Thanks for your question on Healthcare Magic.
I can understand your concern.
Rheumatoid arthritis (RA) is auto immune disease which affects major organs of body like lungs, heart, kidneys, Brain etc.
Lung involvement in RA is very common.
Your pleural thickening is mostly due to RA affecting the lungs.
Honestly speaking, this is not a good sign as far as prognosis is concerned.
You should definitely get done
CT scan of thorax to find out other lesions in lung because chest
x ray is not always sufficient.
So
consult pulmonologist and discuss all these.
You will mostly need periodic (six monthly) CT scans to see for any new lesion development.
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.