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Our mission is to provide compassionate, quality, patient-centered care to patients with kidney disease and hypertension. We focus our care on the needs of the individual patient coupled with the best, state-of-the-art standards in our field. 

The Full Story


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Dr. Sankar Niranjan

I am currently the oldest member of the GHN team. Born and raised in Chennai, India where the 3 seasons of the year are called “hot, hotter and hottest”. I became a New Englander in 1998 and appreciated the 4 seasons as did my residency at UCONN where I completed my training as a board-certified nephrologist.

Having had multiple family members with end-stage kidney disease has given me a unique insider’s perspective to what it means to be on dialysis or receive a transplant. Their stories, and the fighting spirit of my patients inspire me every single day to the do the work that I am doing.

Prevention of kidney disease has been my passion – I have worked with the National Kidney Foundation in organizing screening camps both here locally and across the world to help identify kidney disease at early stages so that it can be treated effectively. I also actively teach the next generation of physicians the nuances and practical aspects of nephrology.


  • I enjoy traveling with my family immensely, having seen the world from Iceland to New Zealand in the last decade

  • I have been an avid biker since my teen years

  • I enjoy yoga, meditation, and am fascinated by Advaita philosophy (Oneness) that has segued into my interest in spirituality and interfaith dialogue.

  • The language I speak at home is one of the oldest spoken languages in the world – Tamil.

Dr. Christine Vigneault 

I am a native New Englander and grew up by the shoreline in Branford, CT.  I went to the University of Connecticut for my undergraduate studies. I completed my medical school training at Eastern Virginia Medical School in Norfolk, VA before returning to Connecticut to complete my residency training in internal medicine at UConn. I also acted as Chief Medical Resident during my training at the University of Connecticut.  I completed my nephrology training at Yale before joining Greater Hartford Nephrology in 2011.

My nephrology interests include glomerulonephritis, electrolyte disturbances, chronic kidney disease care and prevention. I want to ensure my patients understand their kidney related problems. I believe that one must understand their health conditions in order to gain control over their health. In addition, I have particular interest in care of patients on peritoneal dialysis and transplant.

I act as medical director of the in center and home dialysis programs at Davita Hartford.  My role in the practice is both clinical and in helping with the administrative tasks of the practice.


  • I enjoy spending my free time with my husband and our dog, Ozzy.

  • I love anything outdoors including gardening, swimming, hiking and camping. 

  • I also enjoy working with my hands. I am an avid knitter and always have several works in progress. Most recently I began getting my hands dirty as a novice potter.


Dr. Ari Geller

I grew up in a small town in Westchester New York, and received my undergraduate education at Washington University in St Louis. I received my medical degree at New York College of Osteopathic Medicine (NYCOM) in Westbury, NY.

I am a board certified clinical nephrologist and have been in practice since 2008.  My residency, chief residency and nephrology fellowship were completed at Lenox Hill Hospital in New York City.  After fellowship, I moved to the Hartford area and have been a part of this amazing community ever since. I find the subject of nephrology fascinating, as a whole, and manage all aspects of nephrology including acute kidney injury, hypertension, electrolyte disturbances and chronic kidney disease. I have a special interest in hyponatremia (low sodium) and also ADPKD (polycystic kidney disease).  Always engaged in research, I have been the primary investigator in clinical trials spanning hyponatremia (low sodium), anemia, hypertension (high blood pressure) and chronic kidney disease.

My intention, as a doctor, is to help patients skillfully manage their kidney disease and high blood pressure. Being diagnosed with kidney disease can be a scary experience, and I feel that I have the experience, patience and compassion to guide them through this difficult diagnosis. My goal is to help patients make the correct decisions in order to improve their overall health.  I truly value my long term relationships with my patients and their families.   


  • In my free time I enjoy biking, running and skiing.

  • I love spending time with my family and my dog. 

  • I am also a consummate foodie and enjoy dining out and cooking. 

