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__NOTOC__
'''For patient information click [[{{PAGENAME}} (patient information)|here]]'''
{{Infobox_Disease
{{Infobox_Disease
| Name          = Marfan syndrome
| Name          = Marfan syndrome
| Image          = Marfansyndrome.jpg
| Image          = Marfansyndrome2.jpg
| Caption        =  
| Caption        =
| DiseasesDB    = 7845
| DiseasesDB    = 7845
| ICD10          = {{ICD10|Q|87|4|q|80}}
| ICD10          = {{ICD10|Q|87|4|q|80}}
| ICD9          = {{ICD9|759.82}}
| ICD9          = {{ICD9|759.82}}
| ICDO          =  
| ICDO          =
| OMIM          = 154700
| OMIM          = 154700
| MedlinePlus    = 000418
| MedlinePlus    = 000418
| eMedicineSubj  = ped
| eMedicineTopic = 1372
| eMedicine_mult = {{eMedicine2|orthoped|414}}
| MeshID        = C17.300.500
| MeshID        = C17.300.500
}}
}}
{{SI}}
{{Marfan's syndrome}}
 
'''Editors-In-Chief:''' [[William James Gibson]], [[C. Michael Gibson, M.S., M.D.]]
 
'''Associate Editor-In-Chief:''' {{CZ}}
 
{{Editor Help}}
 
==Overview==
 
'''Marfan syndrome''' (or Marfan's syndrome) is a connective tissue disorder most often caused by defects in the [[Fibrillin-1 gene]] ([[FBN1]]). Patients with Marfan's syndrome are at significant risk of skeletal, cardiovascular and ocular complications.  People with Marfan's are typically tall, with long [[Limb (anatomy)|limb]]s and long thin fingers.
 
==Background==
In 1896, French pediatrician Antoine-Bernard Jean Marfan described a five year old girl, Gabrielle P, with skeletal features characteristic of Marfan Syndrome, pieds d’aragne (French, spider feet) and dolichostenomalie (French, longheadedness meaning long limbs). In 1902, Emile Charles Achard described a similar syndrome, reporting scoliosis and arachnodactyly (abnormally long and slender fingers) as essential features <ref name="pmid13590978">{{cite journal |author=BOYER BE, MARTIN MM |title=Marfan's syndrome; report of a case manifesting a giant bone cyst of the mandible and multiple (110) basal cell carcinomata |journal=[[Plastic and Reconstructive Surgery and the Transplantation Bulletin]] |volume=22 |issue=3 |pages=257–63 |year=1958 |month=September |pmid=13590978 |doi= |url= |issn= |accessdate=2010-12-22}}</ref>.  Salle contributed the observation in 1912 that patients with arachnodactyly had thickened mitral leaflets, ocular abnormalities and increase in eosinophilic cells in the pituitary <ref name="pmid14360720">{{cite journal |author=BLACK HH, LANDAY LH |title=Marfan's syndrome; report on five cases in one family |journal=[[A.M.A. American Journal of Diseases of Children]] |volume=89 |issue=4 |pages=414–20 |year=1955 |month=April |pmid=14360720 |doi= |url= |issn= |accessdate=2010-12-22}}</ref>.  The observation that ectopic lens was associated with other symptoms was first made by Boerger in 1914 .  Weve established the autosomal dominant inheritance of the disease, still known as arachnodactyly, in 1931. Weve postulated that the syndrome arose from a defect in mesenchymal tissue and thus designated the syndrome dystrophia mesodermalis congenita typus Marfanis.  Association of the syndrome with aortic dilation and dissection, the major causes of mortality in individuals with Marfan Syndrome were identified in 1943 by RW Baer et al. as well as Etter and Glover.  Harry C Deitz finally established the molecular basis of Marfan Syndrome in his landmark 1991 Nature paper, showing that mutations in the FBN1 gene are responsible for the disease <ref name="pmid1852208">{{cite journal |author=Dietz HC, Cutting GR, Pyeritz RE, Maslen CL, Sakai LY, Corson GM, Puffenberger EG, Hamosh A, Nanthakumar EJ, Curristin SM |title=Marfan syndrome caused by a recurrent de novo missense mutation in the fibrillin gene |journal=[[Nature]] |volume=352 |issue=6333 |pages=337–9 |year=1991 |month=July |pmid=1852208 |doi=10.1038/352337a0 |url=http://dx.doi.org/10.1038/352337a0 |issn= |accessdate=2010-12-22}}</ref>.
 
==Pathophysiology==
Marfan syndrome has been linked to a defect in the ''FBN1'' [[gene]] on [[chromosome]] 15,<ref>{{cite journal | author = McKusick V | title = The defect in Marfan syndrome. | journal = Nature | volume = 352 | issue = 6333 | pages = 279-81 | year = 1991 | id = PMID 1852198}}</ref> which [[Genetics|encodes]] a [[glycoprotein]] called [[fibrillin]]-1. Fibrillin is essential for the formation of the [[elastic fiber]]s found in connective tissue, as it provides the scaffolding for [[tropoelastin]].<ref name="robspath">{{cite book | title=Robbins Pathologic Basis of Disease| last=Cotran| coauthors=Kumar, Collins| publisher=W.B Saunders Company| location=Philadelphia| id=0-7216-7335-X}}</ref> Elastic fibers are found throughout the body but are particularly abundant in the [[aorta]], [[ligament]]s and the [[Zonule of Zinn|ciliary zonule]]s  of the eye, consequently these areas are among the worst affected.  Without the structural support provided by fibrillin many connective  tissues are weakened, which can have severe consequences for support  and  stability.
 
Marfan syndrome is inherited as a [[Autosomal dominant|dominant]] trait.  In so far as the pattern of inheritance is [[Dominance (genetics)|dominant]],  people who have inherit just one affected FBN1 gene from either parent  will develop Marfan syndrome. This expression of the syndrome can range  from mild to severe.
 
