Test your concepts - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 1 Forum

USMLE Step 1 Forum USMLE Step 1 Discussion Forum: Let's talk about anything related to USMLE Step 1 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 07-25-2014
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,109
Threads: 31
Thanked 521 Times in 394 Posts
Reputation: 540
Default Test your concepts

A newborn who is born at 38 weeks' gestation is brought to the emergency department because of recurring seizures. Further evaluation shows an inherited activating mutation in the calcium-sensing receptor in the parathyroid glands and kidneys. The PTH reference range for this laboratory is 10 - 65 pg/mL. Which of the following is most likely to be seen in laboratory studies?

Serum phosphorus (mg/dL) ( 1st column values)

Serum calcium (mg/dL) 2nd column values)

PTH (pg/mL) (3rd column values)

A. 6 .................................. 11 ............................... 100
B. 6 .............................. .... 2 .....................,,,,... 45
C. 6 ..................................... 2 ....,,...................,,,... 3
D. 2............... ...................... 11 ............................. 45
E. 2 ..................................... 11 ................................... 3
__________________
In USMLE, “Any fool can know. The point is to understand.”

Last edited by nsesereso; 07-25-2014 at 04:28 AM.
Reply With Quote Quick reply to this message



  #2  
Old 07-25-2014
Dr.ann's Avatar
USMLE Forums Addict
 
Steps History: Not yet
Posts: 156
Threads: 10
Thanked 49 Times in 30 Posts
Reputation: 59
Default

B
It could be secondary hyperparathyrodism
Reply With Quote Quick reply to this message
  #3  
Old 07-25-2014
Dr.ann's Avatar
USMLE Forums Addict
 
Steps History: Not yet
Posts: 156
Threads: 10
Thanked 49 Times in 30 Posts
Reputation: 59
Default

Or A
Reply With Quote Quick reply to this message
 
  #4  
Old 07-25-2014
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,109
Threads: 31
Thanked 521 Times in 394 Posts
Reputation: 540
Default

Which one are u taking A or B
__________________
In USMLE, “Any fool can know. The point is to understand.”
Reply With Quote Quick reply to this message
  #5  
Old 07-25-2014
Dr.ann's Avatar
USMLE Forums Addict
 
Steps History: Not yet
Posts: 156
Threads: 10
Thanked 49 Times in 30 Posts
Reputation: 59
Default

I m confused but i m gona choose B
Reply With Quote Quick reply to this message
  #6  
Old 07-25-2014
Dr.ann's Avatar
USMLE Forums Addict
 
Steps History: Not yet
Posts: 156
Threads: 10
Thanked 49 Times in 30 Posts
Reputation: 59
Default

So tell me the right answer?? Say its (B )PLZ LOL
Reply With Quote Quick reply to this message
  #7  
Old 07-25-2014
InRace's Avatar
USMLE Forums Scout
 
Steps History: Step 1 Only
Posts: 74
Threads: 20
Thanked 7 Times in 7 Posts
Reputation: 17
Send a message via Skype™ to InRace
Default

C. hypocalcemia, hypoparathyroidism


Quote:
Originally Posted by nsesereso View Post
A newborn who is born at 38 weeks' gestation is brought to the emergency department because of recurring seizures. Further evaluation shows an inherited activating mutation in the calcium-sensing receptor in the parathyroid glands and kidneys. The PTH reference range for this laboratory is 10 - 65 pg/mL. Which of the following is most likely to be seen in laboratory studies?

Serum phosphorus (mg/dL) ( 1st column values)

Serum calcium (mg/dL) 2nd column values)

PTH (pg/mL) (3rd column values)

A. 6 .................................. 11 ............................... 100
B. 6 .............................. .... 2 .....................,,,,... 45
C. 6 ..................................... 2 ....,,...................,,,... 3
D. 2............... ...................... 11 ............................. 45
E. 2 ..................................... 11 ................................... 3
Reply With Quote Quick reply to this message
  #8  
Old 07-25-2014
Dr.ann's Avatar
USMLE Forums Addict
 
Steps History: Not yet
Posts: 156
Threads: 10
Thanked 49 Times in 30 Posts
Reputation: 59
Default

Well it could be C but i get confuse with the kidney involvment..
A Now i m sure not will be the answer
Reply With Quote Quick reply to this message
  #9  
Old 07-25-2014
USMLE Forums Addict
 
Steps History: 1+CK+CS
Posts: 101
Threads: 2
Thanked 45 Times in 34 Posts
Reputation: 55
Default

i go with A
Reply With Quote Quick reply to this message
  #10  
Old 07-25-2014
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,109
Threads: 31
Thanked 521 Times in 394 Posts
Reputation: 540
Default

