What Causes Pus Cells In Urine And Swelling In Hands?

Hello Doctor,

My question is for my Mom she is 65 year old. from last 2-3 months she is complaining of dizziness. and she was fall down due to this 3-4 times. Her all reports was normal execpt the pus cells in urine and low sodium. from last 2months she is talking the antiboitics for pus cells but they are not going. she was hospitalized 3 times because of low sodium. As per doctor the sodium is coming out from urine because of pus cells. Now doctor again giving her a antibiotic injections 3 times a Day to treat the pus cells. After a ten days course her pus cell in report is 2-3.

Now pls advise if the sodium is low due to this pus cells? and 2-3 is normal?? because as per doctor it should be nil. but her both hands are full with swelling. we are very confused pls help and advise.