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Discussion Starter · #1 ·
A 22-year-old develops chronic abdominal pain and hematuria. A sample of the patient's urine reveals small stones which are shown here under a microscope.
urine stone_crystal.jpg
click to enlarge

This individual most likely has a metabolic disorder characterized by:
A. Sex linked dominant
B. Sex linked recessive
C. Autosomal recessive
D. Autosomal dominant
E. Chromosomal translocation

In the above patient, treatment for the kidney stone can be initiated by :
A. Antibiotics
B. Increasing protein rich diet
C. Increasing vitamin C in diet
D. Potassium citrate medication
E. Decreasing milk consumption
 
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hexagonal crystals so most probably cystein stones...which precipitate in acidic urine...req. alkalisation of urine...
C. Autosomal recessive
D. Potassium citrate medication
 

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Discussion Starter · #3 ·
yep right!!!

the correct answer is C.
Hexagonal-shaped crystals are usually composed of cystine. Patients with cystine kidney stones almost always have cystinuria, an autosomal recessive metabolic disorder. The mutation involves a transporter protein, which prevents reabsorption of positively charged amino acids such as cysteine.
The correct answer is D.
Cystine crystals will precipitate if the urine pH is neutral or acidic. Alternatively, alkalization of urine will decrease cystine crystal formations. This can be completed by administering drugs such as potassium citrate, sodium bicarbonate, and acetazolamide. Acidification of urine by NH4Cl, vitamin C, or cranberry juice will facilitate formation of these crystals. A protein rich diet may also worsen the condition due to increased amino acid formation.
 
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