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5 Posts

mitty
Forum Guru

Topics: 52
Posts: 376

08/11/06 - 10:50 AM

A 23-year-old woman has hypocalcemia and hyperphosphatemia. She is short with a round face and has two short metacarpals in each hand. A sister has similar findings. Which laboratory values would be expected in this patient?

A. Decreased parathyroid hormone (PTH) and guanine nucleotide binding protein
B. Decreased PTH and increased guanine nucleotide binding protein
C. Increased PTH and decreased guanine nucleotide binding protein
D. Increased PTH and increased guanine nucleotide binding protein
E. Normal PTH and guanine nucleotide binding protein

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drpkaur
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Topics: 195
Posts: 808

08/11/06 - 11:27 AM

pseudohypoparathyroidism-due to deficiency of Gs proteins in kidney and bone.

C.....

vallia
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Topics: 98
Posts: 889

08/11/06 - 11:39 AM

it is not something related to Turner syndrome? please explain

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suv
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Topics: 43
Posts: 233

08/11/06 - 02:05 PM

the findings are consistent with pseudohypoparathyroidism
this is a autosomal recessive condition in which the kidneys are unresponsive to PTH due to decreased expression of Gs proteins.
Findings are hypocalcemia, increased PTH ,short stature and shortened 3rd 4th & 5th metacarpals.

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blueocean
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Topics: 15
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08/11/06 - 02:17 PM

Hypoparathyroidism=Albright hereditary osteodystrophy (AHO); the patients present with PTH-resistant hypocalcemia and hyperphosphatemia along with developmental and skeletal defects: short stature, rounded face, shortened fourth metacarpals and other bones of the hand and feet, obesity, dental hypoplasia, and soft tissue calcifications/ossifications. In addition, administration of PTH failed to produce the expected phosphaturia or to stimulate renal production of cyclic adenosine monophosphate (cAMP).
The molecular defects in the gene (GNAS1) encoding the alpha subunit of the stimulatory G protein (Gsa) ;GNAS1 gene is not sufficient in all tissues.

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