What Causes Pain In Finger Joints Of A Child Suffering From Fever?

My 10 year old granddaughter gets sharp electricla like pain in her finger and toe joints when she has a fever and occassionaly when no fever is involved. They last only a few seconds and then they re gone. Her sed rate is 38 but all other factors are normal. She is active and healthy with no swelling invovling the joints. She does have allergies and also has an implant for precosious puberty. We have not seen a rheumatologist but we do have an appointment later in the month. We have also already ruled out R.A. through her pediatrician, who has scheduled the appointment with the rheumatologist. I m beside myself with fear. Is there anyway this is not related to an auto immune disease?