Mediastinal or Hilar Adenopathy

Can you please explain this in laymans terms:
FINGINGS:
There are trace bilateral pleural effusions with adjancen atelectassis. Significant mediastinal or hilar adenopathy is identified.

[National Jewish Health]

The lungs are encased in a thin membrane, called the pleura.  A similar membrane covers the entirety of the inner side of the chest wall.  These membranes are lubricated as to be able to slide past each other without friction, as the lungs contract and expand.  Normally, this coating of mucus is the only thing between the 2 membranes and there is no actual space between them.  Pleural effusions are collections of liquid consisting of clear fluid, blood, pus or lymph, and these collections are always abnormal and indicative of disease.  As the fluid expands, it can cause the lung immediately adjacent to it to collapse.  This lung in proximity to the fluid may be normal or diseased.

"Trace" means that the effusions are very small and that means that it may not be possible to withdraw fluid.  If an attempt is made to withdraw fluid from the effusions, it should be done with "CT guidance".

I wonder if the second sentence was intended to read, "No significant...”

If I am wrong and there is enlargement of the lymph nodes, located in or near the middle of your chest, this too is definitely abnormal.  It will probably be necessary to biopsy one or more of the nodes.  There are a number of ways to do this, some less "invasive" than others.  You should discuss the significance of these findings with your doctor and if he/she confirms that the findings are significant, you should request consultation with a lung specialist.

Good luck.