Question

1. A 14-year-old male from Tondo, Leandro, was seen at the hospital because of delayed development. His mother recalls that when he turned 6 months old, he could not hold his head up when other babies aged 3 months old could do so. At age 13 months, his mother told the doctor that unlike other children of the same age, Leandro could not utter comprehensible words and could not walk. Upon further prodding by the doctor, the mother claimed that for the last few months, Leandro was having difficulty defecating and that his hair was scanty, coarse, and brittle prompting her to shave it anyway. The doctor then proceeded with his physical examination. He noted that Leandro had macroglossia, enlarged abdomen, and small for his age. At this point, the mother showed the doctor Leandro’s newborn screening result which confirmed the doctor’s diagnosis of congenital hypothyroidism.

a. Describe congenital hypothyroidism including its pathophysiology and relate it to Leandro’s physical findings and delayed development.
b. What could happen to Leandro if he is not managed properly?
c. Congenital hypothyroidism (CH) is part of the newborn screening (NBS) program of the Philippines. It is one of 6 disorders that are detected in the basic NBS kit. Enumerate the other 5 disorders detected in the NBS kit.
d. Enumerate the differences between the basic NBS kit and the newly introduced expanded NBS kit.
e. As a future medical technologist, are you allowed to perform newborn screening to a patient? If no, who else can perform it? If yes, which legal document authorizes you to perform the test?
f. Will you consider having your future child undergo newborn screening? If no, why not? If yes, which would you prefer, the basic or the expanded?

Answer 1

a. Describe congenital hypothyroidism including its pathophysiology and relate it to Leandro’s physical findings and delayed development.

Congenital hypothyroidism is the inborn error that can be caused by a missing, poorly formed, or abnormal thyroid gland developmental or biosynthesis disorders in newborn child. It could be due to the anatomic defect in the gland, an inborn error of thyroid metabolism, or iodine deficiency. The pathophysiology includes:

• Maternal hypothyroidism - cause mental retardation because maternal T3 / T4 crosses the placenta and is critical for fetal brain until the development of fetal thyroid gland.  \
• Two types of CH:

---> Thyroid dysgenesis (TD) - thyroid organogenesis defect.

---> Thyroid dyshormonogenesis - overall thyroid hormone synthesis.

b. What could happen to Leandro if he is not managed properly?

If Leandro is not managed properly, CH can lead to mental retardness, a constellation of physical and mental conditions, called cretinism. It also results in anemia, cold in extremities, intellectual disability, growth delays, loss of hearing and heart failure.

c. Congenital hypothyroidism (CH) is part of the newborn screening (NBS) program of the Philippines. It is one of 6 disorders that are detected in the basic NBS kit. Enumerate the other 5 disorders detected in the NBS kit.

6 disorders that are detected in the basic NBS kit disorders that are detected in the basic NBS kit:

• Congenital hypothyroidism (CH),
• Congenital adrenal hyperplasia (CAH),
• Phenylketonuria (PKU),
• Glucose-6- phosphate dehydrogenase (G6PD) deficiency,
• Galactosemia (GAL) and
• Maple syrup urine disease (MSUD).

d. Enumerate the differences between the basic NBS kit and the newly introduced expanded NBS kit.

The basic NBS kit purpose to screen newborn infants for inborn errors of metabolism (IEM) began about almost 5 decades ago with the insight of testing for phenylketonuria (PKU) . In the new NBS kit which was introduced in early decade of 2000, a new technology was introduced called tandem mass spectrometry (MS/MS) into the NBS arenas. It enable the simultaneous identification of various analytes using dried blood spots. Some of the newly added analysis in the advanced kit are: Homocystinuria, Citrullinemia, Argininosuccinic aciduria, Tyrosinemia etc.,