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What Does A Reading Of 20mm In Ppd Test Mean?
Dear Doctor,
My age is 42, 5"10 and 75 kg.
My question is when I was a child i was given a vacin when i entered in Grade 1 and now last month I stop smoking, and transfer to another work 4 times going outside and coming back in the office. I notice to my self I have cough and flu for 10 days but it seesm stoping now. My company test me PPD but it shows 20mm on first reading of result in skin, after 48 hours then after 72 hours it become 18mm. Our infections control manager still not satisfy with the result and send me today to Internist and they request for X-RAY.. and the result of X-Ray is fine normal. DOctor I am worried if I have TB.. and if I am positive I dont know if my company will deported me back to Philippines. Please help me and advice what I will do. Kind regards.
My age is 42, 5"10 and 75 kg.
My question is when I was a child i was given a vacin when i entered in Grade 1 and now last month I stop smoking, and transfer to another work 4 times going outside and coming back in the office. I notice to my self I have cough and flu for 10 days but it seesm stoping now. My company test me PPD but it shows 20mm on first reading of result in skin, after 48 hours then after 72 hours it become 18mm. Our infections control manager still not satisfy with the result and send me today to Internist and they request for X-RAY.. and the result of X-Ray is fine normal. DOctor I am worried if I have TB.. and if I am positive I dont know if my company will deported me back to Philippines. Please help me and advice what I will do. Kind regards.
Wed, 13 Aug 2014
PPD is skin test measuring hypersensitivity to the tubercular protein. It is not a diagnostic test which confirms the TB. It can give false positive reult in below mentioned conditions.
1. Childhood BCG vaccination
2. Past history of TB.
3. Contact with environmental mycobacteria.
In all above conditions IgG antibodies are made in the body. So when ever we challenge it with PPD (antigen) it causes antigen antibody reaction and gives positive result.
1. Childhood BCG vaccination
2. Past history of TB.
3. Contact with environmental mycobacteria.
In all above conditions IgG antibodies are made in the body. So when ever we challenge it with PPD (antigen) it causes antigen antibody reaction and gives positive result.
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