A related disease has been found in mice, and the  study of mouse  fibrillin synthesis and secretion, and connective tissue  formation, has  begun to further our understanding of Marfan syndrome in  humans. It  has been found that simply reducing the level of normal  fibrillin-1  causes a Marfan-related disease in mice.<ref name="micefib">{{cite journal | author=Lygia Pereira, ''et al.''|  title=Pathogenetic sequence for aneurysm revealed in mice  underexpressing fibrillin-1| journal=Proceedings of the National  Academy  of Sciences| year=1999| volume=96| issue=7| page=3819-3823|  url=http://www.pnas.org/cgi/content/full/96/7/3819}}</ref>
 
High levels of [[Transforming growth factor]] beta (TGFβ) are associated with inflammation and also play an important role in Marfan syndrome. Ordinarily, Fibrillin-1  binds TGFβ and inactivates it. In Marfan  syndrome, reduced levels of  fibrillin-1 allow activated TGFβ to damage  the lungs and heart. Researchers now believe that the inflammatory effects of TGF-β, on the lungs, heart valves, and aorta weaken the connective tissues and cause the features of Marfan syndrome. In so far as [[angiotensin II receptor blocker]]s ([[Angiotensin II receptor antagonists|ARBs]]) reduce TGF-β, these agents  have been administered  to young Marfan syndrome patients, and the expansion of the aorta was indeed reduced.<ref>{{cite journal |author=Pyeritz RE |title=A small molecule for a large disease |journal=N. Engl. J. Med. |volume=358 |issue=26 |pages=2829–31 |year=2008 |month=June |pmid=18579819 |doi=10.1056/NEJMe0804008}}</ref>
 
A defect  in the gene ''TGFβR2'' on [[chromosome]] 3, a [[receptor protein]] of TGFβ, has also been related to Marfan syndrome.<ref name="tgf2beta">{{Cite web|url=http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=gene&dopt=full_report&list_uids=7048|title=TGFBR2  transforming growth factor, beta receptor  II|publisher=NCBI|year=2007|author=Entrez Gene|format=Entrez gene entry}}</ref> Marfan syndrome can often be confused with [[Loeys-Dietz syndrome]], a similar connective tissue disorder resulting from mutations in the TGFβ receptor genes ''TGFβR1'' and ''TGFβR2''.<ref name="loeysdietz">{{Cite web|url=http://www.marfan.org/nmf/GetContentRequestHandler.do?menu_item_id=84|title=Related Disorders: Loeys-Dietz|publisher=National Marfan Foundation}}</ref>
 
==Differential Diagnosis==
 
The following disorders have similar signs and symptoms of Marfan syndrome:
 
* [[Arachnodactyly|Congenital Contractural Arachnodactyly (CCA) or Beals Syndrome]]
* [[Ehlers-Danlos syndrome]]
* [[Homocystinuria]]
* [[Loeys-Dietz syndrome]]
* [[MASS phenotype]]
* [[Stickler syndrome]]
 
==Etymology==
 
In 1896, French pediatrician Antoine-Bernard Jean Marfan described a five year old girl, Gabrielle P, with skeletal features characteristic of Marfan Syndrome1, pieds d’aragne (French, spider feet) and dolichostenomalie (French, longheadedness meaning long limbs). In 1902, Emile Charles Achard described a similar syndrome, reporting scoliosis and arachnodactyly (abnormally long and slender fingers) as essential features2.  Salle contributed the observation in 1912 that patients with arachnodactyly had thickened mitral leaflets, ocular abnormalities and increase in eosinophilic cells in the pituitary3,4.  The observation that ectopic lens was associated with other symptoms was first made by Boerger in 19145 .  Weve established the autosomal dominant inheritance of the disease, still known as arachnodactyly, in 19316. Weve postulated that the syndrome arose from a defect in mesenchymal tissue and thus designated the syndrome dystrophia mesodermalis congenita typus Marfanis.  Association of the syndrome with aortic dilation and dissection, the major causes of mortality in individuals with Marfan Syndrome were identified in 1943 by RW Baer et al. as well as Etter and Glover7,8.  Harry C Deitz finally established the molecular basis of Marfan Syndrome in his landmark 1991 Nature paper, showing that dysregulation of TGF-beta signaling is responsible for the observed manifestations9.
 
==Epidemiology==
 
Marfan syndrome affects males and females equally,<ref name="marorg">{{Cite web|url=http://www.marfan.org/nmf/GetSubContentRequestHandler.do?sub_menu_item_content_id=6&menu_item_id=3|title=The role of heredity and family history|publisher=National Marfan Foundation|year=1999}}</ref> and the mutation shows no geographical bias. Estimates indicate that approximately 60 000 (1 in 5000, or 0.02% of the population)<ref name="marorg"/> to 200 000<ref name="mednet">{{Cite web|url=http://www.medicinenet.com/script/main/art.asp?articlekey=63689|title=New, Deadly Relative of Marfan's Syndrome Discovered|publisher=MedicineNet.com|year=2006}}</ref> Americans have Marfan syndrome. Each parent with the condition has a 50% chance of passing it on to a child due to its [[autosomal dominant]] nature.  Most individuals with Marfan syndrome have another affected family member, but approximately 15-30% of all cases are due to ''[[de novo mutation|de novo]]'' [[genetic mutation]]s<ref name="robspath">{{cite book | title=Robbins Pathologic Basis of Disease| last=Cotran| coauthors=Kumar, Collins| publisher=W.B Saunders Company| location=Philadelphia| id=0-7216-7335-X}}</ref> &mdash; such spontaneous mutations occur in about 1 in 20 000 births. Marfan syndrome is also an example of [[dominant negative mutation]] and [[haploinsufficiency]].<ref name="Judge_et_al_2004">{{cite journal | last = Judge | first = Daniel P. | coauthors = Nancy J. Biery, Douglas R. Keene, Jessica Geubtner, Loretha Myers, David L. Huso, Lynn Y. Sakai, Harry C. Dietz | title = Evidence for a critical contribution of haploinsufficiency in the complex pathogenesis of Marfan syndrome. | journal = The Journal of Clinical Investigation | volume = 114 | issue = 2 | pages = 172-181 | doi = 10.1172/JCI200420641 | id = PMID 15254584 | url = http://www.jci.org/cgi/content/full/114/2/172}}</ref><ref name="Judge_et_al_2005">{{cite journal | last = Judge | first = Daniel P. | coauthors = Harry C. Dietz | title = Marfan's syndrome. | journal = Lancet | volume = 366 | issue = 9501 | pages = 1965-76 | year = 2005 | doi = 10.1016/S0140-6736(05)67789-6. | id = PMID 16325700 | url = http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=16325700}}</ref> It is associated with variable expressivity. [[Incomplete penetrance]], has not been definitively documented.
 
