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| ==Pseudohypoparathyroidism==
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| __NOTOC__
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| ==Overview==
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| Pseudohypoparathyroidism (PHP) refers to a group of rare [[endocrine]] disorders characterized by end organ resistance to the action of [[parathyroid hormone]] (PTH), manifestations include [[hypocalcemia]], [[hyperphosphatemia]], and increased serum concentration of [[PTH]].
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| Development of pseudohypoparathyroidism is the result from multiple genetic mutations involving mainly the [[GNAS1|GNAS]] gene.
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|
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| ==Historical Perspective==
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| *In 1942, Fuller albright, an American endocrinologist, first discovered pseudohypoparathyroidim. Pseudohypoparathyoroidism is the first hormone resistance syndrome to be discovered.<ref>{{cite journal |vauthors=Albright F, Burnett CH, Smith PH, Parson |date=1942 |title=Pseudohypoparathyroidism- An example of ‘Seabright-Bantam syndrome’ |url= |journal= Endocrinology |volume=30 |issue= |pages=922–32 |doi= |access-date= }}</ref>
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| *In the same year, Albright hereditary osteodystrophy was clinically described together with pseudohypoparathyroidism. <ref name="pmid5002252">{{cite journal |vauthors=Eyre WG, Reed WB |title=Albright's hereditary osteodystrophy with cutaneous bone formation |journal=Arch Dermatol |volume=104 |issue=6 |pages=634–42 |year=1971 |pmid=5002252 |doi= |url=}}</ref>
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|
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| ==Classification==
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| *Pseudohypoparathyroidism is classified based on the measurement of serum and urinary [[cAMP]] and [[phosphate]] excretion levels after the injection of biologically active [[PTH|parathyroid hormone]] into following types:<ref name="pmid11117980">{{cite journal |vauthors=Marx SJ |title=Hyperparathyroid and hypoparathyroid disorders |journal=N. Engl. J. Med. |volume=343 |issue=25 |pages=1863–75 |year=2000 |pmid=11117980 |doi=10.1056/NEJM200012213432508 |url=}}</ref>
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| **Pseudohypoparathyroidism type I
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| **Pseudohypoparathyroidism type II
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|
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| *Pseudohypoparathyroidism type 1 is further classified into following subtype:<ref name="pmid11117980">{{cite journal |vauthors=Marx SJ |title=Hyperparathyroid and hypoparathyroid disorders |journal=N. Engl. J. Med. |volume=343 |issue=25 |pages=1863–75 |year=2000 |pmid=11117980 |doi=10.1056/NEJM200012213432508 |url=}}</ref>
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| **Pseudohypoparathyroidism type 1a
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| **Pseudohypoparathyroidism type 1b
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| **Pseudohypoparathyroidism type 1c.
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| **Pseudopseudohypoparathyroidism
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| *Other forms of [[PTH|parathyroid hormone]] resistance include :
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| **Blomstrand Syndrome
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| **Acrodysostosis type 1
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| **Acrodysostosis type 2
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|
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| ==Pathophysiology==
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| *Pseudohypoparathyroidism is characterized by end organ resistance to [[parathyroid hormone]].
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| *[[Parathyroid hormone]] effect is mediated by the [[parathyroid hormone receptor type 1]], which acts on a stimulatory [[guanine-nucleotide–binding (Gs) protein]], which is composed of three subunits (α, β, and γ). The [[GNAS1]] gene encodes Gsα subunit that mediates [[cyclic AMP]] stimulation by [[parathyroid hormone]] and by several other peptide hormones, including [[thyrotropin]].<ref name="pmid17986833">{{cite journal |vauthors=Spiegel AM |title=Inherited endocrine diseases involving G proteins and G protein-coupled receptors |journal=Endocr Dev |volume=11 |issue= |pages=133–44 |year=2007 |pmid=17986833 |doi=10.1159/0000111069 |url=}}</ref>
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| *Gene mutation results in failure of signal transduction through Gsα inability to activate [[Adenylate cyclase|adenyl cyclase]] that results in resistance of target tissues to [[parathyroid hormone]] evidenced by [[hypocalcemia]] and [[hyperphosphatemia]], in the presence of high plasma [[Parathyroid hormone|PTH]] level.<ref name="pmid4309802">{{cite journal |vauthors=Chase LR, Melson GL, Aurbach GD |title=Pseudohypoparathyroidism: defective excretion of 3',5'-AMP in response to parathyroid hormone |journal=J. Clin. Invest. |volume=48 |issue=10 |pages=1832–44 |year=1969 |pmid=4309802 |pmc=322419 |doi=10.1172/JCI106149 |url=}}</ref>
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| *Blomstrand's Chondrodystrophy is lethal prenatally characterized by abnormal [[Endochondral ossification|endochondral]] bone formation with prematurely occurring [[mineralization]] of the [[cartilaginous]] bone templates.
