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A 5-month-old boy is brought to his pediatrician because his parents have noticed that he has very restricted joint movement. He was born at home without prenatal care, but they say that he appeared healthy at birth. Since then, they say that he doesn't seem to move very much and is hard to arouse. Physical exam reveals coarse facial structures and hepatosplenomegaly. Radiography reveals skeletal malformations, and serum tests show high plasma levels of lysosomal enzymes. The production of which of the following substances will most likely be disrupted in this patient?
AGlucocerebroside
BMannose-6-phosphate
CHeparan sulfate
DCeramide
You examine an infant in your office. On exam you observe hypotonia, as well as the findings shown in Figures A and B. You order laboratory testing, which demonstrates the findings shown in Figure C. Which of the following is the most likely pathologic mechanism involved?
AAccumulation of galactocerebroside
BAccumulation of ceramide trihexoside
CAccumulation of GM2 ganglioside
DAccumulation of glucocerebroside
EAccumulation of sphingomyelin
A 7-month-old boy is brought by his parents to the pediatrician’s office. His mother says the child has been weakening progressively and is not as active as he used to be when he was born. His condition seems to be getting worse, especially over the last month. He was born at 41 weeks through normal vaginal delivery. There were no complications observed during the prenatal period. He was progressing well over the 1st few months and achieving the appropriate milestones. On examination, his abdomen appears soft with no liver enlargement. The patient appears to be dehydrated and lethargic. The results of a fundoscopic examination are shown in the picture. A blood test for which of the following enzymes is the next best assay to evaluate this patient's health?
AAcid alpha-glucosidase
BHexosaminidase
CSphingomyelinase
DGlucocerebrosidase
EArylsulfatase A
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