A 65-year-old man comes to the office due to a skin condition. For the last 6 years, the patient has had slowly progressive, patchy depigmentation involving the face, posterior scalp, hands, genital area, and feet. There is no associated itching, pain, or scaling. Medical history is notable for hypertension, stable coronary artery disease, rheumatoid arthritis, and benign prostatic hyperplasia. The patient quit smoking 20 years ago and does not use alcohol or illicit drugs. Temperature is 36.9 C (98.4 F), blood pressure is 136/88 mm Hg, and pulse is 76/min. Skin examination shows widespread areas of depigmentation as shown below. Physical examination is otherwise unremarkable. Which of the following best explains the pathology of this patient's condition?

Question

A 65-year-old man comes to the office due to a skin condition.  For the last 6 years, the patient has had slowly progressive, patchy depigmentation involving the face, posterior scalp, hands, genital area, and feet.  There is no associated itching, pain, or scaling.  Medical history is notable for hypertension, stable coronary artery disease, rheumatoid arthritis, and benign prostatic hyperplasia.  The patient quit smoking 20 years ago and does not use alcohol or illicit drugs.  Temperature is 36.9 C (98.4 F), blood pressure is 136/88 mm Hg, and pulse is 76/min.  Skin examination shows widespread areas of depigmentation as shown below.  Physical examination is otherwise unremarkable.  Which of the following best explains the pathology of this patient's condition?

Quizplus · Accepted Answer

11ec25c8_d394_bd79_bc81_3dd2bbdb7051_MD0003_00 This patient has well-demarcated depigmented macules consistent with vitiligo. Vitiligo is caused by regional destruction of melanocytes, most likely due to an autoimmune etiology. Genetic and environmental factors may also play a role. It can occur as an isolated disorder but is often associated with other autoimmune conditions (eg, autoimmune thyroid disease, rheumatoid arthritis, pernicious anemia, primary adrenal insufficiency). The course is highly variable, although the condition is usually slowly progressive. The diagnosis of vitiligo is usually made on clinical grounds. Biopsy can be considered in uncertain cases and will show loss of melanocytes, often with scattered lymphocytes at the lesion border. When treatment is desired, topical or systemic corticosteroids are the most common first-line intervention. (Choices A, D, E, and F) Idiopathic guttate hypomelanosis is a common finding with aging and is characterized by small macules in sun-exposed areas. Infection with Mycobacterium leprae causes leprosy, characterized by areas of hypopigmentation with anesthesia. Tinea versicolor presents with lightly scaled macules, primarily at the chest and upper back. Post-inflammatory hypopigmentation is characterized by patchy involvement in areas of prior trauma or inflammation. The lesions in these disorders are hypopigmented rather than completely depigmented, as in vitiligo. Idiopathic guttate hypomelanosis Tinea versicolor (Choice C) Piebaldism is an autosomal dominant disorder characterized by patchy absence of melanocytes. It is usually noticed at birth and is confined to the head and trunk. Educational objective: Vitiligo is caused by regional destruction of melanocytes, most likely due to an autoimmune etiology. It is often associated with other autoimmune conditions and is usually slowly progressive. The diagnosis is made on clinical grounds, and topical or systemic corticosteroids are the most common first-line intervention. References: Vitiligo: pathogenesis, clinical variants and treatment approaches. (http://www.ncbi.nlm.nih.gov/pubmed/26724277)

A 65-Year-Old Man Comes to the Office Due to a Skin