More answers pls. U guys should explain why u took those answers?
I will give the final answer though.
__________________
In USMLE, “Any fool can know. The point is to understand.”
Reply With Quote Quick reply to this message
  #11  
Old 07-25-2014
USMLE Forums Scout
 
Steps History: Step 1 Only
Posts: 61
Threads: 1
Thanked 123 Times in 31 Posts
Reputation: 133
Default

I would go with C since this mutation will cause the body to think calcium is high so PTH will drop. I know that an inactivating mutation in the receptor will yield familial hypercalcemic hypocalciuria so here i think the opposite will ocurr.
Reply With Quote Quick reply to this message
  #12  
Old 07-26-2014
USMLE Forums Scout
 
Steps History: Not yet
Posts: 16
Threads: 0
Thanked 2 Times in 2 Posts
Reputation: 12
Default

Quote:
Originally Posted by nsesereso View Post
A newborn who is born at 38 weeks' gestation is brought to the emergency department because of recurring seizures. Further evaluation shows an inherited activating mutation in the calcium-sensing receptor in the parathyroid glands and kidneys. The PTH reference range for this laboratory is 10 - 65 pg/mL. Which of the following is most likely to be seen in laboratory studies?

Serum phosphorus (mg/dL) ( 1st column values)

Serum calcium (mg/dL) 2nd column values)

PTH (pg/mL) (3rd column values)

A. 6 .................................. 11 ............................... 100
B. 6 .............................. .... 2 .....................,,,,... 45
C. 6 ..................................... 2 ....,,...................,,,... 3
D. 2............... ...................... 11 ............................. 45
E. 2 ..................................... 11 ................................... 3
C is the answer!! Activating mutations will decrease pth as it will sense there is too much calcium. It will then try to absorb phosphate bt serum calcium will be low
Reply With Quote Quick reply to this message
  #13  
Old 07-27-2014
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,109
Threads: 31
Thanked 521 Times in 394 Posts
Reputation: 540
Default

Ok guys the answer is C
__________________
In USMLE, “Any fool can know. The point is to understand.”
Reply With Quote Quick reply to this message
  #14  
Old 07-27-2014
USMLE Forums Scout
 
Steps History: Not yet
Posts: 16
Threads: 0
Thanked 2 Times in 2 Posts
Reputation: 12
Default Thanks

Thanks bro
Reply With Quote Quick reply to this message
  #15  
Old 07-27-2014
USMLE Forums Scout
 
Steps History: Step 1 Only
Posts: 61
Threads: 10
Thanked 13 Times in 11 Posts
Reputation: 23
Default

Quote:
Originally Posted by binav View Post
C is the answer!! Activating mutations will decrease pth as it will sense there is too much calcium. It will then try to absorb phosphate bt serum calcium will be low
would phosphate be elevated or normal? I would think normal because phosphate could only be elevated with Vit D ( which is PTH dependent) or due to renal failure... please explain your sentence regarding phosphate
Reply With Quote Quick reply to this message



  #16  
Old 07-27-2014
USMLE Forums Scout
 
Steps History: Not yet
Posts: 16
Threads: 0
Thanked 2 Times in 2 Posts
Reputation: 12
Default

Quote:
Originally Posted by USMLEgen View Post
would phosphate be elevated or normal? I would think normal because phosphate could only be elevated with Vit D ( which is PTH dependent) or due to renal failure... please explain your sentence regarding phosphate
Body tries to maintain product value of phisphate and calcium. So if the serum calcium is low and it cannot absorb calcium since pth is low the body would tey to bring the product value to normal by increasing the serum phosphate. So i guess phosphat must be high!!
Reply With Quote Quick reply to this message
The above post was thanked by:
USMLEgen (07-27-2014)



Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Medical School
Choose "---" if you don't want to tell. AMG for US & Canadian medical schools. IMG for all other medical schools.
USMLE Steps History
What steps finished! Example: 1+CK+CS+3 = Passed Step 1, Step 2 CK, Step 2 CS, and Step 3.

Choose "---" if you don't want to tell.

Favorite USMLE Books
What USMLE books you really think are useful. Leave blank if you don't want to tell.
Location
Where you live. Leave blank if you don't want to tell.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
CK Concepts Discussions olivegarden USMLE Step 2 CK Forum 22 12-17-2013 11:42 AM
FA Concepts enough for the exam? ddaydreamer USMLE Step 2 CS Forum 2 08-31-2013 10:14 AM
Concepts behind PEEP heartbeat USMLE Step 2 CK Forum 5 02-07-2013 10:42 AM
certain concepts sleepy USMLE Step 1 Forum 0 06-22-2012 03:26 AM
Tommy's HY concepts? Dr_Kal_El USMLE Step 1 Forum 2 03-22-2011 07:33 AM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)