetuated skin disorder causing the skin to turn into dry, leathery, lichenified patches most commonly seen on the nape of the neck, wrists, forearms, and lower legs and perineal area. The best treatment for this disorder is to use flurandrenolide tape, which will prevent the patient from scratching while healing the dermatitis. Also, the use of oral antihistamines to relieve itching can be beneficial.


PAPULOSQUAMOUS DISEASES

Question: What type of reaction is erythema multiforme and what are its common causes?
Erythema multiforme is a hypersensitivity reaction. There are numerous possible inciting agents. Some of the most common are:
- infection, especially herpes simplex, Mycoplasma
- drugs such as sulfonamides, NSAIDS, phenytoin, barbiturates, and salicylates
- malignancy
- idiopathic

What is the most common location of erythema nodosum?
The most common site for erythema nodosum is the shin. These can also be found on the knees and extensor surfaces of the forearms. Skin findings are deep-red tender nodules. Erythema nodosum is a hypersensitivity reaction to a variety of stimuli and its causes include infectious organisms, drugs, malignancies, and connective tissue diseases. Often the cause is idiopathic.

Question: What is the Koebner phenomenon?
The development of plaques/lesions in areas where trauma has occurred. Just a scratch can trigger the development of a plaque. This is common in numerous conditions such as psoriasis, lichen planus, molluscum contagiosum, and verrucae.

Question: A 17-year-old male patient complains of spreading spots. They began several months ago on his upper back and have spread to involve the upper chest and upper arms. There are no associated symptoms; he is just concerned that he is becoming “spotted.” On physical examination, you see small, circular, tan macules with fine scaling. What is the presumptive diagnosis and how would you confirm your diagnosis?
This patient most likely has tinea versicolor, which is caused by the lipophilic yeast Malassezia furfur. This infection is most common during adolescence and early adulthood when sebaceous gland activity is at its peak. The easiest way to confirm the diagnosis is to perform a KOH Prep with 10% to 20% KOH. Visualization of hyphae (usually shortened) and spores is confirmatory; this is the classic “spaghetti and meatball” appearance.

Question: What are the treatment alternatives and appropriate patient education for the above patient?
Treatment options include antifungal shampoo such as selenium sulfide or ketoconazole 2% left on for 10 minutes before washing. This can be done daily for up to 2 weeks. Topical imidazoles such as ketoconazole, econazole, and oxiconazole can be applied twice daily for 2 weeks. For severe, recurrent or intractable cases PO ketoconazole 400 mg can be used.

Question: Urticaria that results within seconds of firm stroking of the skin is:
Dermatographism. This is a very common physical urticaria. Pressure urticaria, swelling resulting from local pressure, is a variant of dermatographism.

Question: A 20-year-old female patient complains of a spreading rash. She states it started with a dry scaling patch on the abdomen that was larger than the current lesions. Now she has smaller dry scaling patches located on her chest and pack. She denies any associated symptoms. What is the presumptive diagnosis?
The characteristic rash of pityriasis rosea begins with a “herald patch,” which is usually 2 to 5 cm. Within a week or two, smaller lesions distributed over the torso and proximal extremities develop along the cleavage lines (“Christmas tree” distribution). These are scattered scaling patches that may be asymptomatic or mildly pruritic. Treatment is symptomatic since this resolves spontaneously in 6 to 12 weeks. Oral antihistamines help with pruritus.

Question: What rash is classically associated with a “herald patch”?
Pityriasis rosea. Most cases begin with a single large, oval patch (herald patch). Then, there is a secondary eruption of small oval patches with a collarette of scale appear on the trunk parallel to the lines of cleavage, the “Christmas tree” distribution. A history of mild pharyngitis and malaise may precede the rash.

A 14-year-old adolescent presents to the emergency department with 103.1°F fever and dysphagia. He appeared ill and had small vesicles on the nasal and oral mucosa. An erythematous rash on his chest coalesced on the trunk with many small vesicles, some forming bullae. Vesicles were also present on the penis and scrotum. What is the likely diagnosis?
Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) are considered to be variants of the same disorder. SJS was formerly referred to as erythema multiforme major. Patients may initially present with SJS and evolve into TEN depending on the degree of epidermal detachment. Features of each include targetoid lesions that can develop into bullae with prominent mucosal involvement. Sometimes the bullae may become confluent and detach leaving a denuded base. SJS is diagnosed when there is less than 10% epidermal detachment, SJS–TEN is diagnosed with 10 % to 30% epidermal detachment, and TEN when there is greater than 30% detachment.