The prevalence of Marfan syndrome is 1 case per 3000 to 5000 individuals or .033 % (upper estimate) <ref name="pmid16325700">{{cite journal |author=Judge DP, Dietz HC |title=Marfan's syndrome |journal=[[Lancet]] |volume=366 |issue=9501 |pages=1965–76 |year=2005 |month=December |pmid=16325700 |pmc=1513064 |doi=10.1016/S0140-6736(05)67789-6 |url=http://linkinghub.elsevier.com/retrieve/pii/S0140-6736(05)67789-6 |issn= |accessdate=2010-12-22}}</ref>.  Neither location nor ethnicity appear to impact this statistic.  Populations of certain athletes such as basketball and volleyball players have been shown to have an increased incidence of Marfan syndrome (~0.5%) <ref name="pmid10740158">{{cite journal |author=Kinoshita N, Mimura J, Obayashi C, Katsukawa F, Onishi S, Yamazaki H |title=Aortic root dilatation among young competitive athletes: echocardiographic screening of 1929 athletes between 15 and 34 years of age |journal=[[American Heart Journal]] |volume=139 |issue=4 |pages=723–8 |year=2000 |month=April |pmid=10740158 |doi= |url=http://linkinghub.elsevier.com/retrieve/pii/S0002-8703(00)90055-3 |issn= |accessdate=2010-12-22}}</ref>, perhaps due to skeletal abnormalities associated with the syndrome.  While patients now have nearly normal life expectancies, in previous decades, patients’ life expectancies were significantly shortened by the risks of aortic dissection, valvular failure and congestive heart failure.  Together, these cardiovascular complications accounted for 90% of the mortality associated with Marfan syndrome such that in the 1970s, an affected individual would be expected to live only two-thirds as long as his unaffected counterparts <ref name="pmid5011789">{{cite journal |author=Murdoch JL, Walker BA, Halpern BL, Kuzma JW, McKusick VA |title=Life expectancy and causes of death in the Marfan syndrome |journal=[[The New England Journal of Medicine]] |volume=286 |issue=15 |pages=804–8 |year=1972 |month=April |pmid=5011789 |doi=10.1056/NEJM197204132861502 |url=http://www.nejm.org/doi/abs/10.1056/NEJM197204132861502?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%3dpubmed |issn= |accessdate=2010-12-22}}</ref>.
 
==Related disorders==
 
The following conditions that can result from having Marfan's syndrome and may also occur in people without any known underlying disorder. what leads doctors to a diagnosis of marfan syndrome is family history and a combination of major and minor indicators of the disorder that occur in one individual which is a rare manifestation in general population. Example: four skeletal signs with one or more signs in another body system such as ocular and cardiovascular in one individual. 
 
*[[Aortic aneurysm|Aortic aneurysm or dilatation]]
*[[Arachnodactyly]]
*[[Bicuspid aortic valve]]
*[[Cysts]]
*[[Craniosynostosis]]
*[[Cystic medial necrosis]]
*[[Dural ectasia]]
*[[Ectopia lentis]]
*[[Flat feet]]
*[[Gigantism]]
*[[Glaucoma]]
*[[Hernias]]
*[[Hyperflex|Hypermobility of the joints]]
*[[Malocclusion]]
*[[Mitral valve prolapse]]
*[[Myopia]]
*[[COPD|Obstructive lung disease]]
*[[Osteoarthritis]]
*[[Pectus carinatum]] or [[pectus excavatum|excavatum]]
*[[Pneumothorax]]
*[[Retinal detachment]]
*[[Scoliosis]]
*[[Sleep apnea]]
*[[Stretch marks]]
 
==Symptoms==
 
There are no signs or symptoms that are unique to Marfan syndrome. It is usually a single apparent sign or symptom that leads doctors to look for others and eventually to diagnose the syndrome, which affects connective tissue in diverse organs and systems. Even affected individuals in the same family might exhibit various combinations and severities of symptoms.


===Skeletal system===
'''Editors-In-Chief:''' [[William James Gibson]], [[C. Michael Gibson, M.S., M.D.]]; {{AE}} {{CZ}}; {{CA}}


The most readily visible signs are associated with the skeletal system.  Many individuals with Marfan Syndrome grow to above average height. Some have long slender limbs with fingers and toes that are also abnormally long and slender ([[arachnodactyly]]). An individual's arms may be disproportionately long.  In addition to affecting height and limb proportions, Marfan syndrome can produce other skeletal signs. Abnormal curvature of the [[Vertebral column|spine]] ([[scoliosis]]) is common, as is abnormal indentation ([[pectus excavatum]]) or protrusion ([[pectus carinatum]]) of the [[sternum]]. Other signs include abnormal joint flexibility, a high [[palate]], [[malocclusions]], flat feet, stooped shoulders, and unexplained [[stretch marks]] on the skin. Some people with Marfans have [[speech disorder|speech disorders]] resulting from symptomatic high palates and small jaws.
== [[Marfan's syndrome overview|Overview]] ==


===Eyes===
== [[Marfan's syndrome historical perspective|Historical Perspective]] ==
[[Image:Lens marfan.gif|thumb|left|160px|Lens dislocation in Marfan's syndrome, the lens was kidney-shaped and was resting against the [[ciliary body]].]]
Marfan syndrome can also seriously affect the eyes and vision. [[myopia|Nearsightedness]] and [[astigmatism (eye)|astigmatism]] are common, but farsightedness can also result. <ref name="mayo-gen">{{Cite web|url=http://www.mayoclinic.com/health/marfan-syndrome/DS00540/DSECTION=2|title=Marfan Syndrome|accessdate=January 12 2007|dateformat=mdy|publisher=Mayo Clinic}}</ref>


