Suggest Remedy For A Lump On The Leg

Hi, My aunty has just returned from Egypt and she has a lump on her leg - it is swollen and while on holiday her leg started to turn blue! She now has a rash. She has been told by a nurse that it maybe a reaction to something that she had eaten over there - does this sound right? She has been told to return to the Doctors in 5 days if it has not gone away. Thanks