Simon Laboratory
Research Topics
Improving the evidence base for inpatient care provided to children with medical complexity, including but not limited to:
- Describing the microbial environment of cerebrospinal fluid (CSF) shunt infections
- Determining risk factors and optimizing treatment for CSF shunt infections and re-infections
- Improving surgical decision-making to prevent CSF shunt infection
- Identification and characterization of healthcare utilization by children with medical complexity
Research Overview
Our study team is driven by a talented group of research staff and collaborating sites who address translational, clinical and health services research projects. We are committed to improving the quality of evidence in the inpatient health care provided to children with medical complexity.
The laboratory of Tamara D. Simon, MD, MSPH, focuses on cerebrospinal fluid (CSF) shunt infections and re-infections in children with hydrocephalus.
In 2009, Dr. Simon obtained a K23 career development award from the National Institute of Neurological Disorders and Stroke. The grant allowed her to conduct multicenter studies to determine risk factors for CSF shunt infections through the Hydrocephalus Clinical Research Network, expanding upon similar work conducted using single center data and multicenter administrative databases.
While finding relatively few patient factors are associated with risk for first CSF shunt infection, we have learned that implementing a standardized surgical protocol reduced CSF shunt infection rates. The team is now pursuing the effectiveness of intrathecal antibiotics and antibiotic impregnated shunt catheters in preventing post-surgical CSF shunt infection. A grant to investigate this question using the PHIS+ database (PHIS+ Shunt Infection Prevention) is being supported through a R01 grant from the National Institute of Neurological Disorders and Stroke.
Our team’s subsequent translational line of inquiry has focused on the microbial environment of CSF shunt infections. With new collaborators, we have described wide bacterial and fungal diversity in the CSF of children with CSF shunt infections, and are actively investigating the presence of biofilms on shunt apparatus. A grant to characterize the CSF microbiota across the time course of shunted hydrocephalus (Cerebrospinal FLuId MicroBiota in Shunts Study or CLIMB) is being supported through an R01 grant from the National Institutes of Neurological Disorders and Stroke.
Additionally, the team’s health service research focus is on improving the quality of care provided to children with medical complexity in the inpatient setting. It is critical to accurately identify this vulnerable population of children to study and better understand where evidence gaps exist in their care and to inform the development of interventions to improve their care.
Dr. Simon was the scientific lead of the AHRQ-funded Working Group on Identification of Medically Complex Children in Administrative data, and a driving force for the development of the Center’s strategy to identify children with medical complexity in Medicaid administrative data. The resulting Pediatric Medical Complexity Algorithm (PMCA) identifies children with medical complexity with high sensitivity and specificity using hospital discharge or health plan administrative data. PMCA is now in use by multiple institutions both nationally and internationally. A grant investigating utilization by children with medical complexity in rural and urban settings was recently awarded to Dr. JoAnna Leyenaar at Dartmouth.
Meet Our Team
- Lab Members
- Lab Trainees
Tamara D. Simon, MD, MSPH
Principal Investigator
Katie Whitlock, MS
Biostatistician
Katie Whitlock (New Harmony Statistical Consulting LLC) supports Simon Lab research initiatives as its Biostatistician, Data Manager and general analytic Jack-of-all-Trades. Driven by a passion for improving patient care and medical and psychosocial outcomes through research, Whitlock has worked in academic- and hospital-based biomedical research for over a decade. Her expertise covers frequentist modeling techniques, including generalized linear mixed models, parametric and non-parametric survival techniques, and quality improvement techniques.
Joaquin Vega, BS
Research Assistant
Joaquin Vega completed his undergraduate work at California Baptist University in Riverside, California. He works collaboratively with the research teams on the PHIS+ Shunt Infection Prevention and CLIMB clinical studies of children with hydrocephalus. Joaquin is interested in improving the quality of care for children with medical complexities and working with communities where healthcare resources are not readily available. He enjoys working with the diverse communities CHLA serves and hopes to assist these families by participating in the research projects in the Simon Lab.
Taydin Macon, BS, BA
Research Coordinator I
Taydin completed their undergraduate degrees at Loyola Marymount University and supports the Simon Lab as a research coordinator. They joined the team in September of 2022 and now works on the CLIMB study for children with hydrocephalus. As a coordinator, Taydin consents patients, collects data, and assists Dr. Tamara Simon with other study and research related tasks. Taydin enjoys the research done at CHLA and hopes to pursue a graduate degree in the future.