[[Subluxation]] (dislocation) of the crystalline [[lens (anatomy)|lens]] in one or both eyes (''[[ectopia lentis]]'') (in 80% of patients) also occurs and may be detected by an [[ophthalmologist]] or [[optometrist]] using a [[Slit lamp|slit-lamp]] biomicroscope. <ref name="mayo-gen">{{Cite web|url=http://www.mayoclinic.com/health/marfan-syndrome/DS00540/DSECTION=2|title=Marfan Syndrome|accessdate=January 12 2007|dateformat=mdy|publisher=Mayo Clinic}}</ref>
== [[Marfan's syndrome pathophysiology|Pathophysiology]] ==


In Marfan's the dislocation is typically superotemporal whereas in the similar condition [[homocystinuria]], the dislocation is inferonasal.<ref name="mayo-gen">{{Cite web|url=http://www.mayoclinic.com/health/marfan-syndrome/DS00540/DSECTION=2|title=Marfan Syndrome|accessdate=January 12 2007|dateformat=mdy|publisher=Mayo Clinic}}</ref>
== [[Marfan's syndrome differential diagnosis|Differentiating Marfan's Syndrome from other Diseases]] ==


Sometimes eye problems appear only after the weakening of connective tissue has caused [[retinal detachment|detachment of the retina]].<ref name="mayo-gen">{{Cite web|url=http://www.mayoclinic.com/health/marfan-syndrome/DS00540/DSECTION=2|title=Marfan Syndrome|accessdate=January 12 2007|dateformat=mdy|publisher=Mayo Clinic}}</ref> Early onset [[glaucoma]] can be another related problem.
== [[Marfan's syndrome epidemiology and demographics|Epidemiology and Demographics]] ==
<br clear="left"/>


===Cardiovascular system===
== [[Marfan's syndrome screening|Screening]] ==


The most serious conditions associated with Marfan syndrome  involve the cardiovascular system. Undue fatigue, shortness of breath, [[heart palpitations]], [[tachycardia|racing heartbeats]], or [[Angina pectoris|pain in the left chest, back, shoulder, or arm]], can bring an individual into the doctor's office.  A [[heart murmur]] heard on a [[stethoscope]], an abnormal reading on an [[electrocardiogram]], or symptoms of [[Angina pectoris|angina]] can lead a doctor to order an [[echocardiogram]]. This can reveal signs of leakage or [[prolapse]] of the mitral or aortic [[heart valve|valves]] that control the flow of blood through the heart. (See [[mitral valve prolapse]].) However, the major sign that would lead a doctor to consider an underlying condition is a dilated aorta or an [[aortic aneurysm]].  Sometimes, no heart problems are apparent until the weakening of the connective tissue in the [[aorta|ascending aorta]] causes an [[aortic aneurysm]] or even [[aortic dissection]].
== [[Marfan's syndrome natural history, complications and prognosis|Natural History, Complications and Prognosis]] ==


Because of the underlying connective tissue abnormalities that cause Marfan syndrome, there is an increased incidence of dehiscence of prosthetic mitral valve.<ref name="Braunwald-2005">{{cite book | coauthors=Zipes, Libby Bonow Braunwald | title=Braunwald's Heart Disease ~ A Textbook of Cardiovascular Medicine, Seventh Edition | publisher=Elseview Saunders | date=2005 | location=United States of America | pages=1894 | id=ISBN 0-7216-0509-5}}</ref>  Care should be taken to attempt repair of damaged heart valves rather than replacement.
== Diagnosis ==


During pregnancy, even in the absence of preconceived cardiovascular abnormality, women with Marfan syndrome are at significant risk of acute [[aortic dissection]], which can be lethal if untreated. For this reason, women with Marfan syndrome should receive a thorough assessment prior to conception, and [[echocardiography]] should be performed every 6-10 weeks during pregnancy, to assess the aortic root diameter. Most women however tolerate pregnancy well and safe vaginal delivery is possible.<ref name="emed">{{Cite web|url=http://www.emedicine.com/ped/fulltopic/topic1372.htm#section~Miscellaneous|title=Marfan Syndrome, special concerns}}</ref>
[[Marfan's syndrome diagnostic criteria|Diagnostic Criteria]] | [[Marfan's syndrome history and symptoms|History and Symptoms]] | [[Marfan's syndrome physical examination|Physical Examination]] | [[Marfan's syndrome laboratory findings|Laboratory Findings]] | [[Marfan's syndrome electrocardiogram|ECG]] | [[Marfan's syndrome chest x ray|Chest X Ray]] | [[Marfan's syndrome CT|CT]] | [[Marfan's syndrome MRI|MRI]] | [[Marfan's syndrome echocardiography or ultrasound|Echocardiography ]] | [[Marfan's syndrome other imaging findings|Other Imaging Findings]] | [[Marfan's syndrome other diagnostic studies|Other Diagnostic Studies]]


*A typical aortic root in Marfan's syndrome.
== Treatment ==
<googlevideo>-760162053984535443&hl=en</googlevideo>


===Lungs===
[[Marfan's syndrome medical therapy|Medical Therapy]] | [[Marfan's syndrome surgery|Surgery]] | [[Marfan's syndrome primary prevention|Primary Prevention]]| [[Marfan's syndrome secondary prevention| Secondary Prevention]] | [[Marfan's syndrome cost-effectiveness of therapy| Cost-Effectiveness of Therapy]] | [[Marfan's syndrome future or investigational therapies|Future or Investigational Therapies]]


Marfan syndrome is a [[risk factor]] for spontaneous [[pneumothorax]].  In spontaneous unilateral pneumothorax, air escapes from a lung and occupies the [[pleural]] space between the chest wall and a [[lung]].  The lung becomes partially compressed or collapsed.  This can cause pain, shortness of breath, [[cyanosis]], and, if not treated, death.  Marfan syndrome has also been associated with [[sleep apnea]] and [[idiopathic]] obstructive lung disease.
== External links ==