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| *Acrodysostosis patients have resistance to [[parathormone]] with normal [[calcium]] and [[phosphorus]], in addition to resistance [[thyroid-stimulating hormone]] and [[growth hormone releasing hormone]].
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|
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| Genetic mutations associated with parathyroid hormone resistance are discussed below <ref name="pmid23076042">{{cite journal |vauthors=Levine MA |title=An update on the clinical and molecular characteristics of pseudohypoparathyroidism |journal=Curr Opin Endocrinol Diabetes Obes |volume=19 |issue=6 |pages=443–51 |year=2012 |pmid=23076042 |pmc=3679535 |doi=10.1097/MED.0b013e32835a255c |url=}}</ref><ref name="pmid21816789">{{cite journal |vauthors=Mantovani G |title=Clinical review: Pseudohypoparathyroidism: diagnosis and treatment |journal=J. Clin. Endocrinol. Metab. |volume=96 |issue=10 |pages=3020–30 |year=2011 |pmid=21816789 |doi=10.1210/jc.2011-1048 |url=}}</ref><ref name="pmid25891861">{{cite journal |vauthors=Lee S, Mannstadt M, Guo J, Kim SM, Yi HS, Khatri A, Dean T, Okazaki M, Gardella TJ, Jüppner H |title=A Homozygous [Cys25]PTH(1-84) Mutation That Impairs PTH/PTHrP Receptor Activation Defines a Novel Form of Hypoparathyroidism |journal=J. Bone Miner. Res. |volume=30 |issue=10 |pages=1803–13 |year=2015 |pmid=25891861 |pmc=4580526 |doi=10.1002/jbmr.2532 |url=}}</ref><ref name="pmid9649554">{{cite journal |vauthors=Jobert AS, Zhang P, Couvineau A, Bonaventure J, Roume J, Le Merrer M, Silve C |title=Absence of functional receptors for parathyroid hormone and parathyroid hormone-related peptide in Blomstrand chondrodysplasia |journal=J. Clin. Invest. |volume=102 |issue=1 |pages=34–40 |year=1998 |pmid=9649554 |pmc=509062 |doi=10.1172/JCI2918 |url=}}</ref><ref name="pmid22464250">{{cite journal |vauthors=Michot C, Le Goff C, Goldenberg A, Abhyankar A, Klein C, Kinning E, Guerrot AM, Flahaut P, Duncombe A, Baujat G, Lyonnet S, Thalassinos C, Nitschke P, Casanova JL, Le Merrer M, Munnich A, Cormier-Daire V |title=Exome sequencing identifies PDE4D mutations as another cause of acrodysostosis |journal=Am. J. Hum. Genet. |volume=90 |issue=4 |pages=740–5 |year=2012 |pmid=22464250 |pmc=3322219 |doi=10.1016/j.ajhg.2012.03.003 |url=}}</ref><ref name="pmid21651393">{{cite journal |vauthors=Linglart A, Menguy C, Couvineau A, Auzan C, Gunes Y, Cancel M, Motte E, Pinto G, Chanson P, Bougnères P, Clauser E, Silve C |title=Recurrent PRKAR1A mutation in acrodysostosis with hormone resistance |journal=N. Engl. J. Med. |volume=364 |issue=23 |pages=2218–26 |year=2011 |pmid=21651393 |doi=10.1056/NEJMoa1012717 |url=}}</ref>
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| {| class="wikitable"
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| ! colspan="2" |Type of pseudohyoparathyroidism
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| !Molecular Defect
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| !Origin Of Mutation
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| !Inheritence
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| |-
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| | rowspan="5" |Pseudohypoparathyroidism type I
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| |Pseudohypoparathyroidism type 1a
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| |[[Heterozygous]] ''[[GNAS1|GNAS]]'' inactivating mutations that reduce expression or function of Gα<sub>s</sub>
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| |Maternal
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| |[[Autosomal dominant]]
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| |-
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| | rowspan="2" |Pseudohypoparathyroidism type 1b
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| |[[Familial]]- [[heterozygous]] deletions in ''[[STX16|STX]]16'', NESP55, and/or AS exons or loss of [[methylation]] at ''[[GNAS1|GNAS]]''
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| |Maternal
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| |[[Autosomal dominant]]
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| |-
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| |Sporadic- paternal [[Uniparental disomy]] of chromosome 20q in some or [[methylation]] defect affecting all four ''[[GNAS1|GNAS]]'' DMRs
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| |Maternal
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| |[[Genomic imprinting]]
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| |-
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| |Pseudohypoparathyroidism type 1c
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| |[[Heterozygous]] ''[[GNAS1|GNAS]]'' inactivating mutations that reduce expression or function of Gα<sub>s</sub>
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| |Maternal
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| |[[Autosomal dominant]]
