Machiko Oka MD is the Director of the Department of Kidney and Transplant Center at Shonan Kamakura General Hospital. She obtained her medical degree in 2001. Her residency was at Tokai University. She has twenty years of experience in nephrology, with a special interest in acid-base balance and vascular calcification in chronic kidney disease. She is a member of the American Society of Nephrology and the European Renal Association.