Contact Us. Please do not include any clinical or personal information on this form. Please contact our office: 770-227-2222. Dr. Ranvir Singh, Dr. Stephen Rashbaum, Dr. Long Nguyen, Dr. Nitin Parikh, Dr. Ruth Montalvo, Dr. Jae Kim, Tammi D’Elena, PA-C, and Vanessa Bridgeman, MSN, FNP-BC. For clinical questions, please contact our office: 770 ....