Question: A 25-year-old male patient presents with a well-defined oval violaceous lesion located in the groin. He states that it is pruritic and occurred approximately an hour after taking acetaminophen for a headache. He states this has happened before under similar circumstances. What is the likely diagnosis?
Fixed drug eruption. Common inciting agents in fixed drug eruptions are antimicrobial agents, tetracyclines, metronidazole, anti-inflammatory agents, oral contraceptives, phenolphthalein, and yellow food coloring. The eruptions usually appear within 30 minutes to 8 hours after ingesting the offending agent. The lesions are well defined, usually round or oval, and dusky red to violaceous macules. Thes may become edematous with erosions or bullae.

Question: What drugs are most often implicated in toxic epidermal necrolysis (TEN)?
Sulfonamides, penicillins, anticonvulsants, allopurinol, sulfonylureas, barbiturates, and NSAIDs.

Question: What is Nikolsky sign?
A positive Nikolsky sign is when the gentle pressure on the skin causes the epidermis to separate and leave a raw, denuded base.

Question: A 77-year-old man presents to your clinic complaining of multiple fluid-filled blisters to the flexor surfaces of his forearms. He states that he has had itching to these areas for quite sometime but now this has occurred. On examination, you see multiple tense bullae to the flexor surfaces of the arms with an irritated erythematous base. What is the most likely diagnosis?
Bullous pemphigoid. These are lesions that will have a life span of up to 5 to 6 years. The diagnosis is made by biopsy and immunofluorescence and treated with ultrapotent steroids.


ACNEIFORM LESIONS

Question: What are the typical clinical manifestations of hidradenitis suppurativa?
Typical skin lesions include open comedones, particularly the double comedones, and tender abscesses that may drain purulent or seropurulent material. Sinus tracts may also form. These lesions are most common in the axillae, anogenital region, and under the breast.

Question: What is the best treatment for the comedonal lesions (white heads and black heads) of acne vulgaris?
Topical retinoids are the treatment of choice for comedonal acne. Topical benzoyl peroxide and salicylic acid preparations have a mild comedolytic effect.

What are the side effects of tetracycline antibiotics commonly used to treat inflammatory acne?
Side effects include dental staining in children younger than 9 years, GI upset, photosensitivity, pseudotumor cerebri, and vulvovaginal candidiasis. Minocycline has the added side effects of blue-gray skin pigmentation of the skin or mucosa, lupus-like reactions, and vertigo.

Question: Describe the clinical manifestation of acne rosacea:
Early manifestations include facial flushing in response to heat, spicy foods, alcohol, warm drinks, and sun exposure. Tiny papules and pustules may also be present early. Later manifestations can include telangiectasias, sebaceous hyperplasia, and rhinophyma. Ocular symptoms, such as blepharitis, conjunctivitis, and episcleritis, may occur. Distribution is primarily on bilateral cheeks. There are no comedones present.

Question: Describe the different forms of folliculitis:
Folliculitis depends on the source of the infection. The most common cause is staphylococcal bacteria and is more common in diabetic patients. Other causes include “hot tub” folliculitis, which is caused by Pseudomonas and produces follicular pustules, and nonbacterial folliculitis, which can be caused by friction and oils.


INSECTS/PARASITES

Question: A 12-year-old female patient complains of intense generalized itching; it worsens at night. On physical examination, she has erythematous papules on her hands and feet including the palms or soles. She also has papules and nodules around the umbilicus and in the genital area. Close examination reveals a linear lesion in the webspace on her hands. What is the presumptive diagnosis and how would you confirm your suspicion?
Scabies. Scabies are due to the mite Sarcoptes scabiei var. hominis. To confirm your diagnosis, an intact burrow or papule should be scraped and the scraping should be placed on a glass slide with mineral oil. Visualization of a mite, eggs, or feces is diagnostic for scabies.