Dr. Meghana Gaiki

I did my medical schooling from NTR university, at the prestigious state School of Osmania Medical College, Hyderabad, India. After a couple of research jobs at different hospitals in NJ, I was accepted into the Internal Medicine residency program at Lenox Hill Hospital, NYC. I stayed on to complete fellowship in Nephrology during which time it became affiliated with Northwell Health. After a brief stint of jobs in Santa Rosa, California, I moved back to the East Coast to join Greater Hartford Nephrology and I have been here since 2014! 


The most fulfilling part of my job is that I can be of assistance to people who suffer from kidney disease and help them through all stages of the disease. Whether it’s a new diagnosis of kidney injury that can be treated and hence prevent progression to end stage kidney disease or helping people navigate through the different dialysis options or kidney transplant or blood pressure issues, I find my job deeply satisfying. I help run the nephrology clinic at Saint Francis Hospital which aims at providing care to the underserved in the Hartford area.



  • I am married and have 3 boys- a teenager and a set of twins, so there is never a dull day!

  • We adopted a Great Pyrenees Hound mix named Susie at the beginning of the pandemic and she completes our family! 

  • I love hiking, biking, nature walks with Susie, organizing, home staging and decor!

  • I love to curl up with a good mystery novel and attempt to solve the mystery myself.  Perhaps that’s why nephrology appeals to me because it’s a lot of investigative work!


Dr. Sharad Sathyan

A South India native, I immigrated to Connecticut to continue my medical training in 2006. After completing my residency and chief residency at the University of Connecticut, I completed my nephrology training at The New York Presbyterian Hospital in 2012. I then spent an additional year as a fellow in kidney transplantation at The Mount Sinai Hospital in New York.  Aside from kidney transplantation, I also have a keen interest in onco-nephrology which stems from time spent at Memorial Sloan Kettering Cancer Center during my fellowship.  Before returning to Connecticut and joining Greater Hartford Nephrology in 2017, I practiced in rural Missouri and New York’s beautiful Hudson Valley. I enjoy being part of this energetic and compassionate practice, driven towards providing exceptional care and improving the health of our patients.


  • I'm an avid sports fan. I especially enjoy following the English Premier League and the NFL. 

  • I am fluent in 4 languages.

  • I enjoy spending time with my family and have a keen interest in fitness, playing tennis, grilling, and learning about our financial system.

Thoa Nguyen, APRN

I have been an Advanced Practice Registered Nurse for a little over 10 years. I received my Master of Science in Nursing from University of Connecticut in 2011. I am board certified by American Nursing Credentialing Center with Acute Care focus. I worked in an intensive care unit for a couple years after I graduated and subsequently joined this growing practice since 2013.


I have an interest in all aspects of nephrology. My role as a nephrology nurse practitioner is to diagnose, treat, manage and educate patients with different stages of chronic kidney disease and other diseases related to kidney. I enjoy working with patients, helping them to understand their disease process and hopefully making a positive impact on their health and lives.



  • Outside of work, some hobbies I enjoy doing are hiking, kayaking, meditation, and traveling.

  • I never had meatloaf.


Sheldon Stock, APRN

I was born in Connecticut and have lived here my entire life.  My journey as a healthcare professional began as a CNA at Hartford Hospital in the emergency department while attending nursing school. I earned my BSN in nursing from Mount Saint Mary’s College, in Newburgh, NY in 2009. I received my MSN from the University of Connecticut, and became a board certified Adult Gerontology Acute Care Nurse Practitioner in 2015. I joined Greater Hartford Nephrology, LLC in 2016. 

My nephrology interests include HTN, CKD, ESKD management and transplant. My role in the practice clinically includes both inpatient and outpatient setting specifically the hospital, office, and dialysis clinics. 


  • When I am not working, I try to spend as much time as I can outdoors. I enjoy hiking with our newfoundland Rockford, running, fishing, and kayaking.

  • I’m an avid sports fan and huge animal enthusiast.

  • My fiancé and I purchased our 100-year-old dream home that we are currently renovating together with family and friends.

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