Tests and diagnosis
By Mayo Clinic staffIn infants, signs that may prompt your doctor to request a blood test for Prader-Willi syndrome include:
- Poor muscle tone
- Almond-shaped eyes
- Narrowing of the head at the temples
In older children, your child's doctor may suspect Prader-Willi syndrome if your child exhibits:
- Behavioral problems
- Weight gain
A definitive diagnosis can almost always be made with a laboratory test. Special genetic tests can identify abnormalities in your child's chromosomes that are characteristic of Prader-Willi syndrome.
- Cassidy SB, et al. Prader-Willi syndrome. European Journal of Human Genetics. 2009;17:3.
- Prader-Willi syndrome. Genetics Home Reference. National Library of Medicine. http://ghr.nlm.nih.gov/condition/prader-willi-syndrome/show/print. Accessed Feb. 23, 2011.
- Scheimann AO. Clinical features, diagnosis, and treatment of Prader-Willi syndrome. http://www.uptodate.com/index.html. Accessed Feb. 15, 2011.
- McCandless SE, et al. Health Supervision for Children With Prader-Willi Syndrome. Pediatrics. 2011;127:195.
- Cassidy SB, et al. Prader-Willi Syndrome. In: Pagon RA, et al., eds. GeneReviews. Seattle, Wash.: University of Washington; 1993. http://www.ncbi.nlm.nih.gov/books/NBK1330/. Accessed Feb. 23, 2011.

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