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| |-
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| |Pseudopseudohypoparathyroidism
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| |Combination of inactivating mutations of ''[[GNAS1]]'' and [[Albright's hereditary osteodystrophy|Albright's osteodystrophy]]
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| |Paternal
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| |[[Genomic imprinting]]
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| |-
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| | colspan="2" |Pseudohypoparathyroidism type II
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| |Insufficient data to suggest genetic or familial source
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| |N/A
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| |N/A
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| |-
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| | colspan="2" |Blomstrand chondrodysplasia
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| |Homozygous or heterozygous mutations in both alleles encoding the type 1 parathyroid hormone receptor
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| |N/A
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| |[[Autosomal recessive]]
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| |-
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| | colspan="2" |Acrodysostosis type 1
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| |''PRKAR1A'' germ-line mutation in the encoding gene
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| |N/A
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| |[[Autosomal dominant]]
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| |-
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| | colspan="2" |Acrodysostosis type 2
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| |''Phosphodiesterase 4D (PDE4D) gene''
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| |N/A
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| |[[Autosomal dominant]]
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| |}
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|
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| ==Causes==
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| Pseudohypoparathyroidism is caused by mutations involving primarily the [[GNAS1|GNAS]] gene that results in end organ resistance to [[parathyroid hormone]]. For a complete review of genes involved in pseudohypoparathyroidism and associated parathyroid hormone resistance click here.
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|
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| ==Differentiating ((Page name)) from Other Diseases==
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| [Disease name] must be differentiated from other diseases that cause [clinical feature 1], [clinical feature 2], and [clinical feature 3], such as [differential dx1], [differential dx2], and [differential dx3].
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|
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| OR
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| [Disease name] must be differentiated from [[differential dx1], [differential dx2], and [differential dx3].
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|
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| ==Epidemiology and Demographics==
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|
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| ===Prevalence===
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| *In Japan, the [[prevalence]] of pseudohypoparathyroidism ranges from a low of 0.26 per 100,000 persons to a high of 0.42 per 100,000 persons with an average [[prevalence]] of 0.34 per 100,000 persons.<ref name="pmid10695258">{{cite journal |vauthors=Nakamura Y, Matsumoto T, Tamakoshi A, Kawamura T, Seino Y, Kasuga M, Yanagawa H, Ohno Y |title=Prevalence of idiopathic hypoparathyroidism and pseudohypoparathyroidism in Japan |journal=J Epidemiol |volume=10 |issue=1 |pages=29–33 |year=2000 |pmid=10695258 |doi= |url=https://www.jstage.jst.go.jp/article/jea1991/10/1/10_1_29/_pdf}}</ref>
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| *In Italy, the estimated [[prevalence]] of PHP type 1a, type1b, and PPHP is 1 per 150,000.<ref name="urlOrphanet: Pseudohypoparat">{{cite web |url=http://www.orpha.net/consor/cgi-bin/Disease_Search.php?lng=EN&data_id=12935&Disease_Disease_Search_diseaseGroup=Pseudohypoparathyroidism&Disease_Disease_Search_diseaseType=Pat&Disease(s)/group%20of%20diseases=Pseudohypoparathyroidism&title=Pseudohypoparat |title=Orphanet: Pseudohypoparat |format= |work= |accessdate=}}</ref>
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|
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| ==Risk Factors==
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| The most potent risk factor in the development of pseudohypoparathyroidism is a positive family history for [[GNAS1|GNAS]] mutation.
