Meet Our Team

Outpatient Care Team

Jennifer Mayer, MD Hematology / Oncology

Dr. Mayer specializes in pediatric hematology/oncology in the Johns Hopkins All Children’s Cancer & Blood Disorders Institute and is the lead hematologist of the Vascular Anomalies Program at the hospital. She served 21 years as medical director of Johns Hopkins All Children’s collaboration with Sarasota Memorial Hospital. She is author of more than 30 publications and two textbook chapters. She joined Johns Hopkins All Children's in 1996 and received the hospital's Best Consulting Physician Award in the 2017 Johns Hopkins Medicine Clinical Excellence Awards.
View Jennifer’s Bio

Peter Shaw, MD Hematology / Oncology

Dr. Shaw is hematologist-oncologist who serves as medical director of Tampa Services for the Johns Hopkins All Children’s Cancer & Blood Disorders Institute. He joined the medical staff in August 2016 as deputy director. Dr. Shaw treats a variety of patients with blood and cancer disorders at the Tampa clinic and is recognized nationally as a leader in the areas of adolescent and young adult (AYA) oncology. He is founding member of the Consortium of Adolescent and Young Adult Cancer Centers and helped develop internationally recognized standards for care of this population. He is expanding the AYA program at Johns Hopkins All Children’s to enhance continuity of care into adulthood through multidisciplinary collaboration with physicians at Moffitt Cancer Center. He also supports the institute’s fertility preservation program, which helps pediatric cancer and bone marrow transplant survivors enjoy optimal health and the opportunity to become parents in their adult years.
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Theresa Torres, APRN

Theresa Torres, APRN



Lauren Gray, APRN

Lauren Gray, APRN



C. Isaac Hauk, PA

C. Isaac Hauk, PA

Isaac Hauk is an advanced practice provider in the Johns Hopkins All Children’s Cancer & Blood Disorders Institute. He joined the hospital staff in 2008. Hauk specializes in outpatient and inpatient pediatric hematology/oncology and is the manager and hiring manager of advanced practice providers. Hauk earned his Master of Physician Assistant degree from the University of Florida, College of Medicine in Gainesville, Florida.


Meagan Szarkowski, RN

Meagan Szarkowski, RN



AnneMarie Allushuski, RN

AnneMarie Allushuski, RN


Inpatient Care Team

Nanette Grana, MD Hematology / Oncology

Dr. Grana specializes in pediatric hematology/oncology in the Johns Hopkins All Children’s Cancer & Blood Disorders Institute. She joined the hospital medical staff in 1992. Dr. Grana earned her medical degree from the University of Puerto Rico School of Medicine. She trained in pediatrics at University Children’s Hospital in San Juan, Puerto Rico, and completed a pediatric hematology/oncology fellowship at the University of Florida.
View Nanette’s Bio

Britni Hill, MD Hematology / Oncology

Dr. Hill specializes in caring for hospitalized children in the Johns Hopkins All Children’s Cancer & Blood Disorders Institute. She started on the hospital staff in 2014, joining the hematology/oncology team in 2017.
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Daniel Ortiz, MD Hematology / Oncology

Dr. Ortiz specializes in pediatric hematology-oncology in the Johns Hopkins All Children’s Cancer & Blood Disorders Institute. He joined the hospital staff in 2018.
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Rebecca Berger, APRN

Rebecca Berger, APRN



Patti Michalski, APRN

Patti Michalski, APRN



Jamie Jennings, APRN

Jamie Jennings, APRN



Melanie Haase, APRN

Melanie Haase, APRN



Fallon Lanham, PA

Fallon Lanham, PA



Brooke Wiggins, PA

Brooke Wiggins, PA


Supportive Care Team

Melissa Faith, PhD Psychiatry / Psychology

Dr. Faith is a clinical pediatric psychologist specializing in hematology/oncology at Johns Hopkins All Children’s Hospital. She received her master’s and doctorate degrees in clinical psychology from the University of Arkansas, completed a predoctoral internship in clinical child psychology at the University of Mississippi Medical Center and completed a postdoctoral fellowship in clinical psychology with an emphasis in pediatric hematology and oncology at the University of Oklahoma Health Sciences Center. Dr. Faith’s research interests include disseminating evidence-based interventions in large medical and community centers (e.g., motivational interviewing) as well as emotion socialization, social adjustment, and sibling adjustment during and following childhood chronic illness. 
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Megan Armstrong, RD, LD

Megan Armstrong, RD, LD Dietician



Tara Hudson, CCLS

Tara Hudson, CCLS Child Life Specialist



Amanda Memken, Pharm.D, B.C.P.S., B.C.P.P.S.

Amanda Memken, Pharm.D, B.C.P.S., B.C.P.P.S. Chemopharmacy



Jessica White, Pharm.D, B.C.P.P.S.

Jessica White, Pharm.D, B.C.P.P.S. Chemopharmacy



Caroline Taylor, Pharm.D, B.C.P.S.

Caroline Taylor, Pharm.D, B.C.P.S. Chemopharmacy



JT Fannin, Pharm.D

JT Fannin, Pharm.D Chemopharmacy