Question: What is the appropriate treatment for the patient described in the previous question?
Appropriate treatment is application of 5% permethrin cream applied from the neck to toes and left on overnight (8 hours) and then washed off. All people who live in the same residence should be treated at the same time. After treatment, carpets and upholstered furniture should be vacuumed and sheets and clothing should be washed in hot soapy water. This treatment should be repeated in 1 week to kill any mites that have hatched in the interim. Oral antihistamines can be prescribed to ameliorate pruritus. Very frequently, the patient has a postscabetic dermatitis that can be treated with appropriate topical steroids.

Question: What is the drug of choice for pediculosis capitis (head lice)?
1% permethrin (which is available OTC).

Question: What is the treatment of choice for scabies and how should it be used?
5% permethrin cream applied overnight to all skin surfaces from the neck down. Special attention should be given to webspaces and skin under the nails. Treatment should be repeated in 1 week.

Question: What are two potential skin manifestations that can be caused by a brown recluse spider?
Local pain and cellulitis, which can progress to an area of necrosis that spreads.


NEOPLASMS

Question: A 62-year-old male tennis player with androgenetic alopecia presents with small scattered areas of skin-colored hyperkeratotic scale. When scraped, they are tender. The texture is that of sandpaper when palpated. What does this most likely represent?
This presentation is consistent with actinic keratosis. These are more common in middle-aged men, especially those who spend a great deal of time outdoors. These lesions are often easier to feel than to see. AKs are isolated or scattered discrete lesions distributed in sun-exposed areas. They can progress to squamous cell carcinoma.

Question: Brown plaques with a warty “stuck on” appearance that erupt after the age of 30 and that have no malignant potential are consistent with:
Seborrheic keratosis.

Question: A 50-year-old man present with two pearly papules: one on the nostril and another on the nasolabial fold. These papules are smooth and dome shaped with some overlying telangiectasias. Your patient states that these have been growing slowly. What do these papules most likely represent?
Basal cell carcinoma (BCC) is the most common cutaneous malignancy. These lesions most likely represent the most common variant of BCC, nodular basal cell carcinoma. The papules may also display a raised, rolled border and may be red or skin colored. Later stages may also display central ulceration, bleeding, and crusting. Other types of BCC include ulcerating BCC, sclerosing BCC, superficial multicentric BCC, and pigmented BCC.

Question: Nevi should be examined for what characteristics when evaluating for atypia?
Asymmetry: one-half is unlike the other half
Border irregularity: irregular, scalloped, or poorly defined borders
Color variation: variations in color present (tan, brown, black, white, red)
Diameter: >6 mm in acquired after the age of 1 year
Evolution: mole that looks different than the rest or is changing

Question: What are the risk factors for melanoma?
- Fair complexion
- History of sunburns
- More than 50 moles
- Atypical moles
- Family history of melanoma

Question: A periungual extension of brown-black pigmentation from longitudinal melanonychia onto the proximal nail fold is an indicator of?
This is consistent with a Hutchinson sign, which is an indicator of subungual melanoma. However, it is not pathognomonic. Diagnosis is made histologically.

Question: What are the most common locations of melanomas in African Americans? In Caucasian Americans?
African Americans: palms, soles, nails, and mucous membranes
Caucasian Americans: back and lower legs

Question: What are the clinical characteristics of dysplastic nevi?
They may be large (>6 mm), have variations of color, be asymmetric, and/or have irregular borders.


HAIR AND NAILS

A patient presents with the complaint of losing her hair. On physical examination, you note that there is a smooth patch of loss of hair and also note the presence of small “exclamation hairs.” What is the likely diagnosis?
Alopecia areata. The patient could develop more extensive patches that will extend to the entire scalp or body. In some cases, this may be associated with Hashimoto thyroiditis, Addison disease, pernicious anemia, and vitiligo.

Question: How is onychomycosis diagnosed and what is the appropriate treatment?
Clinical diagnosis must be confirmed by laboratory examination. The preferred method of confirmation can be achieved by isolation of fungus on culture medium. Fungal culture allows for confirmation of the species of fungus. KOH examination of subungual debris or nail plate can be used to confirm the presence of hyphae.
Approved treatment regimens are
- Terbinafine 250 mg/day for 6 weeks (fingernails) and 12 weeks (toenails)
- Itraconazole 200 mg/day for 6 weeks (fingernails) and 12 weeks (toenails)
Patients should be advised that nails do not appear completely normal after treatment due to slow growth of the nails. However, new growth should appear as normal.