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|
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| ==Screening==
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| There is insufficient evidence to recommend routine screening for pseudohypoparathyroidism.
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|
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| ==Complications==
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| Complications that can develop as a result of pseudohypoparathyroidism are
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| *[[Seizures]] (children).
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| *[[Hypothyroidism]] due to associated resistance to [[thyrotropin]].
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| *[[Gonadotropin]] or [[GHRH]] resistance.
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| *Patients may develop [[hypocalcemia]] resulting in<ref name="pmid18663313">{{cite journal |vauthors=Shalitin S, Davidovits M, Lazar L, Weintrob N |title=Clinical heterogeneity of pseudohypoparathyroidism: from hyper- to hypocalcemia |journal=Horm. Res. |volume=70 |issue=3 |pages=137–44 |year=2008 |pmid=18663313 |doi=10.1159/000137658 |url=}}</ref>
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| **[[Paresthesias]]
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| ** Muscular cramping
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| **[[Tetany]]
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| **[[Carpopedal spasm]]
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|
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| *Subcutaneous [[calcification]] in [[neonatal]] period.<ref name="pmid20011056">{{cite journal |vauthors=Adachi M, Muroya K, Asakura Y, Kondoh Y, Ishihara J, Hasegawa T |title=Ectopic calcification as discernible manifestation in neonates with pseudohypoparathyroidism type 1a |journal=Int J Endocrinol |volume=2009 |issue= |pages=931057 |year=2009 |pmid=20011056 |pmc=2778176 |doi=10.1155/2009/931057 |url=}}</ref>
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|
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| *Reproductive dysfunction is seen in patients with pseudohypoparathyroidism 1a. Women may experience delayed [[puberty]], [[oligomenorrhea]], and [[infertility]].In men decreased [[Fertility]] may present with maturation arrest of [[Testes]] and [[cryptorchidism]].
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| *Pseudohypoparathyroidism type 1b patients are at risk of developing tertiary [[hyperparathyroidism]] and [[hyperparathyroid]] bone disease. <ref name="pmid22736772">{{cite journal |vauthors=Neary NM, El-Maouche D, Hopkins R, Libutti SK, Moses AM, Weinstein LS |title=Development and treatment of tertiary hyperparathyroidism in patients with pseudohypoparathyroidism type 1B |journal=J. Clin. Endocrinol. Metab. |volume=97 |issue=9 |pages=3025–30 |year=2012 |pmid=22736772 |pmc=3431579 |doi=10.1210/jc.2012-1655 |url=}}</ref>
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| *[[Osteopenia]] and [[rickets]] in peudohypoparathyroidism-1a is associated with variable [[osteoclast]] responsiveness to [[parathyroid]] hormone.<ref name="pmid18805917">{{cite journal |vauthors=Balavoine AS, Ladsous M, Velayoudom FL, Vlaeminck V, Cardot-Bauters C, d'Herbomez M, Wemeau JL |title=Hypothyroidism in patients with pseudohypoparathyroidism type Ia: clinical evidence of resistance to TSH and TRH |journal=Eur. J. Endocrinol. |volume=159 |issue=4 |pages=431–7 |year=2008 |pmid=18805917 |doi=10.1530/EJE-08-0111 |url=}}</ref>
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| ==Prognosis==
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| Insufficient data is available to determine the long term outcomes of pseudohypoparathyroidism. In some patients [[calcium]] [[homeostasis]] adapts to [[parathyroid]] hormone resistance resulting in resolution of [[hypocalcemia]] while others who do not adapt to [[parathyroid hormone]] resistance are managed with lifelong [[calcium]] supplementation. Long term [[levothyroxine]] is used in patients with associated [[Hypothyroidism|hypothyroidism.]]
