PANCE (Physician Assistant National Certifying Exam) — All Questions
5 questions
A 22-year-old woman noticed a single 4-cm oval, pink, scaly patch on her trunk. Ten days later, many smaller oval lesions appeared on her back, aligned along skin cleavage lines in a Christmas tree pattern. Which diagnosis is most likely?
- a.Secondary syphilis
- b.Guttate psoriasis
- c.Tinea versicolor
- d.Pityriasis rosea✓
A herald patch followed by smaller oval lesions oriented along cleavage lines in a Christmas tree distribution is classic pityriasis rosea. Tinea versicolor causes hypo- or hyperpigmented macules with fine scale and no herald patch. Guttate psoriasis produces small drop-like plaques after streptococcal infection, and secondary syphilis classically involves the palms and soles; syphilis serology is still reasonable when the picture is atypical.
Nine days after starting a new anticonvulsant, a 40-year-old man develops fever, painful dusky macules with epidermal detachment over about 35% of his body surface area, and oral and conjunctival erosions. Besides admission to a burn or intensive care unit, which step is most important?
- a.Apply high-potency topical steroids
- b.Start empiric oral acyclovir
- c.Stop the suspected drug immediately✓
- d.Continue the drug and add an antihistamine
Epidermal detachment over more than 30% of body surface area with mucosal erosions after a new drug is toxic epidermal necrolysis; immediate withdrawal of the causative drug and intensive supportive care are the core of management. Continuing the drug worsens outcome. Acyclovir treats herpes infection, not a drug reaction, and topical steroids do not address a process that is detaching the epidermis.
A 30-year-old man has intense itching that is worst at night. Examination shows small papules and short linear burrows in the finger web spaces, on the wrists and along the waistline. His partner has similar symptoms. Which management is most appropriate?
- a.Oral cephalexin for him and his household contacts
- b.Topical permethrin for him and close contacts✓
- c.Oral terbinafine for him only
- d.Topical hydrocortisone for him only
Nocturnal itching with burrows in the web spaces, wrists and waistline and a symptomatic contact indicate scabies, treated with a topical scabicide such as permethrin with simultaneous treatment of close contacts to prevent reinfestation. Terbinafine treats dermatophytes, hydrocortisone only suppresses itch, and cephalexin treats bacterial skin infection rather than mite infestation.
A 68-year-old farmer has several rough, sandpaper-like, scaly pink papules on his forehead and the backs of his hands. Which statement best describes the significance of these lesions?
- a.Benign lesions needing no follow-up
- b.Lesions caused by papillomavirus infection
- c.Precursors of squamous cell carcinoma✓
- d.Early in situ lesions of malignant melanoma
Rough, scaly papules on chronically sun-exposed skin are actinic keratoses, premalignant lesions with a risk of progression to squamous cell carcinoma, so they are treated or monitored. They are not merely cosmetic, they are not a melanocytic precursor to melanoma, and they are caused by ultraviolet damage rather than papillomavirus.
An 80-year-old woman has several weeks of itching followed by large tense bullae on her trunk and flexural areas. Rubbing the skin next to a blister does not shear off the epidermis, and her oral mucosa is spared. Which diagnosis is most likely?
- a.Bullous impetigo
- b.Dermatitis herpetiformis
- c.Bullous pemphigoid✓
- d.Pemphigus vulgaris
Tense bullae in an older adult with a negative Nikolsky sign and little or no mucosal involvement characterize bullous pemphigoid, a subepidermal blistering disease. Pemphigus vulgaris produces flaccid, easily ruptured bullae with painful oral erosions and a positive Nikolsky sign. Dermatitis herpetiformis causes grouped itchy vesicles on extensor surfaces, and bullous impetigo is a localized staphylococcal infection.