DIRECTIONS: Choose the one best response to each question.
XII-1. A 34-year-old woman seeks evaluation for a skin lesion. On examination, the lesion is present on the extensor surface of the right elbow. It measures 2.4 cm in diameter and is raised, with a flat top and distinct edge. Overlying the lesion is an excess accumulation of stratum cornea. Further examination reveals several smaller lesions also located on extensor surfaces. Which term best characterizes the primary lesion for which the patient is seeking evaluation?
A. Macule with lichenification
B. Patch with a scale
C. Plaque with a crust
D. Plaque with a scale
XII-2. What term is used in dermatology to describe a coin-shaped lesion?
XII-3. A 5-year-old boy is brought in by his mother complaining of approximately 6 months of itching and scaling of the skin inside the elbows (see Figure XII-3). The area gets red occasionally and improves with over-the-counter topical steroid creams. There is no fever, chills, night sweats, or red streaks ascending the arm. The family has a pet cat and lives in a clean apartment. All of the following statements concerning this child are true EXCEPT:
FIGURE XII-3 (see Color Atlas) (Courtesy of Robert Swerlick, MD; with permission.)
A. Both of his parents likely have a history of atopic dermatitis.
B. He likely has a history of asthma or atopic rhinitis.
C. His serum IgE levels are elevated.
D. He has a greater than 70% chance of spontaneous resolution.
E. His lesions will likely respond to topical tacrolimus.
XII-4. A 63-year-old woman has a 5-year history of psoriasis involving her elbows that has been controlled with topical glucocorticoids and a vitamin D analogue. However, in the past 9–12 months she has developed worsening and new lesions involving her knees, gluteal regions, and scalp. She is increasingly uncomfortable and has noted swelling of her digits with pain and stiffness. She is up to date on all cancer screening and has no sign of systemic infection. Her physical examination is only notable for the psoriatic plaques that are red and scaling, and swollen, tender DIPs on both hands. All of the following therapies are indicated for worsening widespread systemic psoriatic disease EXCEPT:
XII-5. A 67-year-old man presents with complaints of diffuse rash with blistering. The lesions began as pruritic plaques distributed on the trunk and abdomen. Lesions are now appearing on the flexor surfaces of the arms. Some of the lesions have developed into tense blisters that rupture. As the lesions have healed, no scarring is present. A photo of the patient’s rash is shown in Figure XII-5. What would be the expected finding on biopsy of the lesion?
FIGURE XII-5 (see Color Atlas) (Courtesy of the Yale Resident’s Slide Collection; with permission.)
A. Cell surface deposition of IgG on keratinocytes
B. Cell surface deposition of IgG and C3 on keratinocytes
C. Granular deposits of IgA in dermal papillae
D. Linear band deposition of IgA in the epidermal basement membrane zone
E. Linear band deposition of IgG and/or C3 in the epidermal basement membrane zone
XII-6. A 24-year-old woman seeks evaluation for a rash that is present diffusely on her back, buttocks, elbows, and knees. The rash began abruptly and the patient is complaining of severe pruritus and burning associated with the rash. A biopsy of the rash demonstrates neutrophilic dermatitis within the dermal papillae, and immunofluorescence highlights granular deposition of IgA in the papillary dermis and along the epidermal basement membrane zone. What treatment do you recommend for this patient?
A. Dapsone 100 mg daily
B. Gluten-free diet
C. Prednisone 40 mg daily
D. A and B
E. All of the above
XII-7. A patient presents to you for evaluation of ear lesions worsening over the last 6–9 months. Each lesion began as a red papule with a thick adherent scale (see Figure XII-7). Since that time, they have progressed to the current pictured lesions with variable coloration, raised borders, and scars. There has been no improvement with use of topical glucocorticoids, which the patient borrowed from a friend. What is the best course of action for this patient at this time?
FIGURE XII-7 (see Color Atlas)
A. Aminoquinoline antimalarials
C. Systemic glucocorticoids
D. Vitamin E ointment
E. Wide surgical excision with regional lymph node dissection
XII-8. A 55-year-old man presents with fever and a blistering skin rash that has developed after taking allopurinol for gout. The patient also is complaining of a sore throat and painful watery eyes. On examination, the patient is found to have blisters developing over a targetoid lesion with oral mucosal involvement. The estimated body surface area that is currently affected is 33%. Which of the following statements regarding this patient’s diagnosis and treatment are TRUE?
A. Immediate treatment with intravenous immunoglobulin will decrease the extent of the disease and improve mortality.
B. Long-term treatment with glucocorticoids is required to prevent relapse of the disease.
C. The expected mortality rate from this syndrome is about 30%.
D. The most common drug to cause this syndrome is penicillin.
E. Younger individuals have a higher mortality than older individuals with this syndrome.
XII-9. A 32-year-old man receives amoxicillin/clavulanate for presumed bacterial sinusitis. One week later he presents with a diffuse itchy rash (see Figure XII-9). His mucous membranes are normal. Which of the following is the most likely diagnosis?
FIGURE XII-9 (see Color Atlas)
A. Morbilliform drug eruption
B. Pemphigus vulgaris
C. Stevens-Johnson syndrome
D. Toxic shock syndrome
XII-10. A 22-year-old woman comes to your office concerned about sun exposure. She brings a few sunblock creams into your office and wants to know which one is best for preventing wrinkling and blotchiness. She is less concerned about sunburn because she is trying to get a better tan. Blocking which ultraviolet rays will achieve her desired result?