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| ==Diagnosis==
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|
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| ===Diagnostic Criteria===
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| The diagnosis of pseudohypoparathyroidism Type 1a patients includes:
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| *Clinical features of [[Albright's hereditary osteodystrophy]]
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| *[[Parathyroid]] hormone resistance evidenced by
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| **[[Hypocalcemia]]
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| **[[Hyperphosphatemia]]
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| **Elevated serum concentration of [[parathyroid]] hormone
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| **Diminished urinary [[cAMP]] response after administration of the biosynthetic N-terminal fragment of [[parathyroid]] hormone.
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|
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| ===History and Symptoms===
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| *A positive family history of pseudohypoparathyroidism is suggestive of the [[autosomal dominant]] inheritance.
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|
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| *The most common symptoms of pseudohypoparathyroidism type 1a include [[short stature]],[[mental retardation]] associated with [[Albright's hereditary osteodystrophy|Albright hereditary Osteodystrophy]] [[phenotype]].
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|
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| *Common symptoms due to associated [[hypocalcemia]] include
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| **[[Paresthesia|Paresthesias]] (peri-oral, extremities)
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| **[[Muscle twitching]]
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| **[[Carpopedal spasm]]
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| **[[Seizures]]
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| **[[Prolonged QT interval]]
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| **[[Hypotension]]
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| **[[Arrhythmia]].
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| ===Physical Examination===
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| *Patients with pseudohypoparathyroidism type1A , type 1c and pseudopseudohypoparathyroidism presents by the second decade of life with characteristic physical features of [[Albright's hereditary osteodystrophy]] like:
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| **Subcutaneous ossifications
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| **Shortening of third, fourth, and fifth [[metacarpals]] and [[metatarsals]]
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| **Round face
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| **Obesity
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| **Frontal bossing
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| **Dental [[hypoplasia]]
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|
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| *Pseudohypoparathyroidism Type 1B isolated resistance to [[parathyroid hormone]] without the associated clinical features of [[Albright's hereditary osteodystrophy|Albright's osteodystrophy]]. Mild [[brachydactyly]] is seen in some cases.
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|
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| *Blomstrand's chondrodystrophy presents with short limbs due to characteristic growth impairment.Secondary [[hyperplasia]] of the [[parathyroid glands]] occurs as a result of associated [[hypocalcemia]].
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|
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| *Acrodysostosis characteristic physical findings include<ref name="pmid5551869">{{cite journal |vauthors=Robinow M, Pfeiffer RA, Gorlin RJ, McKusick VA, Renuart AW, Johnson GF, Summitt RL |title=Acrodysostosis. A syndrome of peripheral dysostosis, nasal hypoplasia, and mental retardation |journal=Am. J. Dis. Child. |volume=121 |issue=3 |pages=195–203 |year=1971 |pmid=5551869 |doi= |url=}}</ref>
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| **Short hands;
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| **Small, flat, upturned nose;
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| **Mild to moderate intellectual disability.
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| **Hypoplastic genitalia
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| **[[Cryptorchidism]]
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|
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| ===Laboratory Findings===
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| *The diagnosis of pseudohypoparathyroidism is made by measurement of variations in serum [[calcium]], [[phosphorus]], [[cAMP]] and [[calcitriol]] and in urinary [[Cyclic adenosine monophosphate|cAMP]] and [[phosphorus]] excretion helps in assessment of skeletal and renal responsiveness to [[parathyroid]] hormone.
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| *Laboratory findings consistent with the diagnosis of pseudohypoparathyroidism include
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| **[[Hypocalcemia]]
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| **[[Hyperphosphatemia]]
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| **Elevated serum concentration of [[parathyroid hormone]]
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| **Diminished urinary [[cAMP]] response after administration of the biosynthetic N-terminal fragment of [[parathyroid]] hormone
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| **[[Secondary hyperparathyroidism]] and [[hyperparathyroid]] bone disease due to the [[parathyroid]] hormone resistance .
