What is Cretinism?
This occurs when the infant has been deprived of thyroid hormone either during prenatal life or babyhood. Developmental retardation, particularly of the bones and brain, is marked. The condition is common in regions where there is a severe iodine lack and endemic goitre is widespread. It is most likely that the mother of the affected child had goitre, and suffered from thyroid deficiency.
In some cases there is a congenital absence of the thyroid gland in the child. In some instances the infant may have been born to a parent who was under treatment for thyroid disease. The mother may have taken doses of thyroid-suppressing drugs in excess of her needs, and this has crossed into the womb during pregnancy, having a similar suppressing effect on the developing infant.
Typically the infant is drowsy, tends to go to sleep while feeding does not put on weight and show the normal rate of development and has a tendency to constipation. This may become evident in the first two or three months of life.
The abdomen tends to protrude, and often there is a swelling at the navel (umbilical hernia). The face shows a typical appearance, with a flattened nose, broad, puffy face, thick nostrils and lips and a tongue that protrudes. The skin is pale and dry. Pads of fat occur around the base of the neck, giving it a shortened look. The fontanelle (hole in the skull where the bones meet) tends to close later than normal, and the general bony development is much below normal. Mentally the infant is retarded, teeth are late in appearing, temperature is often below normal, hair is usually dark and the infant usually has a hoarse cry.
In areas where goitre is endemic, it is essential for the mother to take iodine as a prophylactic measure, otherwise there is a definite risk to her infant. After birth the child’s condition must be diagnosed early and accurately, and treatment started at once to avoid permanent mental and physical damage. However, if there has been a marked prenatal deficiency, by the time of birth adverse changes may have developed to the point of no return, and may be permanent despite any further treatment. In any event treatment is by the administration of thyroxine, and this will be worked out for the needs of the individual patient. The outlook will vary according to the degree of mental impairment that has occurred up to the time treatment is started.
Often no improvement will take place, and the child is an established cretin. The outlook then is extremely poor. In America hospitals now routinely screen newborn babies for thyroid deficiency. This enables very early diagnosis. Treatment is also started at once. About one baby in 4000 suffers from this problem.
It is likely that they will be diagnosed and best treated in the large endocrine clinics of major hospitals that have full facilities both for diagnosis and treatment.