A Word About…..Those Beautiful Eyes
Ever wonder what results came from the 'does your child appear to sleep with his/her eyes open' question? This question was posed by Dr. Helga Toriello, a medical geneticist on KSN's Professional Advisory Group, to the members of the KSN email mailing list on March 16, 2000. The results of this survey and similar data was presented in August of this year at the 21st David W. Smith Workshop in San Diego, USA. About 40% of children with Kabuki (from the informal mailing list survey) are sleeping with eyes partially open, compared to about 5% in the general population.
A similar result was obtained in Holland with a show-of-hands poll. One mother noted that her daughter could not close her eyes. She would raise her cheeks when asked to close her eyes. It was remarked, at Holland's meeting, that some of the children with Kabuki have problems with eye infections when sleeping with eyes open.
It's suspected that the eyes may appear open because of the lower lid droop, so that some of the eye is visible, even though the child is asleep. This knowledge could become a helpful diagnostic tool. Further scientific studies are needed.
Also, of interest, is the article written about eye abnormalities:
Kabuki syndrome - Report of six cases and review of the literature with emphasis on ocular features - Ophthalmic Genetics Mar;21(1) pp. 51-61 2000 Author: Kluijt I, van Dorp DB, Kwee ML, Toutain A, Keppler-Noreuil K, Warburg M, Bitoun P.
The article highlights six patients diagnosed with Kabuki. All children had ocular (eye) abnormalities. The authors also studied past published articles of other patients with Kabuki. Of these, a total of 144 of 200 reported patients with KS had significant ocular abnormalities. This is in addition to the usual characteristic external ocular features such as long palpebral fissures and eversion of the lateral third of the eyelids. Most of the ocular abnormalities found are serious and cause visual impairment. In particular, blue sclerae (blue whites of the eye), strabismus (misalignment of the eyes), ptosis (drooping of the upper eye lid), and microphthalmia (abnormal smallness of the eyeballs) occur much more frequently in patients with KS than in the general population.
Kluijt et al. summarize the various inheritance theories of Kabuki. They speculate on why such a high percentage of patients with KS have such a variety of ocular anomalies.
Blue sclerae are seen in 58 different syndromes, mainly in syndromes with skeletal or connective tissue anomalies. Many features of Kabuki suggest a connective tissue defect. Connective tissue supports and connects internal organs, forms bones and the walls of blood vessels, attaches muscles to bones and replaces tissue of other types following injury. However, the authors speculate, most of the eye anomalies cannot be attributed to connective tissue defects alone. They suggest that some ocular defects may be due to ectodermal disorders, which have also been linked to Kabuki. Ectodermal disorders are caused by a defect in the formation of the outer layer of skin (ectoderm), casing certain anomalies of the skin, hair, nails, sweat glands, parts of the teeth, the lens of the eye, parts of the inner ear, nervous system, retina of the eye, and pigment cells. Kluijt et al. suggest that corneal opacities (cloudiness of the cornea, which is the 'window' of the eye) and obstructed nasolacrimal ducts may be due to an ectodermal disorder.
The authors strongly suggest that all people with Kabuki have an ophthalmological examination for early detection of ocular anomalies in order to prevent visual impairment.