Paul Hodor, PhD
Principal Systems Engineer, Enterprise Analytics, Seattle Children’s Hospital
Dr. Hodor is responsible for the bioinformatics analysis of data from the microbiota project, as well as for progress reporting for team projects. He has a longstanding interest in deriving knowledge from data in the life sciences. His current interests are in developing computational tools based on big data technologies and the reconstruction of microbial genomes from clinical samples. Past focus areas include building scalable solutions for the storage of human genomic data and machine learning models and biomarker discovery for pharmaceutical research.
Shailly Pandey, BA
Shailly Pandey is a current fourth year medical student at the University of Washington School of Medicine. She has been working with the Simon lab for the last four years as a study lead for Aim 1 of the CLIMB study. She has worked with other members of the lab to organize, analyze, and evaluate data that aims to characterize the microbiota present in the cerebrospinal fluid of children with hydrocephalus at the time of first surgical intervention. Ms. Pandey is an aspiring internal medicine resident.
Evan Heller, BS
Evan Heller completed his undergraduate degree at the University of Utah, where he collaboratively supports the Simon lab with the PHIS+ Shunt Infection Prevention study. He assists in the collection of essential data elements, cleaning and verifying the integrity of collected data, and managing communications with the local institutional review board. He is currently the study lead for Aim 2.2 of the PHIS+ Shunt Infection Prevention study. His research interests include improving care for children with common and uncommon infectious diseases, as well as accelerating the translation of research to bedside practice.
Stacey Podkovik, DO
Stacey Podkovik is a 6th year neurosurgery resident at Riverside University Health System who is planning on pursuing a fellowship in pediatric neurosurgery. He completed his undergraduate education at the University of Illinois at Urbana-Champaign, followed by medical school at Lake Erie College of Osteopathic Medicine. He became part of the Simon Lab in 2021 after completing his pediatric neurosurgery rotation at Children’s Hospital Los Angeles. He currently is a study lead for Aims 1.1 and 1.2 of the PHIS+ Shunt Infection Prevention study, where he offers a neurosurgical perspective on shunt practices and pathologies. His professional interests include pediatric brain tumors, craniofacial abnormalities, and of course, hydrocephalus (any pediatric neurosurgeon’s favorite).
Sabrina Sedano, BS
Sabrina Sedano completed her undergraduate studies at the University of California, Riverside. She joined the Simon Lab in 2020 and worked collaboratively with the research teams on the PHIS+ Shunt Infection Prevention and CLIMB clinical studies of children with hydrocephalus. During her time in the Simon Lab, she worked closely with families participating in the research projects, oversaw data workflow and archiving, as well as assisted in grant preparation and submissions. Sabrina has recently matriculated to the UCSF School of Medicine where she will be part of the PRIME-US cohort. She is interested in helping improve the quality of care for children with medical complexities and promoting research among marginalized communities.
Participating Sites
- PHIS+ Shunt Infection Prevention
- CLIMB
- Alumni
Boston Children’s Hospital
Site Investigator: Benjamin Warf, MD
Children’s Hospital Association
Site Investigator: Matt Hall, PhD
Children’s Hospital of Philadelphia
Site Investigator: Susan Coffin, MD
Children’s Hospital of Pittsburgh
Site Investigator: Ian Pollack, MD
Cincinnati Children’s Hospital Medical Center
Site Investigator: Francesco Mangano, MD
Primary Children’s Hospital
Site Investigator: Emily Thorell, MD
Co-Investigator: Ram Gouripeddi, PhD
Seattle Children’s Hospital
Site Investigator: Jason Hauptman, MD
Co-Investigators: Boots Kronman, MD, and Chuan Zhou, PhD
University of Washington
Co-Investigator: Paul Fishman, PhD
Washington University in St. Louis
Site Investigator: David Limbrick, MD, PhD