===Central nervous system===
* [http://marfanworld.org/ International Federation of Marfan Syndrome Organisations]
 
* [http://www.marfan.org/ National Marfan Foundation (USA)]
Another condition that can reduce the quality of life for an individual, though not life-threatening, is [[dural ectasia]], the weakening of the connective tissue of the dural sac, the membrane that encases the [[spinal cord]]. 
* [http://www.ncbi.nlm.nih.gov/disease/Marfan.html National Institute for Health Marfan syndrome page (USA)]
 
Dural ectasia can be present for a long time without producing any noticeable symptoms.  Symptoms that can occur are lower [[back pain]], leg pain, [[abdominal pain]], other neurological symptoms in the lower extremities, or [[headaches]]. Such symptoms usually diminish when the individual lies flat on his or her back. 
 
These types of symptoms might lead a doctor to order an [[X-ray]] of the [[lumbar|lower spine]].  Dural ectasia is usually not visible on an X-ray in the early phases.  A worsening of symptoms and the lack of finding any other cause should eventually lead a doctor to order an upright [[MRI]] of the lower spine. 
 
Dural ectasia that has progressed to the point of causing these symptoms would appear in an upright MRI image as a dilated pouch that is wearing away at the [[lumbar vertebrae]].<ref name="mayo-gen" /> Other spinal issues associated with Marfan include degenerative disk disease and spinal cysts.
 
==Diagnosis==
 
Several standards of diagnostic criteria for Marfan syndrome have been proposed.  In 1986, the Berlin nosology was established which represented a consensus on clinical features diagnostic of Marfan syndrome with an emphasis on skeletal features <ref name="pmid3287925">{{cite journal |author=Beighton P, de Paepe A, Danks D, Finidori G, Gedde-Dahl T, Goodman R, Hall JG, Hollister DW, Horton W, McKusick VA |title=International Nosology of Heritable Disorders of Connective Tissue, Berlin, 1986 |journal=[[American Journal of Medical Genetics]] |volume=29 |issue=3 |pages=581–94 |year=1988 |month=March |pmid=3287925 |doi=10.1002/ajmg.1320290316 |url= |issn= |accessdate=2010-12-22}}</ref>.  Advances in molecular testing and the realization that many individuals diagnosed with Marfan syndrome according to the Berlin nosology did not have mutations in the FBN1 gene, led to the establishment of the Ghent nosology in1996, a new set of criteria with stricter diagnostic requirements <ref name="pmid8723076">{{cite journal |author=De Paepe A, Devereux RB, Dietz HC, Hennekam RC, Pyeritz RE |title=Revised diagnostic criteria for the Marfan syndrome |journal=[[American Journal of Medical Genetics]] |volume=62 |issue=4 |pages=417–26 |year=1996 |month=April |pmid=8723076 |doi=10.1002/(SICI)1096-8628(19960424)62:4<417::AID-AJMG15>3.0.CO;2-R |url= |issn= |accessdate=2010-12-22}}</ref>.  The Ghent nosology remains the current standard for diagnosis, although a revised version of the guidelines was published in 201015.  The criteria are divided into major and minor manifestations which have allowed physicians to correctly diagnose 95% of patients as confirmed by molecular analysis of the FBN1 gene <ref name="pmid20591885">{{cite journal |author=Loeys BL, Dietz HC, Braverman AC, Callewaert BL, De Backer J, Devereux RB, Hilhorst-Hofstee Y, Jondeau G, Faivre L, Milewicz DM, Pyeritz RE, Sponseller PD, Wordsworth P, De Paepe AM |title=The revised Ghent nosology for the Marfan syndrome |journal=[[Journal of Medical Genetics]] |volume=47 |issue=7 |pages=476–85 |year=2010 |month=July |pmid=20591885 |doi=10.1136/jmg.2009.072785 |url=http://jmg.bmj.com/cgi/pmidlookup?view=long&pmid=20591885 |issn= |accessdate=2010-12-22}}</ref>.  The new criteria establish aortic root aneurysm and ectopia lentis as the principal clinical features of the disease and stress cardiovascular manifestations. 
 
The major criteria for diagnosis of Marfan syndrome are ectopia lentis, aortic root dilation/dissection, dural ectasia, or a combination of more than 4 out of 8 major skeletal features (Table 1).  In an individual with no known family history of Marfan syndrome and in the absence of any known FBN1 mutations, major involvement of two organs systems (e.g. skeletal, cardiovascular, ocular) and minor involvement of a third system is required for diagnosis.  However, if the patient has a known FBN1 mutation or affected relative, major involvement of only one system and minor involvement of another is sufficient for diagnosis (Table 1).  Major manifestations of the cardiovascular system include ascending aortic dilation involving the sinuses of valsalva or dissection of the ascending aorta.  Ectopia Lentis is the sole major criterion for involvement of the ocular system, and dural ectasia in the lumbosacral region diagnosed by CT or MRI is the criterion for major involvement of the dura.  Having a known FBN1 mutation or a relative who independently satisfies criteria for diagnosis satisfies major involvement of family/genetic history.  Physical examination for Marfan syndrome requires extensive evaluation of the skeletal system.  Patients must fulfill four of the eight following criteria for major involvement of the skeletal system: pectus carinatum, pectus ex cavatum requiring surgery, reduced upper to lower segment ratio, wrist and thumb signs (Figure 1).  Minor criteria for the various systems including pulmonary and skin/integument can be found in the supplement.
 
