![Leonard Haas, MD](https://east.optum.com/wp-content/uploads/2022/07/Headshot-Placeholder-172x172.jpg)
Leonard Haas, MD
2800 Marcus Ave Suite 201
Lake Success, NY 11042
- Undergraduate & Graduate
- Rutgers University- B.S. in Cell Biology/Neuroscience and Public Health
- Medical Education
- Mayo Clinic School of Medicine, Rochester, MN – Doctor of Medicine
- Internship
- New York Presbyterian-Weill Cornell Medical Center
- Residency
- New York Presbyterian-Weill Cornell Medicine
- Fellowship
- John Hopkins Hospital, Pediatric Gastroenterology, Hepatology, and Nutrition,
- Hudson Spine and Pain Medicine
- Board Certifications
- American Board of Pediatrics
- Northwell Health/Cohen’s Children’s Center
- American Academy of Pediatrics, Sigma Xi, the Scientific Research Society, North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN), American Gastroenterological Association (AGA) and Crohn’s and Colitis Foundation
- Haas, L. A., Chevalier, R., Major, B., Enders, F., Kumar, S., Tung, J. (2017, November). Biologic Agents Are Associated with Excessive Weight Gain in Children with Inflammatory Bowel Disease. Digestive Diseases and Sciences. 62(11), 3110-3116. 5.
- Kolbe, A., Haas, L. A., Bartlett D., Iyer, V., Thomas, K., Tung, J., Fidler, J., Fletcher, J. (2019, October) Comparison of Two Small Bowel Distending Agents for Enterography in Pediatric Small Bowel Imaging. Abdominal Radiology. 44(10), 3252-3262.