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113.A 46-year-old woman presents with pain in the left leg that worsens on
weight bearing. An x-ray shows demineralization, and a decalcified (EDTA-
treated) biopsy shows reduction in bone quantity. The patient had undergone
menopause at age 45 without estrogen replacement. She reports long-standing
diarrhea. In addition, laboratory tests show low levels of 1, 25-hydroxyvita-
min D, calcium, and phosphorus and elevated alkaline phosphatase. A second
bone biopsy, which was not decalcified, shows uncalcified osteoid on all the
bone surfaces. On the basis of these data, your diagnosis would be which of
the following?


a. Osteoporosis
b. Osteomalacia
c. Scurvy
d. Paget’s disease
e. Hypoparathyroidism


114.Patients with Cushing’s syndrome often show osteoporotic changes.
Which of the following is involved in the etiology of osteoporosis induced
by Cushing’s syndrome?


a. Decreased glucocorticoid levels that result in decreased quality of the bone
deposited
b. Excess deposition of osteoid
c. Stimulation of intestinal calcium absorption
d. Decreased PTH levels
e. Bone fragility resulting from excess bone resorption


115.A newborn girl is born with a small mouth, rather widely spaced eyes
and low-set ears. Genetic analysis shows a microdeletion on chromosome
22q11.2 leading to a diagnosis of an anomaly which results from failure of
the normal development of the third and fourth branchial pouches during
embryonic development. Which of the following would be expected to
occur in a child with this anomaly?


a. Absence of the parafollicular cells
b. Increased numbers of cells in the deep cortex of the lymph nodes
c. Tetany
d. Excess activity of osteoclasts
e. Increased Ca^2 +levels in the blood


200 Anatomy, Histology, and Cell Biology

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