Sr Clinical Research Professional University of Cincinnati College of Medicine Cincinnati, Ohio, United States
Disclosure(s):
Alexander Doye, DDS: No financial relationships to disclose
Abstract: Deep neck space infections (DNSI) are a significant cause of morbidity and mortality globally. Though several factors are routinely used to predict patient prognosis, there are few factors that are serially monitored. Certain biomarkers, if monitored during the course of an infection, may correlate with resolution or persistence of infection and therefore may be used to make timely treatment choices. Two markers are currently used to monitor patient response in addition to clinical and radiographic findings, namely complete blood count and the C-reactive protein.1,2 Though both do provide dynamic information throughout the patient’s healing, there is room for more specific biomarkers. Using flowcytometry and Enzyme-linked immune absorbent spot (ELISpot), it is possible to get more detailed cellular profiling and thus more detail of the patient’s immune response. The study objectives were to determine if DSNI outcomes can be associated with temporal immune assays, to determine if dynamic functional immune assays can predict complications in DSNI patients, and to elucidate the changes in immune capacity of a DSNI patient compared to healthy controls. In order to answer the research questions, a prospective cohort study was designed. Subjects were recruited between December 2021 and December 2023 at the University of Cincinnati Medical Center (UCMC). Eligible patients were admitted to the UCMC for a DSNI, were aged 18+, and were patients of the investigators. Exclusionary criteria were patients with a history of solid organ transplant, on immunosuppressant therapy, on chronic steroid therapy, active Charcot neuroarthropathy, and/or diagnosed with HIV/AIDS. Where possible, subjects had blood draws upon admission (preoperative), withing 48 hours of discharge (postoperative), and at their one-week follow-up (± 5 days). At each encounter, 4 mL of blood was collected and analyzed with traditional CBC, differentiated with flow cytometry, and ELIspot assays. Primary predictor variable was admission for DSNI. A cohort of 10 healthy patients was used as the control reference group. Primary outcome variables included the binary outcomes of repeat imaging, airway obstruction, upper gastrointestinal bleeding, mediastinitis, and sepsis. Continuous outcome variables included intensive care unit length of stay and number of surgeries. No covariates were included in the analyses. The immune parameters at the various timepoints were then analyzed against the study endpoints by two-sample t-test as well as calculating the area under the receiver operating characteristic curve. The final study sample included 44 subjects. Eighteen subjects provided a preoperative blood sample, 32 subjects provided a postoperative sample, 6 subjects provided a follow-up sample. Nine of the 44 subjects provided preoperative and postoperative samples, and 2 patients provided preoperative, postoperative, and follow-up samples. In the final sample, 18 subjects (41%) required repeat imaging, 5 (11.4%) developed airway obstruction, 2 (4.5%), and 2 (4.5%) required surgery in follow-up. No subjects developed sepsis, mediastinitis, or an upper GI bleed. The only outcome which demonstrated a statistically significant association to the immune parameters was airway obstruction. Immune parameters white blood cell count, monocyte, and granulocyte (P > .002), as well as the ELISpot (P > .009). In conclusion, neither the addition of flow cytometry nor ELISpot testing was able to detect a statistically significant difference beyond the CBC. A small sample size may have influenced these results and as such further investigation is warranted. The study was funded by the OMS Foundation.
References:
1. Fiorella ML, Greco P, Madami LM, Giannico OV, Pontillo V, Quaranta N. New laboratory predictive tools in deep neck space infections. Acta Otorhinolaryngol Ital. 2020;40(5):332-337.
2. Gallagher N, Collyer J, Bowe CM. Neutrophil to lymphocyte ratio as a prognostic marker of deep neck space infections secondary to odontogenic infection. Br J Oral Maxillofac Surg. 2021;59(2):228-232.
