Smith–Kingsmore syndrome

Smith–Kingsmore syndrome is a rare genetic disorder that is caused by a gain-of-function mutation in a mTOR gene. The facial features of this syndrome are triangular face with a pointed chin, frontal bossing, hypertelorism, eyes with downslanting palpebral fissures, a flat nasal bridge, a long philtrum.

Presentation

The signs of this disease are:

Very frequent:

• Intellectual disability
• Macrocephaly

Frequent:

• Abnormal facial shape
• Abnormality of speech
• Curly hair
• Seizure
• Frontal bossing
• Ventriculomegaly

Occasional:

• Autistic Behaviour
• Cafe-au-lait spot
• Gait Disturbance
• Hypertelorism
• Hypotonia
• Open mouth
• Long philtrum
• Polymicrogyria
• Prominient forehead

Very rare:

• Downslanted palpebral fissures
• Depressed nasal bridge
• Decreased circulating IgA level

Cause

The cause of SKS is gain-of-function mutation in a gene MTOR.

This disease is inherited in autosomal dominant fashion, but most of the times it is de-novo mutation.

Diagnosis

SKS is a rare condition so many physicians aren't familiar with. A diagnosis of SKS is suspected based upon the identification of symptoms, a patient and family history and a thorough clinical evaluation.

SKS can be confirmed with the detection of a germline or mosaic mutation in the MTOR gene.

Frequency

Frequency of this disease is unknown, but all ethnic groups are equally affected.

Treatment

There is no cure for SKS, but management of some symptoms can be achieved.

History

SKS was first described by Dr Smith, L.D et al. in 2013.

References