Question: A patient presents with red, tender, and indurated lateral nailfold with purulent drainage on his ring finger. What is the diagnosis?
Paronychia is inflammation surrounding the nail. Acute paronychia is painful, erythematous, and frequently has purulent drainage. The common causative organism is Staphylococcus aureus; however, bacterial cultures should be performed to confirm and rule out resistant organisms.

Question: What are Beau lines?
Transverse grooves in the nailbed. Single nail involvement usually indicates a traumatic inciting event. Multiple nail involvement usually indicates trauma, dermatologic disorder, or systemic illness.

Question: A 6-year-old African American boy presents with diffuse patchy scaling in the scalp with areas of black dot alopecia. What is the presumptive diagnosis and how is it treated?
Tinea capitis is extremely common in school-aged children especially those from the inner city. There is usually posterior cervical lymphadenopathy associated with this infection. Diagnosis is confirmed with a fungal culture. Only 10% of tinea fluoresces with Wood lamp examination making it less than useful in diagnosing. The gold standard for treatment is griseofulvin (15 mg/kg/day for 6–8 weeks) and an antifungal shampoo (ketoconazole 2% or selenium sulfide 2.5%) two to three times a week. The shampoo should be allowed to sit on the scalp for 10 minutes before washing out.


VIRAL DISORDERS

Question: Describe the treatment options for a woman with condyloma acuminatum:
Genital warts can be treated with a couple of therapies. Podophyllin resin in tincture of benzoin is commonly used. Other therapies include cryotherapy, CO2 laser therapy, podofilox, or imiquimod cream.

A 5-year-old child develops a rash that starts on the face and quickly spreads to the trunk. The lesions begin as small vesicles on a red base. After a couple of days the lesions crust over, but new ones are still forming. This is the characteristic rash of:
Chicken pox, varicella zoster virus, is transmitted by airborne droplets and is highly contagious. Patients are contagious 48 hours before the characteristic rash appears. This continues until all lesions are crusted over. Chicken pox used to be a common childhood illness until the vaccination became routine.

Question: A 4-year-old boy who recently had a few days of bright red cheeks now has a lacy appearing rash on both upper extremities. There are no associated symptoms. What is the most likely cause?
This represents erythema infectiosum or fifth disease. The causative organism is Parvovirus B19.
This viral exanthem has three overlapping phases. First is the “slapped cheek” phase, which is characterized by fiery red facial erythema. The second phase is the exanthem, which affects the trunk and extremities. It is characterized by a lacy or reticulated rash. Third is the recurrent phase, which usually fades but recurs on exposure to sunlight and warmth or with physical exercise.

Question: A mother brings her 14-year-old boy to you a week after you prescribed ampicillin for his pharyngitis. Mom says he developed a rash over his torso, arms, legs, and even the palms of his hands. Upon examination, the patient has an erythematous, macular, and papular rash. What might the adolescent have other than pharyngitis?
Infectious mononucleosis. In almost 95% of patients with Epstein–Barr viruses that are treated with ampicillin, a rash will develop. The rash and subsequent desquamation will last about a week.

Question: A 72-year-old woman has a painful red rash with vesicles on erythematous bases in a bandlike distribution on the right side of her lower back, which spreads down and out toward her hip. What is your diagnosis?
Shingles or herpes zoster disease. This is due to the reactivation of a dormant varicella zoster virus in the sensory root ganglia of a patient with a history of chicken pox. The rash is in the distribution of the dermatome, in this case L5. It is most common in those older than 50 years or in patients who are immunocompromised.

Question: A patient with shingles extending to the tip of his nose is at risk for what?
Vesicles at the tip of the nose is Hutchinson sign. This indicates that the varicella zoster virus resides in the nasociliary branch of the ophthalmic nerve. Complications include ocular inflammation and corneal denervation. This is a medical emergency and needs immediate referral.

Question: What is the causative organism of verruca vulgaris and what are its appropriate treatment options?
Verruca vulgaris is caused by the human papilloma virus (HPV). Treatment options range from watchful waiting, OTC salicylic acid preparations, manual paring, cryotherapy, topical imiquimod cream, and injection therapy with candida antigens. Pulsed dye laser has also been useful but can cause scarring.

