Pallister-Hall Syndrome (GLI3)

Clinical Features

Pallister-Hall syndrome (PHS) is characterized by postaxial polydactyly and hypothalamic hamartoma (Johnston et al. 2010. PubMed ID: 20672375). Additional features include: gelastic seizures, small nails, imperforate anus, bifid epiglottis, and laryngotracheal clefts. PHS patients may have pituitary insufficiency, which can result in death from adrenal insufficiency. Symptoms are variable in appearance and severity. Inter-familial variability has been reported to be much greater than intra-familial variability.


Managing clinical symptoms is critical for patients with Pallister-Hall syndrome (Kuo et al. 1999. PubMed ID: 10588106).

Identification and Treatment of Endocrine Abnormalities

Studies on children diagnosed with PHS have shown that administering growth hormone therapy at a young age was successful in achieving normal height (Galasso et al. 2001. PubMed ID: 11241471). Urgent treatment for endocrine abnormalities in PHS patients is highly recommended to prevent mortality (Biesecker, L. 2000. PubMed ID: 20301638).

Preventing Seizures

Some stimulant medications such as those used for Attention Deficit Hyperactivity Disorder should be avoided if possible as they may exacerbate seizures in affected individuals (Biesecker, L. 2000. PubMed ID: 20301638).

Airway Management

Urgent evaluation by an otolaryngologist for laryngotracheal cleft is indicated when signs or symptoms of aspiration are present (Biesecker, L. 2000. PubMed ID: 20301638).

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This article is a summary of information that has been reported in the biomedical research literature. It is not medical advice for patients. All disease treatments should be under the direction of a qualified healthcare provider.

Last Updated: 4/23/2018