If you have not heard of Yellow Nail Syndrome (YNS), well it is all right because this disorder is very rare. Yellow Nail syndrome is a combination of lymphedema or swelling of the lower extremities, bronchiectasis, recurrent pneumonia, and nails turning yellow. In most of the patients it is manifested as the disease of the lower lobes of the lungs. It might be caused by infection of the lungs or some kind of obstruction. Bronchiectasis is a disorder in which one or more of the bronchi get enlarged irreversibly. It occurs because of the damage to the muscular and elastic supporting tissues.

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