Margaret L. McNairy, MD, MSc
David C. and Betty Farrell Professor of Medicine, Chief – Division of General Medicine & Geriatrics, and Chief – Division of Hospital Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
- Email: mcnairy@nospam.wustl.edu
Michael Lin, MD, SFHM
Section Chief of Hospital Medicine, Associate Professor of Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Tabitha Gruskowski, NP
Nurse Practitioner Fellow
- Phone: 314-362-1700
- Fax: 314-362-9878
Tabitha Gruskowski, NP, is a Nurse Practitioner Fellow in the Division of Hospital Medicine at WashU Medicine. Tabitha is an accomplished nursing professional, with a Master of Science in Nursing with a focus on Adult Geriatric Acute Care Nurse Practitioner from Saint Joseph’s College in Maine. She holds a Bachelor of Science in Nursing from the University of New England and a Bachelor of Arts in Health Sciences from Stonehill College. Since 2021, Tabitha has worked as a Registered Nurse at Massachusetts General Hospital, where she also served as a Clinical Nursing Instructor. Her extensive experience includes roles at Newton Wellesley Hospital, clinical rotations at Lahey Medical Center, and certification in neurology and epilepsy nursing. Tabitha is a recipient of the Massachusetts General Hospital Pillars of Nursing Excellence Award and is committed to advancing patient care and safety through her research efforts.
Lucas Gu, DO
Instructor in Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Dr. Lucas Gu joined the Department of Medicine in the Division of Hospital Medicine as an Instructor in October 2025. Dr. Gu is from Madison, Wisconsin. He obtained his Bachelor of Science degree in Biochemistry from University of Wisconsin Madison in 2011. Before beginning medical school, Dr. Gu was a research specialist at Center for Cardiovascular Research at the University of Illinois at Chicago where he performed research in calcium regulation and homeostasis in heart failure cardiomyocytes. Dr. Gu obtained his medical degree from Des Moines University of Osteopathic Medicine and went on to complete his internship and residency training in internal medicine at Saint Louis University Hospital in 2019 with a focus on global health. Dr. Gu plans to continue to be involved in medical education and global health.
Geneva Guarin, MD
Instructor in Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Geneva E. Guarin, MD, MBA, is a Clinical Instructor in Medicine. She completed her Internal Medicine residency training at Albert Einstein Medical Center in Philadelphia, Pennsylvania in June 2023. Currently she serves in the BMT/Oncology committee. Her areas of interests include medical education, quality improvement projects, hematology and oncology research, and wellness in hospital medicine. She is passionate about lifelong learning and taking care of patients.
Maria Gurrieri, MD
Instructor in Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Maria Gurrieri, MD, is a Staff Physician at Barnes-Jewish Hospital and a Voluntary Clinical Instructor in Medicine. She works full time taking care of patients in the Pulmonary Progressive Care Unit, Bone Marrow Transplant service, Hospitalist service, and at PCDC. She serves in the Faculty Development Committee, where she contributed to the development of the “Roads to Success” seminar series for the hospitalist faculty.
Anna Haceaturean, PA
Physician Assistant
- Phone: 314-362-1700
- Fax: 314-362-9878
Anna Haceaturean is a physician assistant for the Division of Hospital Medicine. Anna started her educational journey by completing her Bachelor of Arts in History and Russian Studies from Washington University in 2008. She went on to pursue her Master of Arts in Teaching and graduated in 2009. In 2019, she received her Master of Medical Science in the Physician Assistant Program at Saint Louis University. Anna worked as a hospitalist for BJC Medical Group at Missouri Baptist Hospital before joining the division in February of 2023. She is committed to providing and implementing quality evidence-based care.
Lana Hamieh, MD
Assistant Professor of Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Parneet Kaur Hari, MD
Instructor in Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Parneet Kaur Hari, MD, joined the Division of Hospital Medicine at WashU Medicine as an Instructor in Medicine in July 2025. She was born in Bathinda, a small town in the state of Punjab, India, in 1996. She completed her medical education at Government Medical College in Patiala and graduated with an M.B.B.S. degree in 2021. Hari moved to the United States to pursue residency training in Internal Medicine at Henry Ford Jackson Hospital in Michigan in July 2022. Her research interests include hepatology, liver immunology, the gut-liver axis, and the gut-brain axis. She is passionate about healthcare media and patient awareness, aspiring to make medical knowledge more accessible while fostering clarity, trust, and public understanding. She enjoys teaching medical students and residents, promoting an environment that encourages continuous learning and growth in the field of medicine.
