left Diagnostic criteria of<unk>  were agreed upon internationally in 1996. However,<unk>  is often difficult to diagnose in children, as they typically do not show symptoms until reaching pubescence. A diagnosis is based on family history and a combination of major and minor indicators of the disorder, rare in the general population, that occur in one individualfor example: four skeletal signs with one or more signs in another body system such as ocular and cardiovascular in one individual. The following conditions may result from<unk> , but may also occur in people without any known underlying disorder. * Aortic aneurysm or dilation * Arachnodactyly * GERD * Bicuspid aortic valve * Cysts * Cystic medial necrosis * Degenerative disk disease * Deviated septum * Dural ectasia * Early cataracts * Early glaucoma * Early osteoarthritis * Ectopia lentis * Emphysema * Iris coloboma * Above-average height * Heart palpitations * Hernias * High-arched palate * Hypermobility of the joints * Kyphosis (hunched back) * Leaky heart valve * Malocclusion * Micrognathia (small lower jaw) * Mitral valve prolapse * Myopia (nearsightedness) * Obstructive lung disease * Osteopenia (low bone density) * Pectus carinatum or excavatum * Pes planus (flat feet) * Pneumothorax (collapsed lung) * Retinal detachment * Scoliosis * Sleep apnea * Stretch marks not from pregnancy or obesity * Teeth crowded * "Narrow, thin face" * Temporomandibular joint dysfunction (TMD) Revised Ghent nosology Thumb sign; upper: normal, lower:<unk>  In 2010, the Ghent nosology was revised, and new diagnostic criteria superseded the previous agreement made in 1996. The seven new criteria can lead to a diagnosis: In the absence of a family history of<unk> : # Aortic root Z-score ≥ 2 AND ectopia lentis # Aortic root Z-score ≥ 2 AND an FBN1 mutation # Aortic root Z-score ≥ 2 AND a systemic score* > 7 points # Ectopia lentis AND an FBN1 mutation with known aortic pathology In the presence of a family history of<unk>  (as defined above): # Ectopia lentis # Systemic score* ≥ 7 # Aortic root Z-score ≥ 2 * Points for systemic score: * Wrist AND thumb sign = 3 (wrist OR thumb sign = 1) * Pectus carinatum deformity = 2 (pectus excavatum or chest asymmetry = 1) * Hindfoot deformity = 2 (plain pes planus = 1) * Dural ectasia = 2 * Protrusio acetabuli = 2 * pneumothorax = 2 * Reduced upper segment/lower segment ratio AND increased arm/height AND no severe scoliosis = 1 * Scoliosis or thoracolumbar kyphosis = 1 * Reduced elbow extension = 1 * Facial features (3/5) = 1 (dolichocephaly, enophthalmos, downslanting palpebral fissures, malar hypoplasia, retrognathia) * Skin striae (stretch marks) = 1 * Myopia > 3 diopters = 1 * Mitral valve prolapse = 1 The thumb sign (Steinberg's sign) is elicited by asking the person to flex the thumb as far as possible and then close the fingers over it. A positive thumb sign is where the entire distal phalanx is visible beyond the ulnar border of the hand, caused by a combination of hypermobility of the thumb as well as a thumb which is longer than usual. The wrist sign (Walker-Murdoch sign) is elicited by asking the person to curl the thumb and fingers of one hand around the other wrist. A positive wrist sign is where the little finger and the thumb overlap, caused by a combination of thin wrists and long fingers. Differential diagnosis Many other disorders can produce the same type of body characteristics as<unk> . Genetic testing and evaluating other signs and symptoms can help to differentiate these. The following are some of the disorders that can manifest as<unk> oid": * Congenital contractural arachnodactyly, also known as Beals-Hecht syndrome * Ehlers–Danlos syndrome * Homocystinuria * Loeys–Dietz syndrome * MASS phenotype * Multiple endocrine neoplasia, type 2B * Shprintzen–Goldberg syndrome * Stickler syndrome
Marfan syndrome
Ehlers–Danlos syndromes
Marfanoid
Loeys–Dietz syndrome
Andersen–Tawil syndrome
Laron syndrome
XYY syndrome
Flynn–Aird syndrome