An old calcified spot over the hilum of lung
is an indication of a healed problem. The cause for the spot is difficult to guess without further details. Common causes include childhood tuberculosis
infection (part of healed primary complex), fungal infections, and certain occupational diseases among others.
I presume you are a non-smoker, in otherwise good health, but for this calcium shadow. If so, no further investigation is warranted. A CT scan
of thorax will give more light to the exact nature of the spot. As it is not giving you any trouble, this test is not mandatory at present.
A lung function test (PFT) may help to confirm that your lung is functioning well. You can travel or undertake any sort of work, even under tough climatic conditions.
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