Multiple Pterygium

Multiple pterygium Dr.V.Ravimohan http://www.mrcogexam.net

What is pterygium?
Pterygia are soft tissue webs across a joint or across the neck

When does it happen?
generalised association-Trisomies,Turner’s,Noonan’
specific syndrome-
popliteal pterygium
antecubital pterygium syndrome
multiple pterygium syndrome

specific syndrome
popliteal pterygium -popliteal web + facial anomalies
antecubital pterygium syndrome -web extending across the cubital fossa + anomalies of the radial head + radio-ulnar joint
multiple pterygium syndrome webbing of variable degrees involving the neck, axilla, elbow, knee and digits associated with short stature and orofacial anomalies.

multiple pterygium syndromes
phenotypically and genetically heterogeneous ( autosomal recessive , autosomal dominant or sporadic)
lethal and nonlethal (Escobar) types

nonlethal multiple pterygium syndrome(Escobar)
can be caused by mutation in the CHRNG gene, encoding the gamma subunit of the acetylcholine receptor (AChR).
Mutations in this gene can also cause the lethal variant of this phenotype

Escobar
Webbing of
neck
antecubital fossae
popliteal fossae
with sternal deformity and male hypogonadism
may behave sometimes as a dominant, but there clearly appears to be a recessive type

Escobar
multiple joint contractures with crouched stance and cleft palate
Males had small penis and scrotum and cryptorchidism
females had aplasia of the labia majora and small clitoris.

Skeletal anomalies
fusion of cervical vertebrae
scoliosis
flexion contraction of fingers
'rocker-bottom' feet with vertical talus

Clinical features
intrauterine death
congenital respiratory distress
short stature
faciocranial dysmorphism
ptosis
low-set ears
Arachnodactyly
cryptorchism in males

Escobar
first diagnostic sign is that of reduced fetal movement detected by ultrasound or reported by mothers.
At birth,
variable joint contractures
multiple pterygia
facial dysmorphism with long face, high-arched palate, small mouth, and retrognathism.

Escobar
Respiratory distress is a frequent life-threatening complication.
Later in life
patients frequently are affected by reduced muscular mass but do not show myasthenic symptoms
normal electromyelogram (EMG), except for unspecific indication of chronic myopathy.

Pathogenesis
mutations in the gamma, or fetal, subunit of the nicotinergic acetylcholine receptor
reduced fetal movements at sensitive times of development

CHRNG gene
encodes the gamma subunit of the AChR
expressed before the 33rd week of gestation in humans
replaced by the epsilon subunit in the late fetal and perinatal period, thereby forming the adult AChR.

AChRs have five subunits.
Two α, one β, and one δ subunit are always present.
By switching γ to subunits in late fetal development, fetal AChRs are gradually replaced by adult AChRs.

Other reasons for reduced fetal movements
Oligohydramnion
Drugs
metabolic conditions
neuromuscular disorders including myasthenia gravis

popliteal pterygium syndrome
Autosomal dominant with contractures limited to the knee
Repercussions that are only functional

popliteal pterygium syndrome
least 3 of the following deformities.
Cleft lip & palate
Popliteal pterygium
Paramedian lower lip sinuses
Genital anomalies
Dr.Sanjay Y.Parashar et al,.Spectrum of features in pterygium syndrome:Asian Journal of Surgery Vol 29:No 2 April 2006

MPS vs PPS
MPS -primary pathlogy ptergium
Facial and limb anomalies may be secondary to contracture
PPS-all the anomalies appear to be part of multisystem involvement
Dr.Sanjay Y.Parashar et al,.Spectrum of features in pterygium syndrome:Asian Journal of Surgery Vol 29:No 2 April 2006

MPS vs PPS Victor Escobar et al.Mutiple Pterygium sundrome:Am J Dis Child –Vol 132,June 1978 MPS PPS No Cleft lip/palate No Lip pits No sygnathia No Ankyloblepharon Absence of pterygia in neck/axillary region/antecubital fossa Autosomal recessive Autosomal dominant Cleft palate is present in 41% of cases Cleft lip(with or without cleft palate) present in nearly all cases

Frias' syndrome
Distinct form of the multiple pterygium syndrome with ptosis and skeletal anomalies.
Inheritance is autosomal dominant.
Jaime L. Frias, J. R. Holahan, A. L. Rosenbloom, A. H. Felman: An autosomal dominant syndrome of multiple pterygium, ptosis, and skeletal anomalities. Fourth International Conference on Birth Defects. Vienna 1973. Excerpta Medica, 19.

ESCOBAR vs Frias ESCOBAR Frias Arthrogryposis with pterygia Arthrogryposis with pterygia ptosis ptosis Antimongoloid slant of palperal fissures Antimongoloid slant of palperal fissures Scoliosis Scoliosis Always short stature Malsegmentation of spine

Management
Multidisciplinary team
Paediatrician
Physiotherapist
Orthopaedic surgeon

Multiple Pterygium

by Ravimohan Ravimohan on Dec 16, 2008

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Multiple Pterygium — Presentation Transcript