{| class="wikitable" border="1"
|+ Diagnostic Criteria
! Skeletal System !!
|-
| Major Criterion. || Presence of at least '''4'''of the following manifestations.
• pectus carinatum
 
• pectus ex cavatum requiring surgery
 
• reduced upper to lower segment ratio or arm span to height ratio greater than 1.05
 
• wrist and thumb signs
 
• scoliosis of > 20" or spondylolisthesis
 
• reduced extension at the elbows (< 170")
 
• medial displacementof the medial malleolus causing pes planus protmsio acetabulae of any degree (ascertained on radiographs)
 
|-
| Minor criteria. ||
• pectus excavatum of moderate severity
 
• joint hypermobility
 
• highly arched palate with crowding of teeth
 
• facial appearance (dolichocephaly, malar hypo- plasia,enophthalmos,retrognathia,down-Slanting palpebral fissures)
 
|-
! Ocular System !!
|-
| Major criterion. || • Ectopia lentis
|-
|Minor criteria. ||
• abnormally flat cornea (as measured by keratometry)
 
• increased axial length of globe (as measured by ultrasound)
 
• hypoplastic iris or hypoplastic ciliary muscle causing decreased miosis
 
|-
! Cardiovascular System !!
|-
|Major criteria. ||
• dilatation of the ascending aorta with or without aortic regurgitation and involving at least the sinuses of Valsalva; or
 
• dissection of the ascending aorta
 
|-
|Minor criteria. ||
• Mitral valve prolapsed
 
• Mitral valve prolapsed with or without mitral valve regurgitation;
 
• dilatation of the main pulmonary artery, in the absence of valvular or peripheral pulmonic stenosis or any other obvious cause, below the age of 40 years;
 
• calcification of the mitral annulus below the age of 40 years; or dilatation or dissection of the descending thoracic or abdominal aorta below the age of 50 years
 
|-
! Pulmonary System !!
|-
|Minor criteria. ||
• spontaneous pneumothorax [Hall et al., 19841]
 
• apical blebs (ascertained by chest radiography)
 
|-
! Skin and Integument !!
|-
|Minor criteria. ||
• striaeatrophicae (stretchmarks) not associated with marked weight changes, pregnancy or repetitive stress
 
• recurrent or incisional herniae
 
|-
! Dura !!
|-
|Major criterion. ||
• Lumbosacral dural ectasia by CT or MRI
|-
! Family/Genetic History !!
|-
|Major criteria. || • having a parent, child or sib who meets these diagnostic criteria independently;
 
• presence of a mutation in FBNl known to cause the Marfan syndrome;
 
• presence of a haplotype around FBNl, inherited by descent, known to be associated with unequivocal- ly diagnosed Marfan syndrome in the family
 
|}
 
Adapted from De Paepe A, Devereux RB, Dietz HC, Hennekam RC, Pyeritz RE. Revised diagnostic criteria for the Marfan syndrome. Am J Med Genet 1996;62:417-26.
 
 
Molecular diagnostics, namely DNA sequencing can be extremely informative for the diagnosis of Marfan syndrome.  A 2008 study showed that while only 79% of known probands could be diagnosed with Marfan syndrome using clinical criteria, 90% of these individuals could be diagnosed using the international criteria when sequencing data was added.  In children, this figure leapt from 56% to 85% with sequencing data.  The increased diagnostic sensitivity conferred by genetic information promises to be especially useful in children who have not developed clinical manifestations, but in whom new pharmacological interventions may be successful.  Currently, laboratories offer complete sequencing of the 65 exon FBN1 gene for approximately $1700.00.  The high costs of these diagnostics have delayed the widespread use of molecular diagnostics in the approach to patients suspected of Marfan syndrome.  Increasingly less expensive sequencing technologies promise to increase reliance on individual genetic data for diagnosis in the future.
 
{| style="padding:0.3em; float:left; margin-left:5px; border:1px solid #A3B1BF;"
|-
|[[Image:Marfan pic1.jpeg|150px]]
|[[Image:Marfan pic2.jpeg|150px]]
|-
|<small> '''Image A:''' Skeletal exam of Marfan syndrome. Thumb sign, positive if the thumb protrudes from the clenched fist.</small>
|<small>'''Image B:''' Skeletal exam of Marfan syndrome. Wrist Sign, positive if thumb and first phalange can overlap when encircling wrist.</small>
<ref name="pmid11711445">{{cite journal |author=Cocco G |title=Images in cardiology: The "thumb and wrist sign" in Marfan syndrome |journal=[[Heart (British Cardiac Society)]] |volume=86 |issue=6 |pages=602 |year=2001 |month=December |pmid=11711445 |pmc=1730018 |doi= |url=http://heart.bmj.com/cgi/pmidlookup?view=long&pmid=11711445 |issn= |accessdate=2010-12-22}}</ref>
|}
{{clr}}
 
==Genetics==
 
Marfan syndrome is an autosomal dominant disorder caused by mutations in the Fibrillin-1 gene encoding an extracellular matrix protein which constitutes an essential component of microfibrils, critical in formation of elastin.  Engvall first isolated the protein from human fibroblast cell culture in 1986, demonstrated its function as a component of extracellular microfibrils and its widespread expression through connective tissue in many organ systems <ref name="pmid3536967">{{cite journal |author=Sakai LY, Keene DR, Engvall E |title=Fibrillin, a new 350-kD glycoprotein, is a component of extracellular microfibrils |journal=[[The Journal of Cell Biology]] |volume=103 |issue=6 Pt 1 |pages=2499–509 |year=1986 |month=December |pmid=3536967 |pmc=2114568 |doi= |url=http://www.jcb.org/cgi/pmidlookup?view=long&pmid=3536967 |issn= |accessdate=2010-12-22}}</ref>.  Early linkage studies of families with Marfan syndrome mapped the gene to 15q21.1 <ref name="pmid2402262">{{cite journal |author=Kainulainen K, Pulkkinen L, Savolainen A, Kaitila I, Peltonen L |title=Location on chromosome 15 of the gene defect causing Marfan syndrome |journal=[[The New England Journal of Medicine]] |volume=323 |issue=14 |pages=935–9 |year=1990 |month=October |pmid=2402262 |doi=10.1056/NEJM199010043231402 |url=http://dx.doi.org/10.1056/NEJM199010043231402 |issn= |accessdate=2010-12-22}}</ref>, surprising some investigators who suspected defects in the Elastin gene were causal.  Subsequent mutational analysis of FBN1 in patients with Marfan system revealed identical missense mutations in two unrelated patients9.  Many linkage studies have been performed and demonstrate that most families have private mutations.  The FBN1 gene is very large, consisting of 65 exons.  It encodes a 350 kiloDalton protein and is highly conserved between different species. 
 