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|
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| *Immunoradiometric assay (IRMA) can be used to measure serum [[parathyroid]] hormone concentration.<ref name="pmid18663313">{{cite journal |vauthors=Shalitin S, Davidovits M, Lazar L, Weintrob N |title=Clinical heterogeneity of pseudohypoparathyroidism: from hyper- to hypocalcemia |journal=Horm. Res. |volume=70 |issue=3 |pages=137–44 |year=2008 |pmid=18663313 |doi=10.1159/000137658 |url=}}</ref>
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|
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| *Assessment of [[thyroid function tests]], [[gonadotropin]], [[testosterone]], [[estrogen]] and insulin like growth factor will help in identification of any associated underlying hormonal dysfunction
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|
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| ===Electrocardiogram===
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| An [[ECG]] may be helpful in the diagnosis of cardiac dysfunction associated with the pseudohypoparathyroidism. Findings on an ECG suggestive of cardiac dysfunction due to [[hypocalcemia]] associated with pseudohypoparathyroidism include [[prolonged QT]] interval.
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|
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| ===X-ray===
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| An [[x-ray]] of the hand may be helpful in the diagnosis of [[pseudohypoparathyroidism]]. Findings on an x-ray include short distal phalanx of thumb and short third to fifth metacarpals associated with features of [[Albright's hereditary osteodystrophy|albright hereditary osteodystrophy.]]
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|
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| An [[x-ray]] of the hand may be helpful in the diagnosis of acrodysostosis. Findings on an x-ray of hand include shortened [[metacarpals]] with cone [[epiphyses]]. The spine may also be affected with loss of [[caudal]] widening of interpedicular distance, which may correlate with stenosis of the spinal canal<ref name="pmid5551869">{{cite journal |vauthors=Robinow M, Pfeiffer RA, Gorlin RJ, McKusick VA, Renuart AW, Johnson GF, Summitt RL |title=Acrodysostosis. A syndrome of peripheral dysostosis, nasal hypoplasia, and mental retardation |journal=Am. J. Dis. Child. |volume=121 |issue=3 |pages=195–203 |year=1971 |pmid=5551869 |doi= |url=}}</ref>
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|
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| ===Echocardiography or Ultrasound===
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| There are no [[echocardiography]]/[[ultrasound]] findings associated with pseudohypoparathyroidism.
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|
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| ===CT scan===
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| Findings on [[CT scan]] suggestive of pseudohypoparathyroidism in some patients includes include symmetric calcifications in [[basal ganglia]], perivascular calcifications in soft tissues. <ref name="pmid1638002">{{cite journal |vauthors=Nekula J, Urbanek K, Buresova J |title=[Radiological findings in pseudohypoparathyroidism] |language=German |journal=Rofo |volume=157 |issue=1 |pages=34–6 |year=1992 |pmid=1638002 |doi=10.1055/s-2008-1032961 |url=}}</ref>
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|
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| ===MRI===
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| Findings on brain [[MRI]] in pseudohypoparathyroidism Ia patients, particularly those with abnormal [[neurological examination]] or [[developmental delay]] include [[Arnold-Chiari malformation|Chiari Malformation-Type I]] .
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|
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| ===Other Imaging Findings===
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| There are no other imaging findings associated with psuedohypoparathyroidism.
