Mantoux Test (aka. PPD or TST)

Find out how the Mantoux test helps us to distinguish between individuals who have and have not been exposed to TB in the past. Rishi is a pediatric infectious disease physician and works at Khan Academy.
These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

[@SarahBrown-wh9th]

Who’s here after they got a TB test?

[@mxolisisigodi5817]

We are studying to cure you wena

[@sagar-cf4tn]

Great I am very scared after my ppd test now I am happy😊😊😊 thank you a lot for giving information 🙏🙏

[@theadenirans4654]

Thank you for your detailed explanation. I understood how it works now. 😊 My 2 son just done Matoux test.

[@Sandra-rs8sv]

Thank you!!! Very well explained.

[@KathLifestyle]

Best explanation than others thank you!!

[@jo22xtian]

great stuff... thank you!

[@kidskorner6216]

Thank you so much, that was very helpful

[@karenjoycebustillo6893]

Thank you, this is very helpful!

[@tunkuintannabilah]

thank you so much.this sure will help me in the upcoming exams : )

[@eclkt]

Thank you for your education.

[@06Satorare]

Clear explanations. Thanks.

[@fabm4252]

Very informative thank you.

[@maitrivaria5930]

8.34 is really worth spending........ Thank you so much for making this easy for us.

[@sunithkumarapperuma3952]

Thank you sir for excellent explanation

[@user-ld3bh3wp8s]

Very good explanation, thanks

[@napoleonparasdas9328]

very good explanation thanks very much

[@nirupamakumar622]

nice explanations....thank u

[@user-mr3iv7bj6n]

wooo its really great dr thank u so much

[@sw-xs6sk]

The exact principle mechanism I was looking for Thnx

[@neishawilliams544]

Excellent animation!

[@natedogfresh]

Excellent information.

[@jyothisekhar8556]

Thank you sir...nice and clear explanation

[@panagwoman7398]

you are so awesome ..i guess in just a paranoid mommy but my son is 15 mths n he has got a tb test yesterday and im just freaking myself out on web md.lol. well its because the lady that gave my son the shot didn't explain anything really she just told me when to return..so with that being said your video helped lots ...and his arm is a little red where the needle went in but it is flat....i guess its just hard bein a loving parent...i guess ill be a ease when i get the ok from doc.. but thanks for your knowledge on this part...

[@MrC72k]

I doubt you were able to understand this video

[@yuganthiireshakalinga3954]

Valuable stuff!!!

[@HafizahHoshni]

Simply superb!! Makes learning beautiful and easy 9/8/2018 ❤

[@maimwatenga9895]

Brilliant explanation

[@esababbiie]

Very helpful Thanks

[@omamahabdullah1440]

Thank you.

[@mannynpris]

you are amazing i love your videos

[@PTCHYOLO]

thanks for the learning! =)

[@dhwanishah5869]

Thxs.. U r my saviour 😊😊😊😊

[@satheeshkumar6694]

Very useful video

[@reyanshsharma172]

Very well explained love it 😊

[@MrMdbling]

thank you

[@vetaya4783]

Thank you :))

[@marishapeter1267]

Thankyou sir for your information...it's very easy to understand..

[@itsFrancis254]

Great explanation ✔️👍

[@rubixfilms687]

So I recently started a job at a jail and was randomly called to the nurses office on my first day and she told me that I had to get one of those. And she would check on the bump a couple days later. I was kinda confused by it because I had never been tested for it. So that's why I'm here lol. Explained allot.

[@cerinacapone7945]

can you please tell me if it hurt or not. i have to get this done for college and i have a severe anxiety disorder

[@rubixfilms687]

@@cerinacapone7945 wow this was seven months ago lol. I'm still at the jail. And no it didn't hurt at all lol.

[@luckylondon8291]

@@rubixfilms687what if it got positive ? Does that mean you have TB or how to cure it ? Bcz today or tmmrw Simone can catch the virus due to working at such place like hospital or nursing home

[@InnocentIkoedem-di6mo]

Thank you very much, sir.

[@arunkumars6257]

Thank you so much.

[@neelesh_tripathi]

Thank you

[@aldridgefoster9882]

Thnkq so much...

[@saikumar802]

Tq ur awesome ur lessons r so clear it is very helpfull to me 1nce again tq so much........

[@saikumar802]

long live khan academy.........

[@afrodisiaque8706]

Must the injected site have a “bubble” to know if the test has been administered properly?

[@zainaki4857]

Thanks alot 🌸

[@obsakedir4068]

thanks so much

[@pedrobertulino]

Super cool

[@yogeshwarisingh1216]

Thank you so much and

[@mahmoudtarek167]

thanks!

[@Ink_Quanta]

Nice 🎉

[@kishoresontyana8837]

Thank u sir😊

[@rozschndr9014]

AAAAAHHHHHWESOMEEEEEE!!! My PPD test it's FLATTTTT!

[@kenshin9880ify]

awesome

[@shielladalangin6934]

hi just want to ask after the skin test when will be disappear the redness/hardened of the skin?

[@me4077]

Great explanation.☺️.but the thing that can't cross my mind is ppd(--).I mean ,how come Tcell never seen a strange object like that and did not attack it??

[@swiss3072]

I just had this today

[@ranjanasahu7740]

I am 15 and I just got this test.

[@paulette709]

Great video! I was just wondering what's the name of the program you used to make this video? Does anyone know?

[@shivanisingh7964]

Its for TB disease

[@spandankaushik14]

Just wondering, if the same person goes for a TCT/PPD test for the second time, would he show positive results due to the first PPD generating memory of the encounter??

