How do i get my daughter tested for a kidney problem?

Depends on problem: Best doctors for that would be a pediatric nephrologist, but any competent internist /pediatritcian can do a good screening by checking the urine, doing a blood test for kidney problems ( serum creatinine) and a complete physical including BP measurements ultimately depends on the kidney problem you are searching for.

Kidney evaluation: Does she have frequent urinary infections? If so, the urine should be cultured and she should be treated with the proper antibiotic. If she has had more than 2-3 serious infection she should undergo an ultrasound of the kidneys and bladder. Some doctors include avoiding cystogram although most pediatric urologists no longer find it necessary.