Sheesh! I totally understand your frustration. I was once a medical secretary and I would never speak to any of the patients in that way. I would definately ask to speak to the office manager and explain what exactly took place between you and the receptionist.
Also I would mention it to your doctor the next time you come in contact with him/her. They will certainly nip that type of stuff in the bud when they hear it come from their patients.
This girl definately needs a change of attitude if she wants to continue to work in healthcare.
Sorry to hear that someone had to start your day off like this. Hope everything works out for you with your results and your Remicade treatment.