[@shivanisingh7964]

Sometimes

[@f.rjustforeducationfree507]

Thank u

[@austindeaton6978]

“AHAAA! Interesting.” 😂

[@nitizvashist3165]

Ammm...🤔that was too easy or u made it that easier ? Btw thanks 🙏 good job 👍

[@dheereshsharma697]

dear sir, what about the measurements of neg , positive and hyperergic reactions.

[@kranthikour7690]

10mm is considered as positive and less than 6mm negative. 6mm to 9mm considered doubtful

[@zhaikyeve1403]

What if its flat but theres hardened part under it? Is it positive or negative?

[@143fifie]

What happen if they inject it is not visible bubble?

[@morganhoward5010]

What happens if the health care provider injects the TB proteins into the subcutaneous fat and not the dermis?

[@blank3115]

Hi- no bubble or wheal will appear , obviously. It’s dead Tb protein so it’s not dangerous. It’s invalid and should be repeated.

[@pruthvisai8254]

If we had BCG vaccine then we get induration, but that doesn't means we had or not tb infection then we have to go for Xray and confirm it

[@AhmedAhmed-ko1ky]

what is the device you use to writing ???

[@morrislegendary5731]

Question: Suppose you had a PPD test done in the past. If you were to now go get a PPD test done again, would it now be positive since tuberculin was already introduced to the body when you had the first PPD test done?

[@mpachhangte9319]

No i would not as the primary lesion is not formed and hence is too insignificant on its own; meaning the immune system will easily take care of it before it means anything much. However in reactive individuals it may elevate the intensity of the response. However the re-test is not done at the same site.

[@ohshitdownbeach]

I did mantoux test last two years ago and still now it leaves a marked on my left forearm area

[@nefilaswanson3187]

what does it mean if the patient has 72h of a big red spot of 2cm diameter. and there is suspection of a rare Mycobacterial infection with Avis or Bovis. ? thanks

[@KaajiSaab]

Question: I had tb in the past about 7 years ago and I took 6 months of complete medication for it, now if I undergo PPD test, does it shows positive or negative?

[@alip1163]

What is the medical staff accidentally poking / burst 2 layer? Still the test valid? 😅

[@MohitDudhat]

Wow

[@toqaqutaiba8944]

😍😍😍

[@amiyaroy96]

please read KHANACADEMY: hello thank u so much for the useful videos. i do A-level and i have an exam i was wondering if you could do a video on on TISSUE FLUID or STARCH ,and GLYCOGEN if u havent please thank you!!! THUMPS UP GUYS OS HE CAN SEE =)

[@satabdeepanda6810]

Thank uhh so much sir

[@binachaulagain9871]

its easy to understand

[@gracewilliams8015]

❤

[@bheatricegreene03]

Yay i administer PPDs for my job. Its fun, but not when its for kids😂

[@layrenegolde4430]

doc tanong lang po mam sir miron po ako lavoratory ng anak q PPD test san po miron

[@ohudyansary]

Thanks. A loooooooooot

[@mdtahsin1929]

Man!! I think It's a positive result. What does that actually mean?! Am I ill?

[@whodis799]

Can someone explain it a little deeper in regards to "I recognize this/i dont recognize this"? I know how a normal infection becomes latent, but why does the t-cells not activate otherwise? Shouldn't it react the same as if there was a whole bacteria or is it because we're only putting in tuberculin?

[@avantikumari7487]

If they doesn’t recognise them this time they will form memory, but primary immune reaction will not be severe

[@whodis799]

@@avantikumari7487 Bro I really appreciate the answer, but I passed this class a year ago lmao

[@herbalmuzik6264]

They put the actual tuberculosis protein into the body? Doesn’t it affect your immune system if u keep having to take it every 6months? A lot of hospital position requires that

[@68sagandeepkaur13]

I don't think so....bcz it's just the protein and not living bacilli....so it just can't replicate and infect ur body as a living bacilli do...... Moreover it gets destroyed by macrophages after some time.......this protein however when associated with living bacilli definitely acts as virulence factor that causes tb..

[@deepaksingh-ut7lh]

👌👌👌👌👌

[@Bug_93]

That part when Police said ,"Aahan" i saw these thieves before 🤗

[@haseebrehman1212]

sir please tell me why should we read test in 48 to 72 hours?

[@kathrynmercier4874]

Because it takes time for the immune system to react. If you do not have TB, your immune system will just destroy the proteins that were injected and for the bubble to flatten (which takes time). At least, that’s my understanding from the video.

[@Drcrazy0]

I will have it today 🙄

[@abdullahaslam6356]

Was it positive

[@sniperhawk6969]

I'm watching this stuff cuz I have to do it tomorrow and I'm totally freaking out, it looks creepy and I hate needles :/

[@sniperhawk6969]

@boltsoup ahAhA too late

[@abdullahaslam6356]

How are you now

[@sniperhawk6969]

@@abdullahaslam6356 i almost passed out that day

[@haripanditparanjpe30]

If a person was vaccinated using BCG vaccine then what will happen to Mantoux test ?

[@militantpotato8671]

Haripandit Paranjpe it would be positive as per Park's PSM. or it could give a 2 step positive if the vaccine was give a long time back.

[@philipbernardo450]

Hi got a positive ppd and negative quantiferon and negative cxray result do you think i'm positive or not?

[@jedskillz]

You had a positive PPd, they usually prescribe Xray to for confirmation. If it's negative then you are negative.

[@zhaikyeve1403]

@@jedskillz what if there is history of lung scar in the xray?

[@tarhtapung3283]

Ok, not redness 🆗😂

[@cyte5148]

This dude has better handwriting than me and he's using a mouse.....wtf....

[@protonparsec2235]

Thank you.

[@RS-dw2ql]

thank you