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Clinic Services Brochure

How to Schedule an Appointment

Clinic Provider Biographies




Seth Udlis, Medical Doctor

Agnesian HealthCare

Udlis graduated from the University of Western Ontario, Canada. He practices family medicine at the Fond du Lac Regional West Clinic and also oversees the Grande Health and Wellness Center as the Medical Director.  Udlis has been with Agnesian Healthcare for 15 years.


Melissa Tate, Advanced Practice Nurse Prescriber

Agnesian Work & Wellness

Tate received her Bachelor of Science in Nursing from University of Wisconsin-Madison, Master’s in Business Administration from Purdue University, and Master’s of Science in Nursing from Concordia University. She is certified through the American Academy of Nurse Practitioners as a family nurse practitioner. She comes to the Grande Clinics with more than 10 years of management experience, and nursing experience in cardiac care and education. Building a rapport with both patients and customers she works with is top on Tate’s priority list.


Tanya Guntly, Certified Physician Assistant

Agnesian Work & Wellness

Tanya is a nationally certified physician assistant. She received her Bachelor degree in Biomedical Sciences and her Masters degree in Physician Assistant Studies from Marquette University. She has over 15 years experience as a physician assistant and has worked as a PA in several different specialties, including Family Medicine and Neurosurgery. As a PA she believes in working as a team to deliver high quality patient centered care. She takes pride in providing compassionate patient care. She is passionate about wellness, prevention, and patient education.


Megan Diener, Nurse Practitioner

Agnesian Work & Wellness

Megan earned a Bachelor of Science degree in Nursing from the University of Wisconsin-Oshkosh. She recently earned a Master of Science degree as an adult nurse practitioner from Marian University. Diener hopes to maintain the team approach in guiding and supporting the patients she cares for with a strong belief in teamwork between the patient and provider.

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Hillary Boeke, Certified Medical Assistant

Agnesian Work & Wellness

Boeke graduated from Globe University-Middleton with a Medical Assistant degree in 2010.  She is excited to be a part of the Agnesian Work & Wellness team to promote health and wellness to Grande Cheese Associates.  She lives on a working dairy farm with her family.  In her free time, she loves to help out on the farm and spend time with her family.

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Mary Beth Trott, Certified Medical Assistant

Agnesian Work & Wellness

Mary graduated in March 2016 from MPTC Medical Assistant program, and in May 2015 from MPTC Medical Office Program. She has 20+ years working as a CNA and decided to become a Medical Assistant. Mary resides in Horicon on the Mayville side of the Marsh. She has a beautiful view of the marsh from her back patio. Mary has been married to Jeff for 32 years and enjoys spending time with her three children. Mary is very excited about her new career at Grande Health and Wellness Center. She is looking forward of using her skills she learned and working with the people from Grande.  

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Mary Mellenthin, Advanced Practice Nurse Prescriber

Agnesian Work & Wellness

Mellenthin earned her master's degree as a family nurse practitioner from Concordia University Wisconsin. Prior to her degree, she worked as a registered nurse for more than 25 years in occupational health, preventive health and wellness. She is a recipient of the prestigious Nightingale Award for excellence in nursing practice and a member of the American Academy of Nurse Practitioners. She is board certified as a family nurse practitioner and as an occupational health nurse specialist. Mellenthin provides personalized care to adults and children including wellness visits, and also manages acute and chronic health conditions.

"Getting to know my patients and their families is the best part of being a nurse practitioner and I look forward to becoming your partner and guide in healthy living."


Stefanie Petrie, Advanced Practice Nurse Prescriber

Agnesian Work & Wellness

 Stefanie graduated from the University of Wisconsin-Madison with a Bachelor of Science degree in Nursing and earned her Master of Science Nursing degree as a Family Nurse Practitioner from University of Wisconsin-Oshkosh. She has over 5 years of experience in women's health, occupational health, and acute and chronic disease management. She looks forward to working with Grande associates to achieve their wellness goals and making healthier lifestyles for themselves.

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Jennifer Hibbler, Medical Assistant

Agnesian Work & Wellness

Jennifer graduated from Moraine Park Technical College, FDL, WI with a Medical Assistant degree in 2008. She has been working with Agnesian Healthcare for 8 years. Floating in multiple departments for 3 years and Family Medicine for 5 years. She is excited to be a part of the Grande Health & Wellness team and looks forward to building relationships with the Grande team and patients.


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Cassie Detert, Medical Support Specialist

Agnesian Work & Wellness

Cassie is the new Medical Support Specialist with Agnesian Healthcare servicing Grande Health & Wellness Clinics. She has a passion for helping people and interacting with others and hopes that her experience and expertise can be of benefit to you. Prior to obtaining her role here, she worked in Real Estate as an Administrative Assistant & Personal Assistant for 3 years. In her free time she enjoys spending time with her family, being outdoors & exploring WI with her dog. She is very excited about her new career with Grande Health & Wellness and looks forward to assisting in setting up all your appointments




Roberta "Bobbi" Last, Registered Nurse/ Case Navegator

Agnesian Work & Wellness

Last is the new RN case manager with Agnesian HealthCare serving Grande Health & Wellness Clinics. Her entire career has been in the healthcare field, beginning at the age of 15 as a nursing assistant and continuing as a graduate of Marian College, now Marian University of Fond du Lac. Last has 15 years RN experience and six years of case management experience. She also worked as a nurse in corrections for eight years. Her passion is assisting people and empowering them to be knowledgeable and in control of their health. Last resides in Rosendale with her three children. She enjoys crocheting and assisting with her children's extra-curricular activities.