86
- What are the differences between endemic cretinism and sporadic congenital
hypothyroidism?
The differences between endemic cretinism and sporadic congenital
hypothyroidism are summarized in the table given below.
Parameters Endemic cretinismSporadic congenital
hypothyroidism
Prevalence 1:25–1:100 1:2500
Geographical area Iodine-defi cient areas Iodine-suffi cient area
Etiology Severe maternal–fetal iodine defi ciency Thyroid dysgenesis
Dyshormonogenesis
Clinical
presentationNeurological/myxedematous MyxedematousGoiter Present (neurological cretin) Usually absent
Absent (myxedematous cretin) Present in
dyshormonogenesis
Preventive
strategiesIodine supplementation –Therapy L-thyroxine (myxedematous cretin) L-Thyroxine
Rehabilitation (neurological cretin)- Why myxedematous manifestations are severe in endemic myxedematous cretin
as compared to sporadic congenital hypothyroidism in a neonate?
Myxedematous manifestations are severe in newborns with endemic myxede-
matous cretinism as compared to those with sporadic congenital hypothyroid-
ism at birth. This is because maternal T 4 (which is transferred to fetus during
intrauterine period) is suffi cient to prevent development of severe myxedema-
tous manifestations in those with sporadic congenital hypothyroidism, whereas
low maternal T 4 (due to severe iodine defi ciency) accounts for severe
myxedematous features in newborns with endemic myxedematous cretin. - What is endemic cretinism?
Endemic cretinism is characterized by irreversible mental disability in individ-
uals born in endemic iodine-defi cient regions and exhibit some or all of the
following features including; neuromuscular dysfunction (spasticity, motor
incoordination, and squint), deaf–mutism, impaired linear growth, and hypo-
thyroidism with or without goiter. Endemic cretinism occurs in regions where
intake of iodine is <25 μg/day.3 Thyroid Disorders in Children