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|
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| ===Other Diagnostic Studies===
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| *Genetic testing may be helpful in the diagnosis of pseudohypoparathyroidism. Analysis of the [[GNAS1|''GNAS1'' gene]] can confirm diagnosis and identify the different variants of PHP. Testing for paternal uniparental isodisomy of chromosome 20q or deletions in [[STX16|STX]]16 can also help in diagnosis of pseudohypoparathyroidism 1b. <ref name="pmid26943720">{{cite journal |vauthors=Clarke BL, Brown EM, Collins MT, Jüppner H, Lakatos P, Levine MA, Mannstadt MM, Bilezikian JP, Romanischen AF, Thakker RV |title=Epidemiology and Diagnosis of Hypoparathyroidism |journal=J. Clin. Endocrinol. Metab. |volume=101 |issue=6 |pages=2284–99 |year=2016 |pmid=26943720 |pmc=5393595 |doi=10.1210/jc.2015-3908 |url=}}</ref>
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|
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| *Gsα defects can be diagnosed by assessment of variations in [[platelet aggregation]] responses reflecting a patient's [[genotype]].<ref name="pmid18812479">{{cite journal |vauthors=Freson K, Izzi B, Labarque V, Van Helvoirt M, Thys C, Wittevrongel C, Bex M, Bouillon R, Godefroid N, Proesmans W, de Zegher F, Jaeken J, Van Geet C |title=GNAS defects identified by stimulatory G protein alpha-subunit signalling studies in platelets |journal=J. Clin. Endocrinol. Metab. |volume=93 |issue=12 |pages=4851–9 |year=2008 |pmid=18812479 |doi=10.1210/jc.2008-0883 |url=}}</ref>
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|
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| *Psuedohypoparathyroidism type 1b associated bone disease can be evaluated with [[bone mineral density]] (BMD) testing.
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|
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| ==Treatment==
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| ===Medical Therapy===
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| *The mainstay of treatment for pseudohypoparathyroidism is oral [[calcium]] and 1alpha-hydroxylated vitamin D metabolites, such as [[calcitriol]]. Other forms of Vitamin D cannot be used as [[parathyroid]] hormone resistance in the [[proximal tubule]] decreases the efficiency of production of 1,25(OH)2 vitamin D from 25-hydroxyvitamin D.
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| *The majority of cases of pseudohypoparathyroidism are self-limited and require only supportive care.
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| * The goal is to maintain serum [[calcium]] within the normal range to prevent [[hypercalciuria]] and to maintain [[parathyroid]] hormone levels within reference range which helps prevent bone remodeling and [[hyperparathyroid]] bone disease that can result from elevated [[parathyroid hormone]] level.
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| *Intravenous calcium is recommended for all patients who develop severe symptomatic [[hypocalcemia]]. Adult dosage is started 100 mg of elemental [[calcium]] (either [[calcium chloride]] or [[calcium gluconate]]) over 10 to 20 minutes. An additional dose of 100 mg/hr of [[elemental calcium]] can be infused if symptoms do not resolve, with close monitoring of [[calcium]] levels.Cardiac monitoring may help to guide therapy as rapid infusion of [[calcium]] can cause cardiac conduction defects;
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| * [[Parenteral|Parentera]]<nowiki/>l formulations available are [[calcium chloride]] and [[calcium gluconate]]; a 10-mL ampule of 10% [[calcium chloride]] contains 360 mg of [[elemental calcium]], and a 10-mL ampule of 10% [[calcium gluconate]] contains 93 mg of elemental [[calcium]].
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|
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| *For [[neonates]], [[infants]], and [[children]], the recommended initial dose is 0.5-1 mL/kg of 10% [[calcium gluconate]] administered over 5 minutes.
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|
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| ===Surgery===
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| *Surgery is not the first-line treatment option for patients with psuedohypoparathyroidism.
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| *Surgical resection of enlarged [[parathyroid glands]] is usually reserved for patients that develop [[tertiary hyperparathyroidism]] in pseudohypoparathyroidism 1b. Rarely, excision of extraskeletal [[osteomas]] is done to relieve associated pressure symptoms in patients. <ref name="pmid22736772" />
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| ===Primary Prevention===
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| Effective measures for the primary prevention of pseudohypoparathyroidism include [[genetic counseling]] in inherited cases.
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| ===Secondary Prevention===
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| Monitor therapy with regular serum and urinary [[calcium]] measurements.Pseudohypoparathyroidism type 1b patients at an increased risk of developing [[hyperparathyroidism]] and [[hyperparathyroid]] bone disease should be maintained at sufficient doses of [[calcium]] and [[vitamin D]] to maintain serum [[calcium]] and [[PTH]] levels within the normal range. Monitor therapy with regular serum and urinary [[calcium]] measurements.
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| ==References==
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| {{reflist|2}}
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