 Welcome to day 18 of our 30 day pants review series where we pick a notecard at random and help you study for the pants So today's notecard is PPD Interpretation otherwise known as the Manto test interpretation. That's where you get the little bleb the little little bubble Intradermal in your forearm usually and then you come back 48 hours to 36 hours Sorry 48 hours to 72 hours later and you get that interpreted and if it's red and indurated You know that it's a it's a positive depending on the size and if it's not then it's negative depending again on the size So that's a test you'll commonly see as a provider in your primary care office in your urgent care In your occupational medicine practices if you work in any of those But you need to know it for the pants and for your exam anyway, so you may as well learn it So ppd interpretation there are three sizes that you have to worry about three sizes of induration And i'm going to give you a few seconds to think about those three sizes and what they mean So ppd interpretation give me three different sizes of the possible area of induration and what it could mean okay Size number one is going to be over 15 millimeters. So over 15 millimeters of induration means a positive test a positive ppd for a low risk patient someone who does not work in health care Someone who is not homeless someone who is not an immigrant to the united states from an area where tuberculosis is endemic and someone who does not have history of IV drug abuse IV da sorry my handwriting is terrible on the snow card so again High risk is someone who is health care worker who was an immigrant from a country that has Tuberculosis is an endemic someone who is homeless someone who was an IV drug abuser Those are all high risk. So the first of the three sizes is 15 millimeters or more 15 millimeters or more of induration Following the tuberculosis test. It's positive for low risk patients That is patients that are not in any of those categories that i just told you about size number two Is going to be more than 10 millimeters and that is a positive test for anybody that is in one of those categories And then size number three is more than five millimeters and more than five millimeters is a positive test for someone who is immunocompromised Has a positive chest x-ray has recent steroid use or has recently Contacted somebody who is known positive for TB. So the way you could think about this is it's basically three different sizes for three different groups of people The first one the least um or better yet the The least restrictive the one that's the hardest to become positive is for low risk individuals People who do not fit into any of these categories of high risk individuals You have to be 15 millimeters or greater of induration to test positive on the t beats reading test The second group is folks who are high risk quote-unquote, uh, or I guess we can call a moderate risk And those people need more than a 10 millimeter Induration so smaller than the 15 10 millimeters of induration is positive for anyone who is a health care worker like myself Someone who is an immigrant from a country where there is, uh, tuberculosis is endemic Someone who is homeless or someone who has a history of IV drug abuse and then finally five millimeters the most The easiest way to test positive for TB is for the ultra high risk group Or I guess you can call it the high risk group and that is going to be the people who are immunocompromised So they have hiv aids. They are on an immunosuppressant something like that. They have a positive chest x-ray they have characteristic hyalur What is the hyalur masses or I forget what it's actually called But a positive chest x-ray indicating TB if that is positive and there are more than five millimeters. They are positive uh, recent steroid use which is sort of kind of uh, like being immunocompromised Because it's an immunosuppressant and also if they recently had a positive TB contact All they need is five millimeters of induration to be tested positive for TB