nbme3/B4/Q42 - united123

[ArchivalUser]

42) A 4 year old boy is being evaluated for renal calculi. Urinalysis shows numerous hexagonally shaped crystals. Urine concentrations of several amino acids, including ornithine, arginine, and lysine, are increased. Which of the following is the most likely predominant component of the crystals?
A) Calcium oxalate
B) Cholesterol
C) Cysteine
D) Struvite
E) Uric acid


explain...

[ArchivalUser]

cystine crystals are hexagonal

this kid has cystinuria , an autosomal recessive disorder

[ArchivalUser]

c...transporter for cysteine, ornithine, lycine and arginine is defective

[ArchivalUser]

C is right

[ArchivalUser]

C.
Cystine stones
Caused by 4 amino acids = COLA
Cystiene
Orinthine
Lysine
Arginine
Envelope shaped crystals