Interpretation of this PPD Test - 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 2 CK Forum

USMLE Step 2 CK Forum USMLE Step 2 CK Discussion Forum: Let's talk about anything related to USMLE Step 2 CK exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 07-04-2011
Ace3's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 735
Threads: 89
Thanked 289 Times in 191 Posts
Reputation: 301
Question Interpretation of this PPD Test

A 25-yr-old female develops positive PPD. The area of induration is 15mm at 48 h. A PPD test done 4 years earlier was negative. The patient has no past medical history. She has not received BCG vaccine. She has no fever, chills, night sweat, respiratory problem. Which best explains her PPD test?

a. patient does not have TB
b. patient has never had TB in the past
c. positive reaction is false positive due to non-tuberculous mycobacteria
d. patient is not a candidate for isoniazid prophylaxis
e. first positive test needs booster PPD
Reply With Quote Quick reply to this message



  #2  
Old 07-04-2011
Sadalssud's Avatar
USMLE Forums Addict
 
Steps History: 1 + CK
Posts: 132
Threads: 4
Thanked 107 Times in 62 Posts
Reputation: 117
Smile

I think that is E. Probably she was a false negative who required a second PPD. I am also thinking in C, but I have not read anything about it.

A and B : You have a positive PDD. Therefore she was exposed to Tb in the past.
C: It could be a possibility, however she has no history of previous non tb mycobacteria exposure. I
D: In fact, she is a candidate for prophylaxis if the CXR is negative.
Reply With Quote Quick reply to this message
  #3  
Old 07-04-2011
Ace3's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 735
Threads: 89
Thanked 289 Times in 191 Posts
Reputation: 301
Default

here answer is; false positive reaction due to nonmyco

a and b->positive ppd says a patient has or has had in past tb infection
d.patient needs isoniazid prophylaxis
e.a booster ppd is placed in 1 week after negative ppd in >55 yrs of age patients to boost up patients negative response.and negative booster test indicates patient is anergic or uninfected.
a ppd test is considered positive in following case:

>5mm: cxr showing healed tb, hiv or hiv at risk, close contact with a patient with active tb

>10mm: residents of nursing home,mental institution, prisoners, medically underserved, immigrants, iv drug abusers,persons with underlying disease

>15mm: all others
Reply With Quote Quick reply to this message
The above post was thanked by:
Sadalssud (07-04-2011)



Reply

Tags
Infectious-Diseases

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
Interpretation of PAP smear? kemoo USMLE Step 2 CK Forum 1 06-26-2011 01:56 AM
Coombs test (aka antiglobulin test or AGT) bebix USMLE Step 1 Bits & Pieces 0 06-08-2011 04:03 PM
Treatment vs control, the interpretation of the p-value bebix USMLE Step 1 Forum 5 05-26-2011 06:18 AM
The difference between Anterior Drawer Test and Lachman Test rasheed USMLE Step 2 CK Bits & Pieces 1 04-09-2011 07:21 AM
NBME Score Interpretation Rawalian USMLE Step 1 Forum 2 02-15-2011 03:05 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)