Question: An otherwise healthy 8-month-old female infant runs a high fever (105°F). Just as the fever subsides, a rash of pale pink oval macules appear on the trunk. These quickly become confluent. Within 48 hours, the rash subsides. What is the most likely diagnosis?
Roseola (exanthem subitum) is a viral disorder that affects children between the ages of 6 months and 4 years. The causative organism is HHV-6 and HHV-7. The prodrome is a high fever between 104 and 106°F in an otherwise well child. Just as the fever subsides, the rash appears. The rash consists of numerous pale pink oval macules on the trunk and neck that become confluent. Within 48 hours, the rash subsides without scaling or peeling.

A patient with AIDS presents with a grayish-white “corduroy-like” plaque on the lateral borders of her tongue that does not scrape off. What is the presumptive diagnosis?
Oral hairy leukoplakia, which is caused by EBV infection of the oropharynx.

Question: What are the goals of management of herpes zoster?
Reduce viral shedding, promote healing of lesions, prevent secondary infection, minimize pain, and prevent or minimize postherpetic neuralgia.

Question: What are Koplik spots and with which viral exanthem are they associated?
Koplik spots are gray-white papules on the buccal mucosa. They are pathognomonic for rubeola (measles). Other symptoms of rubeola include the three Cs: cough, coryza, and conjunctivitis.


BACTERIAL INFECTIONS

Question: What is a carbuncle?
A carbuncle consists of multiple deep loculated dermal and subcutaneous abscesses. There may be multiple openings that drain pus. They are extremely painful. Carbuncles occur mainly in hair-bearing areas and sites of friction and sweating. Risk factors for development include obesity, immunosuppression, hyper-IgE, chronic granulomatous disease, and malnutrition.

Question: Differentiate between ecthyma and impetigo:
Impetigo is a superficial bacterial infection of the skin most commonly caused by S. aureus or group A Streptococcus. Classic skin findings include small erosions and golden-yellow crusting. Common distribution is on the nose and lip or as secondary infection of various dermatoses. Ecthyma is a deep erosion or ulcer with a thick crust most commonly caused by S. aureus or group A Streptococcus. Lesions are more common on distal extremities.

Question: Differentiate between erysipelas and cellulitis:
Erysipelas and cellulitis are both red, hot, tender areas of skin. Erysipelas, however, is well demarcated, with sharp, raised advancing borders and is more superficial and commonly has lymphatic involvement. Cellulitis has more indiscreet margins and no lymph involvement. The most common pathogen of both the disorders is Group A Streptococcus.

Question: A mother brings her 4-year-old girl to you because she has a terrible rash. The child’s face has patches of shallow erosions covered in a thick, honey-colored crust. Just 2 days ago, these lesions were small red papules. What is your diagnosis?
Impetigo. This is most common in children and usually occurs on exposed areas of skin. Most limited cases can be treated with topical mupirocin antibiotic ointment. However, extensive disease should be treated with systemic antibiotics. For staphylococcal, use dicloxacillin, cephalexin, or amoxicillin plus clavulanic acid. For streptococcal, use Benzathine penicillin, penicillin V, or cephalexin. For penicillin-allergic patients, use erythromycin, clarithromycin, or azithromycin.

Question: Which organism is probably responsible for the infection described in the previous question?
Most impetigo cases are caused by Staphylococcus aureus. β-Hemolytic Streptococcus is the second most common infecting agent. It can also be coinfecting with Staphylococcus aureus.

What is the appropriate treatment for a cyst/abscess that occurs just above the gluteal fold in the sacrococcygeal region?
Appropriate treatment for a pilonidal cyst is incision and drainage (I&D) of the cyst. The incision should extend to the subcutaneous tissue with removal of all hair and debris. The wound should be packed. No antibiotics are necessary unless there is an associated cellulitis. Follow-up with a surgeon shortly after I&D is recommended since the recurrence rate is high.

Question: What age group does staphylococcal scalded skin syndrome (SSSS) usually affect?
SSSS most often occurs in neonates and young children (<5 years).

Question: What is the treatment for SSSS?
Oral or IV penicillinase-resistant penicillin, first- or second-generation cephalosporins, or clindamycin are appropriate. Modification may be made after sensitivities are determined. In patients with severe infection, hospitalization is required often times in burn units with special attention given to fluid and electrolyte management, pain management, and infection control.