Familial mutations of the FBN1 gene account for 75% of cases of Marfan syndrome and their corresponding phenotype is inherited in a dominant fashion.  Over 500 different FBN1 mutations have been detected in Marfan syndrome patients <ref name="pmid9399842">{{cite journal |author=Collod-Béroud G, Béroud C, Ades L, Black C, Boxer M, Brock DJ, Holman KJ, de Paepe A, Francke U, Grau U, Hayward C, Klein HG, Liu W, Nuytinck L, Peltonen L, Alvarez Perez AB, Rantamäki T, Junien C, Boileau C |title=Marfan Database (third edition): new mutations and new routines for the software |journal=[[Nucleic Acids Research]] |volume=26 |issue=1 |pages=229–3 |year=1998 |month=January |pmid=9399842 |pmc=147226 |doi= |url= |issn= |accessdate=2010-12-22}}</ref>.  56% of these mutations are missense mutations, most often by creating or substituting  a cysteine in a cbEGF domain critical for calcium binding <ref name="pmid21063442">{{cite journal |author=Hilhorst-Hofstee Y, Hamel BC, Verheij JB, Rijlaarsdam ME, Mancini GM, Cobben JM, Giroth C, Ruivenkamp CA, Hansson KB, Timmermans J, Moll HA, Breuning MH, Pals G |title=The clinical spectrum of complete FBN1 allele deletions |journal=[[European Journal of Human Genetics : EJHG]] |volume= |issue= |pages= |year=2010 |month=November |pmid=21063442 |doi=10.1038/ejhg.2010.174 |url=http://dx.doi.org/10.1038/ejhg.2010.174 |issn= |accessdate=2010-12-22}}</ref>.  Missense mutations are clustered in loci with cbEGF domains and typically cause moderate to severe phenotype <ref name="pmid8406497">{{cite journal |author=Dietz HC, McIntosh I, Sakai LY, Corson GM, Chalberg SC, Pyeritz RE, Francomano CA |title=Four novel FBN1 mutations: significance for mutant transcript level and EGF-like domain calcium binding in the pathogenesis of Marfan syndrome |journal=[[Genomics]] |volume=17 |issue=2 |pages=468–75 |year=1993 |month=August |pmid=8406497 |doi=10.1006/geno.1993.1349 |url=http://linkinghub.elsevier.com/retrieve/pii/S0888-7543(83)71349-2 |issn= |accessdate=2010-12-22}}</ref>.  Other documented mutations include nonsense, frameshift and splice site mutations.  Complete deletions of a FBN1 allele are very rare.  90% of FBN1 mutations are private to an individual or family10.  The incredibly diverse set of mutations that cause the syndrome suggest that these mutations generally reflect loss-of-function cause a dominant negative phenotype.  Haploinsufficiency and other theories have been proposed to account for the dominant negative phenomenon which will be detailed later.
 
No FBN1 mutation can be identified in 10% of Marfan syndrome patients.  In this subset of patients, mutations in the transforming growth factor-beta receptor 2 (TGFBR2) are causal.  Families with TGFBR2 mutations display autosomal dominant inheritance with variable penetrance. 
 
 
==Management==
 
There is no cure for Marfan syndrome, but life expectancy has increased significantly over the last few decades, and clinical trials are underway for a promising new treatment.<ref>Freeman, Elaine (2007) "[http://www.hopkinsmedicine.org/hmn/F07/feature1.cfm A Silver Bullet for Blake]", ''Johns Hopkins Magazine'', Fall, 2007.</ref> The syndrome is treated by addressing each issue as it arises, and, in particular, considering prophylactic medication, even for young children, to slow progression of aortic dilation.
 
Regular checkups by a [[cardiologist]] are needed to monitor the health of the heart valves and the aorta. The goal of treatment is to slow the progression of aortic dilation and damage to heart valves by eliminating [[Cardiac arrhythmia|arrythmias]], minimizing the [[heart rate]], and minimizing [[blood pressure]]. 
 
[[Beta blocker]]s have been used to control [[Cardiac arrhythmia|arrythmias]] and slow the [[heart rate]].  Other medications might be needed to further minimize [[blood pressure]] without slowing the [[heart rate]], such as [[ACE inhibitors]] and [[angiotensin II receptor antagonist]]s, also known as angiontensin receptor blockers (ARBs). 
 
If the dilation of the aorta progresses to a significant diameter [[aneurysm]], causes a dissection or a rupture, or leads to failure of the aortic or other valve, then surgery (possibly a composite aortic valve graft [CAVG] or valve-sparing procedure) becomes necessary. 
 
Although aortic graft surgery (or any vascular surgery) is a serious undertaking it is generally successful if undertaken on an elective basis. Surgery in the setting of acute aortic dissection or rupture is considerably more problematic. Elective aortic valve/graft surgery is usually considered when aortic root diameter reaches 50 millimetres, but each case needs to be specifically evaluated by a qualified cardiologist. New valve-sparing surgical techniques are becoming more common.<ref name="mayo-heart">{{Cite web|url=http://www.mayoclinic.org/marfan-syndrome/heartsurgery.html|title=Heart Surgery for Marfan Syndrome|publisher=Mayo Clinic}}</ref> As Marfan patients live longer, other vascular repairs are becoming more common, e.g. repairs of descending thoractic aortic aneurysms and aneurysms of vessels other than the aorta.
 
The skeletal and ocular manifestations of Marfan syndrome can also be serious, although not life-threatening. These symptoms are usually treated in the typical manner for the appropriate condition. This can also affect height, arm length, and life span.  The [[Nuss procedure]] is now being offered to people with Marfan syndrome to correct 'sunken chest' or ([[pectus excavatum]]).<ref name="chkd">{{Cite web|url=http://www.chkd.org/services/nussprocedure/Overview.aspx|title=Overview of the Nuss Procedure for Pectus Excavatum|publisher=Children's Hospital of The King's Daughters}}</ref> Because Marfan may cause spinal abnormalities that are asymptomatic, any spinal surgery contemplated on a Marfan patient should only follow detailed imaging and careful surgical planning, regardless of the indication for surgery.
 
