Sagar Uday Nigwekar MD MMSc

Assistant in Medicine, Massachusetts General Hospital, Assistant Professor of Medicine, Harvard Medical School

165 Cambridge StSte 302Boston, MA 02114
Phone+1 585-729-8636
Fax+1 617-724-1122

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Summary

Dr. Sagar Nigwekar is a nephrologist based in Boston, MA, specializing in areas such as general nephrology, dialysis, calciphylaxis, hyponatremia, and critical care medicine. He completed his nephrology fellowship at Mass General Brigham and his internal medicine residency and chief residency at Rochester General Hospital. He serves as an Assistant Professor of Medicine at Harvard Medical School and has been a part of Massachusetts General Hospital since 2013. Dr. Nigwekar has published extensively in journals like Kidney International and the American Journal of Kidney Diseases, and has been involved in multiple clinical trials. He received the Young Investigator Award from the National Kidney Foundation in 2014 and holds several CMS Meaningful Use certifications.

Education & Training

Mass General Brigham/Brigham and Women's Hospital/Massachusetts General HospitalFellowship, Nephrology, 2010 - 2013
Rochester Regional Health/Rochester General HospitalChief Residency, Internal Medicine, 2005 - 2006
Rochester Regional Health/Rochester General HospitalResidency, Internal Medicine, 2002 - 2005
Seth G.S. Medical CollegeClass of 1999

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Certifications & Licensure

IL State Medical License 2026 - 2029
NM State Medical License 2026 - 2029
AR State Medical License 2026 - 2026
MA State Medical License 2012 - 2026
NY State Medical License 2006 - 2011
American Board of Internal Medicine Nephrology

Awards, Honors, & Recognition

CMS Meaningful Use Stage 2 Certification EpicCare Ambulatory 2014 Certified EHR Suite, Epic Systems Corporation, 2015-2017
CMS Meaningful Use Stage 1 Certification Longitudinal Medical Record, Partners Healthcare System, 2015-2017
CMS Meaningful Use Stage 2 Certification OpTime Surgical 2014 Certified Module, Epic Systems Corporation, 2015-2017

Clinical Trials

Risk Factors for Coronary Artery Calcification and Left Ventricular Hypertrophy in Hemodialysis Patients
TERMINATED
Evaluation of Vitamin K Supplementation for Calcific Uremic Arteriolopathy
COMPLETED
NA
Helping Olfaction and Nutrition On Renal Replacement
COMPLETED
PHASE2

Publications & Presentations

PubMed

Hyponatremia treatment guidelines: a necessary course correction.
Michael L Moritz, Agustín Ciapponi, Chi-Yuan Hsu, Sagar U Nigwekar, Aneesh B Singhal
Kidney International. 2026-07-27
Drug Dosing in Post-Dilution Hemodiafiltration: Pharmacokinetic Principles and Clinical Implications.
Stefano Stuard, Dinesh Chatoth, Chance Mysayphonh, Peter J Blankestijn, Bernard Canaud
Clinical Journal of the American Society of Nephrology. 2026-07-10
Calciphylaxis complicated by NDM-1-producing Pseudomonas aeruginosa: first experience with cefepime-zidebactam alongside phage therapy in the USA.
Erlinda R Ulloa, Daniel Jaffurs, M Tuan Tran, Carol Lin, Hung Tran
The Lancet. Infectious Diseases. 2026-06-09

Journal Articles

Update on the Management of Calciphylaxis
Sagar Nigwekar, MD, QJM: An International Journal of Medicine
Serum Angiopoietin‐2 Predicts Mortality and Kidney Outcomes in Decompensated Cirrhosis
Andrew S Allegretti, Sagar U Nigwekar, Raymond T Chung, Sahir Kalim, Xavier Vela Parada, Ravi I Thadhani, Guillermo A Ortiz, Samir M Parikh, Hepatology

Authored Content

Cutaneous Calcification in Patients with Kidney Disease Is Not Always CalciphylaxisJuly 2018

Press Mentions

Sparsentan for Focal Segmental GlomerulosclerosisMay 19th, 2025
SPARTAN Trial: Sparsentan Moves up to First-Line in IgA NephropathyMay 5th, 2025
Rare Disease Leaves 43-Year-Old Man with 'Penile Stump'December 11th, 2019