Dr Kumaran was born in Bhopal and brought up in Delhi. His father was a civil servant and his mother a music teacher in a well known school in Delhi. He did most of his schooling at Modern School, Vasant Vihar. He is married to Dr Nidhi Khosla, an Obstetrician and Gynaecologist, trained at Maulana Azad Medical College (MBBS, MD, Senior Residency), the Albert Einstein College of Medicine, New York (Reproductive Endocrinology) and the Western Pennsylvania Hospital, Pittsburgh (American College of Obstetricians and Gynecologists)

He graduated from High School in 1987 and qualified for admission to several engineering colleges including the IITs as well the Delhi University Medical Colleges and JIPMER Pondicherry. He joined Maulana Azad Medical College.

He completed his internship in 1992 and qualified for admission to post graduate residency programs at Delhi University, PGIMER Chandigarh and the All India PG Entrance Examination. He joined MS (Surgery) at Maulana Azad Medical College.

He worked with Dr RCM Kaza who had an interest in endourology as well as microsurgery for infertility and Dr VK Malik who had an interest in hepatobiliary and vascular surgery. After completing his MS, he joined the Guru Tegh Bahadur Hospital, attached to the University College of Medical Sciences, Delhi, as a Senior Resident. He worked with Dr Sanjay Gupta and Dr VR Minocha who had established an excellent endourology unit with a huge experience with percutaneous procedures for renal and ureteric stones. He also acquired experience with pediatric surgery and burns.

In 1998 he was selected for the prestigious M Ch Gastrointestinal Surgery post-doctoral fellowship at the All India Institute of Medical Sciences, New Delhi. He worked with Dr TK Chattopadhyay, Dr GK Pande and Dr Peush Sahni and acquired skills in advanced gastrointestinal surgery.

During his stay  at AIIMS, the Department was trying to establish a liver transplant program. He  became interested in the field and felt the need to go abroad to acquire training in Liver Transplantation at a center doing a large volume of these very demanding procedures. He began corresponding with various liver transplant centers in the US.

After he finished his MCh he had an offer to take up a  Post-Doctoral Research Fellowship at the Marion Bessin Liver Research Center of the Albert Einstein College of Medicine in New York. He took up the offer and committed himself to two years of work in the lab working on Hepatocyte Transplantation with Dr Sanjeev Gupta, one of the pioneers in the field. These years were very productive and resulted in over a dozen papers published in some of the most prestigious medical journals. During this time he  passed his US Medical Licencing Examinations and interviewed for fellowships. His first interview was at the Mount Sinai School of Medicine, New York and his second was at the Thomas E Starzl Transplantation Institute, Pittsburgh. He was offered fellowships immediately by both centers and did not interview anywhere else. The Starzl Institute, set up by Thomas E Starzl, the first person to perform a successful liver transplant and one of the most important contributors to the field of organ transplantation, is considered to be the Mecca of Liver Transplantation. Fellows of the Institute head Liver Transplant Centers all over the world and fondly remember their association with one of the giants of medical science.

He joined the Starzl Institute in 2004 and completed three years of fellowship (the third year was an optional elective year in his particular area of interest- liver Transplantation) in 2007. His search for an institution in India where he could practice the skills acquired over 20 years of varied training led him to Sir Ganga Ram Hospital where Dr Samiran Nundy and Dr AS Soin (and formerly Dr Subhash Gupta) had established a liver transplant center comparable to the best in the world as well as an elite Gastrointestinal Surgery Unit.

In July 2010, Dr Kumaran became Director of Liver Transplantation at Sir Ganga Ram Hospital. In December 2012, after having performed 105 liver transplants at Sir Ganga Ram Hospital, Dr Kumaran decided to move to Kokilaben Dhirubhai Ambani hospital where he heads the Liver Transplant and HPB Surgery Unit, one of the centers of excellence at the hospital. This is now the leading liver transplant center in Mumbai.

 In March 2018, since his family was now in the US, he began traveling back and forth between the US and India. He helped set up a new liver transplant program at Shalby Hospital in Ahmedabad.

In May 2019, he joined the Hume- Lee Transplant Center in Rochmond, Virginia and re-started the living donor liver transplant program there.