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Embryology 5

A 21-year-old man presents to a dermatologist for a concern about loss of skin pigmentation in a patchy distribution over the past 6 months. He denies itching or scaling of the lesions. He has type 1 diabetes mellitus which is controlled with insulin therapy. Vital signs are within normal limits. Physical examination reveals well-defined, depigmented macules on the skin that are coalescing into larger patches of pigment loss that are surrounded by normal skin. Under a Wood’s lamp, the depigmented areas emit a bright blue-white fluorescence.

Which of the following structures has the same embryonic origin as the cells involved in this patient’s disease process?

  • A) Adrenal cortex
  • B) Parathyroid glands
  • C) Spleen
  • D) Sweat glands
  • E) Thyroid gland


Husban Hamil


Dr. Ted O'Connell