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- Which growth chart should be used for monitoring linear growth in children
with TS?
The height of a girl with TS should be plotted on TS-specific growth charts as
well as standard growth charts. Monitoring of growth on standard growth charts
is important as it allows early detection of growth abnormalities and timely
initiation of rhGH therapy. In addition, a girl with TS should also be monitored
on TS-specific growth chart, and if the height of the child falters on TS-specific
growth chart (either crosses centile curve downward or height ≤ –2SDS), sec-
ondary causes of growth retardation like hypothyroidism, celiac disease, mal-
nutrition, or growth hormone deficiency should be actively sought.- What are the alterations in growth hormone dynamics in TS?
The data regarding GH-IGF1 axis in patients with TS is conflicting. Most of the
studies show that integrated GH secretion is normal during prepubertal years,
while it is low during peripubertal period. This is because of lack of pubertal
GH surge in these patients due to estrogen deficiency and when treated with
estrogen, GH secretion is normalized. GH response to provocative stimuli is
also normal in majority of patients with TS, while 10–20 % of these patients
may have coexisting GH deficiency. Serum IGF1 levels have been reported to
be normal or low in various studies. Low IGF1 has been attributed to GH resis-
tance at hepatocytes, decreased acid-labile subunit, and increased IGFBP3 pro-
teolysis. Some studies have also reported IGF1 resistance in girls with TS.- What are the otological disorders in children with TS?
Abnormalities of external, middle, and inner ear are common in patients with
TS. The external ear abnormalities include low-set ears, abnormal downward slop-
ping of the helix, and upward slanting of external auditory canals. Abnormalities
of middle ear predispose children with TS to recurrent and bilateral suppurative
otitis media (SOM). This is due to malalignment of eustachian tube to middle ear
as a result of abnormal skull base anatomy, persistent lymphatic effusion due to
lymphatic hypoplasia, and hypotonia of tensor palati muscles. Recurrent episodes
of otitis media result in scarring of tympanic membrane and subsequent conductive
hearing loss (CHL). This is usually nonprogressive and resolves with advancing
age due to growth of facial structures. The inner ear abnormality manifests as sen-
sorineural hearing loss (SNHL), classically at a frequency of 1.5–2 KHz or above
8 KHz. This is due to reduced sensory cells in cochlea. SNHL typically manifests
during adulthood and is progressive, unlike CHL, which presents in childhood and
resolves with time. Otological disorders are attributed to SHOX haploinsufficiency,
as SHOX gene is expressed in first and second pharyngeal arches which develop
into maxilla, mandible, ear ossicles, and muscles of soft palate.8 Turner Syndrome