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
An 8-month-old boy is brought to the physician by his parents for gradually increasing loss of neck control and inability to roll over for the past 2 months. During this time, he has had multiple episodes of unresponsiveness with a blank stare and fluttering of the eyelids. His parents state that he sometimes does not turn when called but gets startled by loud noises. He does not maintain eye contact. He was able to roll over from front to back at 5 months of age and has not yet begun to sit or crawl. His parents are of Ashkenazi Jewish descent. Neurological examination shows generalized hypotonia. Deep tendon reflexes are 3+ bilaterally. Plantar reflex shows extensor response bilaterally. Fundoscopy shows bright red macular spots bilaterally. The remainder of the examination shows no abnormalities. Which of the following is the most likely cause of this patient's symptoms?
ASphingomyelinase deficiency
Bβ-glucocerebrosidase deficiency
Cα-galactosidase A deficiency
DATP-binding cassette transporter mutation
Eβ-hexosaminidase A deficiency
An 18-month-old boy is brought to the physician because of a 2-day history of cough, fever, and lethargy. He has been admitted to the hospital twice during the past year for pneumonia. He can stand without support but has not started to walk. He speaks in bisyllables. He is at the 3rd percentile for height and 4th percentile for weight. Examination shows diffuse crackles over bilateral lung fields. Abdominal examination shows hepatosplenomegaly. Fundoscopy shows bright red macular spots. Despite being given appropriate antibiotic therapy, the patient dies. A photomicrograph of a section of the spleen obtained during autopsy is shown. Accumulation of which of the following substances is the most likely cause of this patient's condition?
ACeramide trihexoside
BCerebroside sulfate
CGlucocerebroside
DSphingomyelin
ELimit dextrin
+ 7 more in the PDF
Browse all chapters