British Columbia Children’s Hospital
Site Investigator: Patrick McDonald, MD
Seattle Children’s Hospital
Site Investigator: Jason Hauptman, MD
University of Washington
Site Investigator: Luke Hoffman, MD, PhD
Wayne State University
Site Investigator: Carolyn Harris, PhD
PHIS+ Shunt Infection Prevention
Stephen Chun – Seattle Children’s Hospital
Leslie Davis – Children’s Hospital of Philadelphia
Emily Day – Boston Children’s Hospital
Kimberly Diamond – Children’s Hospital of Pittsburgh
Richard Drake – Primary Children’s Hospital
Evan Heller – Primary Children’s Hospital
Emily Insalaco – Children's Hospital of Pittsburgh
Madeline Karsten – Boston Children’s Hospital
Kellie Liston - Children’s Hospital of Philadelphia
Julie McGalliard – Seattle Children’s Hospital
Sarah Mierke – Cincinnati Children’s Hospital Medical Center
Tina Mounlavongsy – Boston Children's Hospital
Alex Platt-Koch – Primary Children’s Hospital
Roshni Prabhu – Seattle Children’s Hospital
Alex Rangel-Humphrey – Seattle Children’s Hospital
Coleman Riordan – Boston Children’s Hospital
Ashton Roach – Cincinnati Children’s Hospital Medical Center
Michael Russo – Children’s Hospital of Philadelphia
Linda Shih – Seattle Children’s Hospital
Fanmuyi Yang – Cincinnati Children’s Hospital Medical Center
CLIMB
Haley Botteron – Washington University in St. Louis
Alex Cheong – British Columbia Children’s Hospital
Julie McGalliard – Seattle Children’s Hospital
Diego Morales – Washington University in St. Louis
Amanda Morgan – Washington University in St. Louis
Chris Pope, PhD – University of Washington
Roshni Prabhu – Seattle Children’s Hospital
Alex Rangel-Humphrey – Seattle Children’s Hospital
Linda Shih – Seattle Children’s Hospital
Publications
Publications are up to date at https://profiles.scctsi.org/tamara.simon
- CLIMB
- PHIS+ Shunt Infection Prevention
Simon TD, Schaffzin JK, Stevenson CB, Willebrand K, Parsek M, Hoffman LR. Cerebrospinal fluid shunt infection: Emerging paradigms in pathogenesis that affect prevention and treatment. J Pediatr. 2019 Mar;206:13-19. doi: 10.1016/j.jpeds.2018.11.026. Epub 2018 Dec 6. PMID: 30528757; PMCID: PMC6389391.
Hodor P, Pope CE, Whitlock KB, Hoffman LR, Limbrick DL, McDonald PJ, Hauptman JS, Ojemann JG, Simon TD. Molecular characterization of microbiota in cerebrospinal fluid from patients with CSF shunt infections using whole genome amplification followed by shotgun sequencing. Front Cell Infect Microbiol. 2021 Aug 20;11:699506. doi: 10.3389/fcimb.2021.699506. PMID: 34490140; PMCID: PMC8417900.
Whitlock KB, Pope CE, Hodor P, Hoffman LR, Limbrick DL Jr, McDonald PJ, Hauptman JS, Ojemann JG, Simon TD; Cerebrospinal fLuId MicroBiota in Shunts Study (CLIMB) Group. Characterization of cerebrospinal fluid (CSF) microbiota from patients with CSF shunt infection and reinfection using high throughput sequencing of 16S ribosomal RNA genes. PLoS One. 2021 Jan 6;16(1):e0244643. doi: 10.1371/journal.pone.0244643. PMID: 33406142; PMCID: PMC7787469.
Current Funding
- The National Institutes of Neurological Disorders and Stroke
- National Institute on Minority Health and Health Disparities
- Southern California Clinical and Translational Science Institute
Completed Funding
- The National Institutes of Neurological Disorders and Stroke
- National Heart, Lung, and Blood Institute
- Patient-Centered Outcomes Research Institute
- Agency for Healthcare Research and Quality Centers for Medicare and Medicaid Services
- Center for Clinical and Translational Research at Seattle Children’s Research Institute
- Seeking Techniques in Advancing Research in Shunts
- Primary Children’s Medical Center Foundation
- Clinical Center for Translational Science Pilot Project at University of Utah
Data and Specimen Request
If you and your research team are interested in using the PHIS+ data please email your request to tsimon@chla.usc.edu. Please include the institution you are affiliated with as well as your contact information.
If you and your research team are interested in using our biospecimens repository please email your request to CSFMicrobiota@chla.usc.edu. Please include the institution you are affiliated with as well as your contact information