Genomic characterization of Staphylococcus aureus isolates causing osteoarticular infections in otherwise healthy children.

BACKGROUND: Pediatric osteoarticular infections are commonly caused by Staphylococcus aureus. The contribution of S. aureus genomic variability to pathogenesis of these infections is poorly described. METHODS: We prospectively enrolled 47 children over 3 1/2 years from whom S. aureus was isolated on culture-12 uninfected with skin colonization, 16 with skin abscesses, 19 with osteoarticular infections (four with septic arthritis, three with acute osteomyelitis, six with acute osteomyelitis and septic arthritis and six with chronic osteomyelitis). Isolates underwent whole genome sequencing, with assessment for 254 virulence genes and any mutations as well as creation of a phylogenetic tree. Finally, isolates were compared for their ability to form static biofilms and compared to the genetic analysis. RESULTS: No sequence types predominated amongst osteoarticular infections. Only genes involved in evasion of host immune defenses were more frequently carried by isolates from osteoarticular infections than from skin colonization (p = .02). Virulence gene mutations were only noted in 14 genes (three regulating biofilm formation) when comparing isolates from subjects with osteoarticular infections and those with skin colonization. Biofilm results demonstrated large heterogeneity in the isolates' capacity to form static biofilms, with healthy control isolates producing more robust biofilm formation. CONCLUSIONS: S. aureus causing osteoarticular infections are genetically heterogeneous, and more frequently harbor genes involved in immune evasion than less invasive isolates. However, virulence gene carriage overall is similar with infrequent mutations, suggesting that pathogenesis of S. aureus osteoarticular infections may be primarily regulated at transcriptional and/or translational levels.

Advanced Inpatient Management of Opioid Use Disorder in a Patient Requiring Serial Surgeries.

Opioid use disorder has affected many lives across the US. Medications for opioid use disorder (MOUD), including buprenorphine, have been shown to decrease mortality in this patient population. Here we present a case of a 32-year-old woman on buprenorphine/naloxone undergoing multiple surgical operations, whose course included buprenorphine discontinuation, methadone initiation, and buprenorphine re-induction using a novel "microdosing" approach. This report includes a presentation of the case and a discussion of the clinical decision making and relevant literature to give hospitalbased providers a perspective on management of peri-operative patients on MOUD.

Pancreatic neuroendocrine tumor in a patient with a TSC1 variant: case report and review of the literature.

The majority of pancreatic neuroendocrine tumors (PNETs) are sporadic while 10-15% are attributable to one of several familial cancer syndromes. Hereditary forms are more commonly associated with Multiple Endocrine Neoplasia Type I and von Hippel Lindau Syndrome. However, patients with Tuberous sclerosis complex also have an increased incidence of PNETs. More often this has been reported in patients with TSC2 variants. In this case report, we summarize the literature regarding PNETs associated with Tuberous sclerosis complex, as well as present a case of a patient with a TSC1 variant and a PNET. This case highlights the association of TSC1 gene variants with these tumors and emphasizes the importance of considering such diagnoses in this patient population.

High levels of tumor-associated neutrophils are associated with improved overall survival in patients with stage II colorectal cancer.

Conflicting reports regarding whether high tumor-associated neutrophils (TAN) are associated with outcomes in colorectal cancer (CRC) exist. Previous investigators have counted TAN using non-neutrophil-specific immunohistochemistry (IHC) stains. We examined whether TAN levels as determined by multi-field manual counting would predict prognosis. IRB approval was obtained and two pathologists, blinded to stage/outcome, counted TAN in 20 high power fields (HPF) per specimen. TAN score was defined as the mean of these counts. High TAN was defined as at or greater than the median score for that stage. Demographics, tumor characteristics, and overall survival (OS) were obtained from the records and examined for association with TAN score. IHC for arginase expression was performed in a subset of samples. 221 patients were included. Stage II patients with high TAN scores had an OS of 232 months as compared to those with low TAN (OS = 85 months, p = 0.03). The survival benefit persisted in multivariable analysis (HR 0.48, CI 0.25-0.91, p = 0.026) controlling for age and sex. Women had increased survival as compared to men, and there were no significant prognostic associations with TAN count in stage III/IV patients, although there were only 12 stage IV patients. Arginase staining did not provide additional information. Stage II colorectal cancer patients with high TAN live nearly 3 times longer than those with low TAN. Women with stage II disease and high TAN counts appear to be driving the survival benefit seen in the stage II patients and have increased overall survival in all stages.