Archive Of Standardized Exam Questions: Cystinuria

OVERVIEW

This page is dedicated to organizing various examples of standardized exam questions whose topic is cystinuria. While this may seem a odd practice, it is useful to see multiple examples of how cystinuria will be characterized on standardized exams (namely the boards and the shelf exams). This page is not meant to be used as a traditional question bank (as all of the answers will be the same), however seeing the classic “test” characterization for a topic is quite valuable.

KEY CHARACTERISTICS OF THIS CONDITION (ON EXAMS)

When it comes to standardized exams, each topic has its own “code” marked by key buzzwords, lab findings, clues, etc. If you are well versed in this code you will be able to more quickly identify the condition that is being discussed, and get the right answer on the exam you are taking. Below is the “code” for cystinuria

  • Re-current nephrolithiasis: flat, yellow hexagonal stones are seen microscopically. 
QUESTION EXAMPLES

Question # 1

 

Explanation # 1

 

Question # 2

 

Explanation # 2

 

TESTABLE FACTS ABOUT THIS TOPIC (BEYOND ITS IDENTIFICATION)

Many questions on standardized exams go beyond simply recognizing the underlying topic. Often there are specific testable facts regarding some aspect of the topic’s pathophysiology/management/clinical implications that are commonly asked. Some of these are listed below:

  • Inheritance pattern: autosomal recessive 
  • Cause: the transporter for the dibasic amino acids is defective.  
    • COLA acronym (dibasic amino acids): cysteine, ornithine, lysine, and arginine 
  • Consequencesimpaired renal/intestinal absorption of the dibasic amino acids.
    • DOES NOT cause amino acid deficiencies, because these amino acids are absorbed in appropriate amounts in the form of oligopeptides. 
    • In the kidneys cystine stones develop: the other amino acids are relatively soluble and do not precipitate.  
  • Treatment:
    • Hydration: useful for any type of nephrolithiasis 
    • Urinary alkalization: using acetazolamide

 

 

Page Updated: 04.24.2017