Krysta Heath, MD
Assistant Professor of Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Krysta Heath, MD, is an Assistant Professor of Medicine in the Division of Hospital Medicine. She completed internal medicine residency at Washington University in St. Louis/Barnes-Jewish Hospital. Her primary role is direct care of hospitalized patients at both Barnes-Jewish Hospital and Barnes-Jewish West County Hospital. She has a particular interest in nocturnist medicine. She serves on the patient care operations committee and has an interest in patient triage and throughput as well as admission efficiency.
Benjamin Hoemann, MD
Instructor in Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Benjamin L. Hoemann, MD, is an Instructor in Medicine in the Division of Hospital Medicine. He received his medical degree from the Columbia University Vagelos College of Physicians and Surgeons and completed his internal medicine residency at Washington University in St. Louis / Barnes-Jewish Hospital. He has a special interest in addiction medicine and implementation science. He is the inaugural Hospital Medicine Research Fellow and a member of the quality improvement and patient safety and research committees within the division. He works as an attending physician on the general medicine and teaching hospitalist services.
Thomas Hoyt, MD
Assistant Professor of Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Thomas Hoyt, MD, is an Assistant Professor of Medicine in the Division of Hospital Medicine with special interests in resident and undergraduate medical education. He currently serves on the Gateway Medicine Clerkship Clinical Competency Committee for Phase 2 Medical Students. Additionally, he is a member of various committees with a focus on improving care for patients with Opioid Use Disorder (OUD). He attends on a variety of services including the General Medicine Inpatient Teaching Service as well as Hospitalist Direct Care at both Barnes-Jewish Main and West County Hospitals.
Carmen Isringhausen, DNP, AGACNP-BC
Nurse Practitioner
- Phone: 314-362-1700
- Fax: 314-362-9878
Carmen Isringhausen, DNP, is an Adult-Gerontology Acute Care Nurse Practitioner within the Division of Hospital Medicine. She received her Bachelor of Science in Nursing from Southern Illinois University Edwardsville in 2019. Her nursing experience includes acute care medicine and ambulatory care. She went on to receive her Doctor of Nursing Practice from Maryville University in 2023 and joined the Division of Hospital Medicine in 2024. She also serves on the Division of Hospital Medicine’s EMR Committee to improve EMR workflow and streamline provider level improvements.
Alvin Jeon, MD
Instructor in Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Alvin Jeon, MD, is an Instructor in Medicine in the Division of Hospital Medicine. He received his medical degree from Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo and completed his internal medicine residency at Barnes-Jewish Hospital/Washington University in St. Louis. He has a growing interest in medical education and efficient inpatient care. He attends primarily on the general inpatient hospitalist and oncology hospitalist services at this time, and he looks forward to working with students and residents.
Eric Johnson, MD
Associate Professor of Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Eric K. Johnson, MD, is an Associate Professor of Medicine in the Division of Hospital Medicine. His work responsibilities balance inpatient care on the Hospitalist and Consult services with supervising as attending on both the Firm and Procedure services. Primary interests include medical student and resident education, particularly guiding and optimizing evidence-based patient care and honing clinical problem-solving skills. Accordingly, he is a regular discussant at the weekly CPC (Clinicopathologic Conference), which showcases astute medical diagnosis through a multidisciplinary approach, and he has received multiple Teacher of the Year awards to date. He has also contributed to three consecutive editions of The Washington Manual of Medical Therapeutics. An additional, albeit more informal passion of his has been following the COVID-19 pandemic since its inception, which has so far yielded several publications in peer-reviewed journals.
Anand Kadakia, MD
Instructor in Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Dr. Anand Kadakia joined the Division of Hospital Medicine as an Instructor in Medicine in July 2024. He completed his medical education at the Government Medical College of Baroda in India. Dr. Kadakia actively engaged in community service initiatives, particularly focusing on assisting patients with sickle cell disease. He conducted research at the University of Maryland School of Medicine, investigating the role of NAD in diabetic neuropathy. Dr. Kadakia completed his Internal Medicine residency at Jersey Shore University Medical Center in New Jersey, where he prioritized serving underserved populations and leading quality improvement projects.
Lalit Kalvala, MD
Assistant Professor of Medicine
- Phone: 314-362-1700
- Fax: 314-362-9878
Lalit Kalvala, MD, is an Assistant Professor of Medicine in the Division of Hospital Medicine. He primarily works on general medicine floors and occasionally on oncology and bone marrow transplant floors. He contributes to the recruitment of hospitalists by serving as a member of the Hospitalist Recruitment Committee. Additionally, he is dedicated to patient safety and quality improvement, participating as a member of the Patient Safety & Quality Improvement Committee.