Clinical trials have been conducted of the drug [[acetazolamide]] in the treatment of symptoms of [[dural ectasia]]. The treatment has demonstrated significant functional improvements in some sufferers.<ref name="spine">{{Cite web|url=http://www.spineuniverse.com/displayarticle.php/article922.html|title=Dural Ectasia in the Marfan Spine: Symptoms and Treatment|publisher=Scoliosis Research Society}}</ref> Other medical treatments, as well as physical therapy, are also available.
 
Treatment of a spontaneous [[pneumothorax]] is dependant on the volume of air in the pleural space and the natural progression of the individual's condition. A small pneumothorax might resolve without active treatment in 1 to 2 weeks.  Recurrent pneumothoraxes might require chest surgery. Moderately sized pneumothoraxes might need [[Chest tube|chest drain]] management for several days in hospital.  Large pneumothoraxes are likely to be medical emergencies requiring emergency decompression.
 
Research in laboratory mice has suggested that the [[angiotensin II receptor antagonist]] [[losartan]], which appears to block TGF-beta activity, can slow or halt the formation of aortic aneurysms in Marfan syndrome.<ref name="scimag">{{Cite journal | last = Habashi | first = Jennifer P. | coauthors = Daniel P. Judge, Tammy M. Holm, Ronald D. Cohn, Bart L. Loeys, Timothy K. Cooper, Loretha Myers, Erin C. Klein, Guosheng Liu, Carla Calvi, Megan Podowski, Enid R. Neptune, Marc K. Halushka, Djahida Bedja, Kathleen Gabrielson, Daniel B. Rifkin, Luca Carta, Francesco Ramirez, David L. Huso, and Harry C. Dietz | date = April 7, 2006 | title = Losartan, an AT1 Antagonist, Prevents Aortic Aneurysm in a Mouse Model of Marfan Syndrome | volume = 312 | issue = 5770 | pages = 117 - 121 | doi = 10.1126/science.1124287 | url = http://www.sciencemag.org/cgi/content/full/312/5770/117 | abstract = http://www.sciencemag.org/cgi/content/abstract/sci;312/5770/117 | news = http://www.news-medical.net/?id=17249}}</ref> A large [[clinical trial]] sponsored by the [[National Institutes of Health]] comparing the effects of losartan and [[atenolol]] on the aortas of Marfan patients is scheduled to begin in early 2007, coordinated by Johns Hopkins.<ref name="trial">{{Cite web|url=http://www.marfan.org/nmf/GetSubContentRequestHandler.do?sub_menu_item_content_id=147&menu_item_id=91|title=Atenolol vs. Losartan in Individuals with Marfan Syndrome Clinial Trial|publisher=National Marfan Foundation}}</ref>
 
Genetic counseling and specialized clinics are available at many academic medical centers for affected persons and family members.
 
==References==
{{reflist|2}}
 
==External links==
*[http://marfanworld.org/ International Federation of Marfan Syndrome Organisations]
*[http://www.marfan.org/ National Marfan Foundation (USA)]
*[http://www.marfan.org.za/diagnosis.html Marfan diagnosis criteria]
*[http://www.ncbi.nlm.nih.gov/disease/Marfan.html National Institute for Health Marfan syndrome page (USA)]
*[http://www.medicinenet.com/marfan_syndrome/index.htm Marfan Syndrome Center at medicinenet.com]
*[http://marfansyndrome.researchtoday.net/ Marfan Syndrome Research] - recent literature on Marfan Syndrome
*[http://www.supportmarfan.com Marfan support]
*[http://www.marfan.ca/ Canadian Marfan Association]
*[http://www.marfan.org.uk/ Marfan Association UK]
*[http://www.marfan.org.mx/ Marfan de Mexico]
*[http://www.marfan.no/ Norwegian Marfan Organization]
*[http://www.marfanlife.net Marfan Life blog] - mostly links to news articles about Marfan Syndrome
*[http://www.marfansyndrome.info MarfanSyndrome.Info] - Findings in Marfan Syndrome and link collection
*[http://www.marfanlife.net/lists/ Marfan-List] - email discussion list for people and families with Marfan Syndrome
*[http://www.marfan.org.za/ South African Marfan Syndrome Organisation] - support group for Africa
*[http://www.medstudents.com.br/original/revisao/marfan/marfan.htm Eye Findings in Marfan's syndrome]


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[[es:Síndrome de Marfan]]
[[fr:Syndrome de Marfan]]
[[ko:마르팡 증후군]]
[[it:Sindrome di Marfan]]
[[he:תסמונת מרפן]]
[[nl:Syndroom van Marfan]]
[[ja:マルファン症候群]]
[[nn:Marfans syndrom]]
[[pl:Zespół Marfana]]
[[pt:Síndrome de Marfan]]
[[ru:Синдром Марфана]]
[[sr:Марфанов синдром]]
[[fi:Marfanin oireyhtymä]]
[[sv:Marfans syndrom]]
[[uk:Синдром Марфана]]


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Latest revision as of 16:49, 3 November 2012

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Marfan syndrome
ICD-10 Q87.4
ICD-9 759.82
OMIM 154700
DiseasesDB 7845
MedlinePlus 000418
MeSH C17.300.500

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Editors-In-Chief: William James Gibson, C. Michael Gibson, M.S., M.D.; Associate Editor(s)-in-Chief: Cafer Zorkun, M.D., Ph.D. [1]; Assistant Editor-In-Chief: Cassandra Abueg, M.P.H. [2]

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Diagnostic Criteria | History and Symptoms | Physical Examination | Laboratory Findings | ECG | Chest X Ray | CT | MRI | Echocardiography | Other Imaging Findings | Other Diagnostic Studies

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