Question: A 2-year-old girl has significant perianal erythema and small discrete red papules in the gluteal area. She has also been constipated because she is withholding her bowel movements due to pain. What is the presumptive diagnosis?
Perianal staphylococcal/streptococcal infection. The diagnosis can be confirmed with a bacterial culture. This usually responds well to topical mupirocin ointment. Oral penicillin V (or erythromycin in allergic patients) can also be used.

Question: What is the inciting event for the development of decubitus ulcers?
Decubitus ulcers result from ischemia caused by prolonged exposure to pressure.

Question: Describe the presentation of SSSS:
It is most common in children younger than 5 years of age, particularly in those younger than 3 years. It may begin as a conjunctivitis, or local infection of nares, mouth, or umbilicus; but often no clinical infection is apparent. Initially, the lesions consist of diffuse ill-defined erythema or a scarlatiniform rash. This quickly progresses to with deepening erythema and the onset of tenderness. Bullae may be present especially in infants. Within 24 to 48 hours, the lesions become more widespread. Later, the skin peels off with gentle pressure (Nikolsky sign). During the healing phase, desquamation occurs. Because SSSS does not have mucosal involvement, it can be differentiated from TEN.


OTHER DERMATOLOGIC DISORDERS

Question: Upon routine examination, a 76-year-old female patient is found to have thickening and brown hyperpigmentation of the skin on the neck and axillae. This finding can be a marker for what disorders?
Acanthosis nigricans is most commonly associated with obesity and insulin resistance. However, endocrine disorders, drug administration, and malignancy should also be considered. It is the velvety brown hyperpigmentation and thickening of intertriginous areas. It is most common around the neck and in the axillae. Overweight and obese patients should be worked up for insulin resistance. However, acanthosis nigricans can also be associated with malignancy, particularly of the gastrointestinal and genitourinary systems.

A port-wine stain (PWS) in the distribution of the first branch of the trigeminal nerve (V1) is characteristic of what disorder?
Sturge-Weber syndrome (SWS) is a neuroectodermal disorder with a characteristic PWS in a V1 distribution. Other branches of the trigeminal nerve (V2 and V3) can also be involved. There is also a central nervous system (CNS) component of SWS. The most common CNS manifestation is seizures. Glaucoma is also a frequent manifestation of SWS. It may be present at birth or any time before the fourth decade.

Question: Transient erythematous well-circumscribed wheals that are intensely pruritic are characteristic of:
Urticaria; these are representative of a type I hypersensitivity reaction.

Question: Xanthomas are associated with which metabolic disorder?
Familial hyperlipidemia. Xanthomas are yellow-brown or orange plaques, papules, or infiltrations in tendons. They are most common on the extensor surfaces of the extremities. Eruptive xanthomas are most common on the buttocks, elbows, or knees.

Question: A 5-year-old African American boy presents with a sharply demarcated annular macule with complete loss of pigment on his right knee. He also has a well-defined hypopigmented macule located on his right temporal area. There is no scaling or erythema noted. What disorder does this most likely represent?
This patient most likely has vitiligo. Vitiligo is thought to be an autoimmune disorder that affects melanocytes. There may be areas of involvement in differing stages with a range of macules slightly lighter than normal pigmentation to complete loss of pigment.

Question: What examination technique is helpful in identifying vitiligo lesions in lighter skin types and in sun-protected areas where contrast may not be as obvious?
Wood lamp examination in a completely darkened room without windows will show accentuation of vitiligo lesions.

Question: A patient presents with a red pedunculated papule that has a collarette of scale. She states that it appeared less than a week ago and has been growing rapidly. She reports that it bleeds profusely in response to minor trauma. What is the probable diagnosis and treatment?
This most likely represents a pyogenic granuloma. This is an acquired vascular lesion that often forms in response to trauma, such as an insect bite or scratch. Treatment for pyogenic granuloma includes shave excision followed by electrodessication to achieve hemostasis and prevent reoccurrence.

Question: What are the diagnostic criteria for Kawasaki disease?
Fever for 5 days or more with at least four of the following:
- Bilateral injected conjunctiva
- Red fissured crusted lips, hyperemia of oropharynx, and red strawberry tongue
- Erythema and/or edema of the extremities
- Skin manifestations (diffuse macular and papular, erythematous eruption, diffuse urticarial rash, or scarlet fever-like rash)
- Cervical lymphadenopathy

What is the treatment for Kawasaki disease?
Treatment is directed toward reducing inflammation and preventing damage to the arterial wall. Standard treatment regimen includes intravenous immunoglobulin (IVIG) and aspirin. Rapid diagnosis is crucial because treatment should be started within the first 10 days of the illness.

