Swollen lymph nodes, most of the time it depends on which site the lymph nodes are enlarged. There can be various reasons. It could be a simple upper respiratory infection because of which neck lymph nodes will be enlarged or a tonsil which can also give rise to a lymph node enlargement or it can be a tuberculosis, which in this case also lymph nodes are enlarged. So its always better to visit your physician to get it diagnosed whether it is for a simple upper respiratory infection, cold, cough