Jonathan E. Schmitz, Ph.D., M.D.
Clinical Microbiology, Molecular Diagnostics, Opportunistic pathogens, Microbe-microbe interactions, Personalized microbiology, Urinary tract infections
As a Clinical Microbiologist and investigator of microbial pathogenesis, I am drawn to academic questions in which these two sub-disciplines of microbiology complement one another. In this context, the large majority of organisms that we isolate within the diagnostic laboratory would be considered ‘opportunistic pathogens’. Although these bacteria and fungi can elicit symptomatic infections under certain circumstances, they can also represent commensal species within the body — as part the normal human microbiome — or common environmental organisms to which we are routinely exposed. The factors that govern a microbe’s balance between harmful and benign are critical in elucidating infectious mechanisms and interpreting the significance of these organisms diagnostically. My primary research efforts and collaborations address these questions of opportunistic pathogenesis, with particular emphasis on how interactions between different organisms influence pathogenic behavior. It is important to recall that opportunistic pathogens do not encounter the human host in isolation, but against the background of numerous other organisms.
This work is part of my broader interest in the ‘personalization’ or microbial discovery, in which we can re-purpose the unique, patient-specific organisms that we isolate in the clinical laboratory to dissect questions of microbial physiology and host-interaction. Much like the human host, tremendous genotypic and phenotypic diversity exists within individual strains of these same microbial species, diversity that is not well accounted for by traditional experimental models of pathogenesis. By leveraging these derivatives of clinical care for the purpose of academic discovery, I hope to better align the goals of clinical diagnosis and basic investigation.
Concurrently, I serve as the Medical Director of the VUMC Molecular Infectious Diseases Laboratory (MIDL). We are currently amidst a paradigm shift in the field of Clinical Microbiology, in which PCR and other nucleic acid techniques are complementing (or even replacing) traditional culture-based methods for diagnosing infections. At Vanderbilt, these assays — across bacterial, viral, fungal, and parasitic pathogens — are performed within MIDL, in support of the clinical mission of the Adult Hospital, Children's Hospital, and outpatient enterprise. In conjunction, I serve as an Attending on the Clinical Microbiology Service in the PMI Division of Laboratory Medicine. In this role, I provide consultative support (clinical interpretation and technical guidance) for testing that we conduct across the modalities of infectious-disease diagnostics (culture based, microscopy, molecular, and immunodiagnostic).