Grade 2B vesicoureteral reflux

  my 13 month old daughter was just diagnosed with grade 2 b reflux in her left kidney.  She has had one Dx. UTI.
  - What is the difference between grade 2 and grade 2B?
  - Does the condition ever progress to a higher grade?
  - At what age does this resolve or can it continue into adult-hood?
  -I also have twin daughters age 6.  Should they be evaluated as well?
  -Is there any long-term problem with taking prophylatic antibiotics?
  Thank you

[hfhs M.D.-AK]

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Dear Kathy,
To begin with, I do not know the terminology you are referring to.  I ask some of my collegues and they are not familiar with this 2B classification.  I