C. Both UV-A and UV-B equally
D. Neither UV-A nor UV-B
XII-11. A 45-year-old patient with HIV/AIDS presents to the emergency department. He complains of a rash that has been slowly spreading up his right arm and is now evident on his chest and back. The rash consists of small nodules that have a reddish-blue appearance. Some of them are ulcerated, but there is minimal fluctuance or drainage. He is unsure when these began. He notes no foreign travel or unusual exposures. He is homeless and unemployed, but occasionally gets work as a day laborer doing landscaping and digging. A culture of a skin lesion grows a Mycobacterium in 5 days. Which of the following is the most likely organism?
A. M. abscessus
B. M. avium
C. M. kansasii
D. M. marinum
E. M. ulcerans
XII-12. A 22-year-old man presents to the emergency department complaining of generalized malaise and rash. The patient has a history of illicit drug use with intranasal heroin and cocaine. He admits to engaging in unprotected sexual intercourse with men in exchange for drugs. He was negative for the HIV virus 8 weeks previously. He has a prior history of syphilis and gonorrhea that were treated appropriately 2 years previously. Following treatment, his rapid plasma reagin test fell to a titer of 1:8 from a high of 1:128 after 12 months. On physical examination, the patient has normal vital signs without fever. He is well developed and has no wasting. Diffuse lymphadenopathy measuring up to 2.5 cm is palpable in the cervical, axillary, and femoral areas. Genital examination shows no ulcerations or lesions. The rash is shown in Figure XII-12. Which test is most likely to yield the appropriate diagnosis in this patient?
A. Fluorescent treponemal antibody test
B. HIV antibody
C. HIV viral load
D. Rapid plasma reagin test
E. Venereal Disease Research Laboratory test
FIGURE XII-12 (see Color Atlas) (Courtesy of Jill McKenzie and Christina Marra.)
XII-13. While on a medical mission to the Ivory Coast, you are asked to see a 17-year-old boy with a large skin lesion on his forearm (see Figure XII-13). The lesion began as a small bump about 3 weeks ago and has grown to the size of a raspberry. He has tender axillary adenopathy on the ipsilateral side but no other physical findings. His siblings report similar lesions that healed after about 6 months. Which of the following is the most appropriate therapy?
FIGURE XII-13 (see Color Atlas)
XII-14. Infection by what organism causes the rash shown in Figure XII-14?
FIGURE XII-14 (see Color Atlas) (Courtesy of Vijay K. Sikand, MD; with permission.)
A. Anaplasma phagocytophilum
B. Bartonella henselae
C. Borrelia burgdorferi
D. Ehrlichia chaffeensis
E. Rickettsia rickettsii
XII-15. A 36-year-old man with HIV/AIDS (CD4+ lymphocyte count = 112/μL) develops a scaly, waxy, yellowish, patchy, crusty, pruritic rash on and around his nose. The rest of his skin examination is normal. Which of the following is the most likely diagnosis?
A. Molluscum contagiosum
B. Kaposi’s sarcoma
D. Reactivation herpes zoster
E. Seborrheic dermatitis
XII-16. A 34-year-old man seeks the advice of his primary care physician because of an asymptomatic rash on his chest. There are coalescing light-brown to salmon-colored macules present on the chest. A scraping of the lesions is viewed after a wet preparation with 10% potassium hydroxide solution. There are both hyphal and spore forms present, giving the slide an appearance of “spaghetti and meatballs.” In addition, the lesions fluoresce to a yellow-green appearance under a Wood’s lamp. Tinea versicolor is diagnosed. Which of the following microorganisms is responsible for this skin infection?
A. Fusarium solani
B. Malassezia furfur
C. Penicillium marneffei
D. Sporothrix schenckii
E. Trichophyton rubrum
XII-17. A 19-year-old college freshman comes to the clinic complaining of blistering skin lesions on the back of his hands and arms that are painful. He’s noticed these occasionally during his childhood, and they were often precipitated by sunlight and healed with scarring. He now notices that since starting college they are more frequent, and often occur after drunken parties. His hands and forearms have numerous hypopigmented scars that he says are from previous episodes. The skin over the back of his hands appears thick and coarse. Otherwise his review of systems and physical examination is normal. The lesions on his hands are shown in Figure XII-17. Which of the following tests will most likely yield the correct diagnosis?
FIGURE XII-17 (see Color Atlas) (Courtesy of Dr. Karl E. Anderson; with permission.)
C. Plasma cortisol
D. Plasma porphyrin
E. Urine porphobilinogen
XII-18. A 22-year-old male comes to the clinic reporting severe penile itching and new skin lesions. His last sexual encounter was unprotected sex 3 weeks prior with a new female partner in her bed. He has not seen her since. Over the last 3 days he’s noticed new lesions on his penis and scrotum. The lesions are extremely pruritic, particularly at night and after a shower. His physical examination is shown in Figure XII-18. Which of the following is the best therapy?
A. Ceftriaxone plus azithromycin
C. Penicillin G
FIGURE XII-18 (see Color Atlas)