A 5-Month-Old Boy Is Brought to the Office Due to Poor

question 8

Multiple Choice

A 5-month-old boy is brought to the office due to poor feeding.  His mother says that he has difficulty holding his head up while breastfeeding and his suckling seems weaker than usual.  Weight is at the 5th percentile.  Length and head circumference are tracking along the 25th percentile.  Physical examination shows hepatomegaly and hypotonia in all 4 limbs.  Cardiac auscultation shows a gallop rhythm, and chest x-ray reveals severe cardiomegaly.  Muscle biopsy shows enlarged lysosomes containing periodic acid-Schiff (PAS) -positive material.  Which of the following enzymes is most likely deficient in this patient?

• A)Acid alpha-glucosidase
• B)Galactokinase
• C)Glucose-6-phosphatase
• D)Glycogen debrancher enzyme
• E)Glycogen phosphorylase
• F)Pyruvate kinase

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Definitions:

Monolingual

A person or system capable of using or understanding only one language.

Symbolic Structure

Internal and external systems of symbols, signs, and meanings that guide and structure human communication and understanding.

Morpheme Structure

The arrangement and composition of morphemes, which are the smallest grammatical units in a language, contributing to semantic meaning.

Semantics

The study of meaning in language, including the meanings of words, phrases, and sentences.