PEDBASE.org - The Pediatric Database - Detailed information of XXXX SYNDROME

XXXX SYNDROME

DEFINITION:

A disorder where affected females have four X chromosomes.

EPIDEMIOLOGY:

incidence: rare, about 40 cases reported
age of onset:
- childhood
risk factors:
- females only

PATHOGENESIS:

1. Background

first described by D.H. Carr, M.L. Barr, and E.R. Plunkett, Can. Med. Assoc. J. 84:131 (1961).
also called Chromosome X, Poly-X

2. Pathogenesis

due to successive nondisjunctive meiotic divisions within a parent
the XXXX Syndrome phenotype is quite variable with some patients having facies suggestive of Trisomy 21

CLINICAL FEATURES:

1. Dysmorphisms

hypertelorism
upward slanting palpebral fissures
epicanthal folds
midfacial hypoplasia
micrognathia
normal to tall stature
narrow shoulder girdle
5th finger clinodactyly
simian crease

2. Neurological Manifestations

IQ ranges from 30-50 with a mean of 55
speech and language delays
behavioural problems

3. Endocrine Manifestations

incomplete or absent sexual development
variable amenorrhea with irregular menses
may be some fertility problems

4. Other Manifestations

congenital heart disease
radioulnar synostosis

INVESTIGATIONS:

1. Karyotype

48, XXXX karyotype

MANAGEMENT:

1. Supportive

Paediatrics, Endocrinology, Neurology, Psychology
genetic counselling
supplemental teaching for poor school performance

ADDITIONAL REFERENCES:

1. Jones, K.L., Smith's Recognizable Patterns of Human Malformation (5th Edition). p. 80. (1997).

2. Baraitser, M. and R.M. Winter, Color Atlas of Congenital Malformation Syndromes (1st Edition). p. 13. (1996).

Pediatric Database - XXXX SYNDROME

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