Testing for Deficiency, Allergies and Imbalance in the Body to Find Cause of Acne

I have been on accutane for 6mths which i stopped at ard sep 2009. My oiliness of my face has decreased and only my T-zone is still oily. But i still get acne around my cheeks ,jaw and behind my ears. Oil doesnt seem to be the cause of my acne. Can someone with relevant knowledge provide info as to who i can consult to test for deficiency , allergies and imbalance in the body , finding the root cause of my acne? Any help or advice would be deeply appreciated.