Question: A 6-year-old boy presents with palpable purpura on bilateral lower extremities. He also complains of pain and mild swelling in his ankles and knees. Today, he is experiencing some abdominal discomfort as well. He is recuperating from streptococcal pharyngitis. What is his most likely diagnosis?
Henoch-Schönlein purpura (HSP) is a vasculitic disorder that primarily affects children between the ages of 2 and 11 years. Classic presentation includes palpable purpura in dependent areas, arthritis, abdominal pain, and glomerulonephritis. There are many possible etiologies including group A β-hemolytic streptococci, viruses, immunizations, and drugs.

Question: What are the diagnostic criteria for neurofibromatosis type 1 (NF1)?
Café-au-lait macules: six or more measuring ≥0.5 cm before puberty (≥1.5 cm in adults)
Axillary and/or inguinal freckling
Fibroma: 2+ dermal neurofibromas
Eye: 2+ Lisch nodules
Skeletal dysplasia
Pedigree: first-degree relative with NF1
Optic
Tumors: optic nerve glioma

Question: Small, follicular-based, hyperkeratotic papules located on the outer aspects of the upper arms and thighs are consistent with what chronic condition?
Keratosis pilaris is a chronic disorder seen in early childhood through adulthood. Usually there is improvement as the patient progresses into adulthood. Treatment consists of keratolytic agents, which may help smooth the affected skin.

Question: What side effects are associated with topical corticosteroids?
Atrophy, striae, telangiectasia, erythema, and hypopigmentation of the skin are common side effects. Topical corticosteroids used on the eyelid can cause cataracts and glaucoma. Systemic side effects include hypothalamic-pituitary-adrenal axis suppression.

Question: A 5-year-old boy presents with small discrete erythematous papules in a perioral and nasolabial distribution. What is the diagnosis and proper treatment?
This is consistent with perioral dermatitis. The etiology is unknown. Proper treatment is with topical antibiotics such as erythromycin, clindamycin, and metronidazole. In more severe cases, oral erythromycin or tetracyclines (in patients older than 8 years) are required. Recurrence is common.

Question: What is the reaction when perioral dermatitis is treated with a topical steroid?
A granulomatous perioral dermatitis results from treatment with a topical steroid. The patient must be weaned off of the topical steroid and treated with an appropriate topical antibiotic to prevent a rebound flare.

Name some of the more common etiologies that produce exanthems:
The morbilliform exanthems can be caused by drugs as well as viral infections such as rubeola, rubella, erythema infectiosa, Epstein Barr, Coxsackie virus, HIV, and adenovirus. Bacterial forms can be caused by typhoid, rickettsia, syphilis, and meningococcemia. The scarlatina forms can be caused by scarlet fever, toxic shock, and Kawasaki disease.

Question: An 89-year-old bedridden nursing home patient is found to have a superficial ulceration involving only the epidermis located in the sacral region. What is the presumptive diagnosis?
This most likely represents a stage II decubitus ulcer. Common sites for decubitus ulcers are the hip and buttock regions. Decubitus ulcers are classified in stages:
Stage I: intact skin with blanchable erythema
Stage II: partial thickness skin loss, involves epidermis and possibly the dermis
Stage III: full thickness skin loss involves subcutaneous tissue up to fascia
Stage IV: full thickness skin loss with damage to muscle, bone, tendon, or joint


REFERENCES
Paller AS, Mancinic AJ. Hurwitz Clinical Pediatric Dermatology: A Textbook of Skin Disorders of Childhood and Adolescence. 3rd ed. Elsevier Saunders; 2006.
Habif TP, Campbell JL, Chapman MS, Dinulos JG, Zug KA. Skin Disease: Diagnosis and Treatment. 2nd ed. Philadelphia, PA: Elsevier Mosby; 2005.
Wolff K, Johnson RA. Fitzpatrick’s Color Atlas and Synopsis of Clinical Dermatology. 6th ed. New York, NY: McGraw-Hill; 2009.
Pryor JP, Todd B, Dryer M. Clinician’s Guide to Surgical Care. Lange Series. New York, NY: McGraw-Hill; 2008.