Thank you for your consult at DoctorSpring.com.
The Xray has no findings suggestive of Tuberculosis.
The x ray shows an increased bronchovascular markings, - a sign of probably asthma, also seen in smokers. At times it is normal in athletes/ people who do exercise. (However, x-ray might miss upto 10% of tuberculosis cases. )
Mantoux has to be measured on day 3, and its the induration that is measured, not redness. the induration, might not be seen with naked eyes, however it has to be felt and measured. BCG taken in childhood can cause a false positive mantoux. however, it is unlikely. more likely would be a recent contact with someone who had TB.
(I assume that you do not have any symptoms of TB like cough / fever / night sweats / loss of weight)
Hope this helps
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