Lymph node expansion or swelling is a process that naturally occurs whenever we have an immune reaction. This means that swollen lymph nodes are usually a sign of infection, making them very useful for diagnosis. The swelling will go down again as you recover. However, sometimes there might be a more serious cause behind this swelling especially it is prolonged and you have no other symptoms. In this case it should be checked by a doctor.
MRC Laboratory of Molecular Cell Biology University College London Gower Street London WC1E 6BT