Factors associated with sepsis development in 606 Spanish adult patients with cellulitis

Background

Cellulitis, a frequent cause of admission of adult patients to medical wards, occasionally evolves to sepsis. In this study we analyze the factors related to sepsis development.

Methods

Prospective and observational study of 606 adult patients with cellulitis admitted to several Spanish hospitals. Comorbidities, microbiological, clinical, lab, diagnostic, and treatment data were analyzed. Sepsis was diagnosed according to the criteria of the 2016 International Sepsis Definitions Conference. Multiple logistic regression modelling was performed to determine the variables independently associated with sepsis development.

Results

Mean age was 63.4 years and 51.8% were men. Overall 65 (10.7%) patients developed sepsis, 7 (10.8%) of whom died, but only 4 (6.2%) due to cellulitis. Drawing of blood (P < 0.0001) or any (P < 0.0001) culture, and identification of the agent (P = 0.005) were more likely among patients with sepsis. These patients had also a longer duration of symptoms (P = 0.04), higher temperature (P = 0.03), more extensive cellulitis (P = 0.02), higher leukocyte (P < 0.0001) and neutrophil (P < 0.0001) counts, serum creatinine (P = 0.001), and CRP (P = 0.008) than patients without sepsis. Regarding therapy, patients with sepsis were more likely to undergo changes in the initial antimicrobial regimen (P < 0.0001), received more antimicrobials (P < 0.0001), received longer intravenous treatment (P = 0.03), and underwent surgery more commonly (P = 0.01) than patients without sepsis. Leukocyte counts (P = 0.002), serum creatinine (P = 0.003), drawing of blood cultures (P = 0.004), change of the initial antimicrobial regimen (P = 0.007) and length of cellulitis (P = 0.009) were independently associated with sepsis development in the multivariate analysis.

Conclusions

Increased blood leukocytes and serum creatinine, blood culture drawn, modification of the initial antimicrobial regimen, and maximum length of cellulitis were associated with sepsis in these patients.

Segregation induced by inelasticity in a vibrofluidized granular mixture

We investigate the segregation of a dense binary mixture of granular particles that only differ in their restitution coefficient. The mixture is vertically vibrated in the presence of gravity. We find a partial segregation of the species, where most dissipative particles submerge in the less dissipative ones. The segregation occurs even if one type of the particles is elastic. In order to have a complete description of the system, we study the structure of the fluid at microscopic scale (few particle diameters). The density and temperature pair distribution functions show strong enhancements with respect to the equilibrium ones at the same density. In particular, there is an increase in the probability that the more inelastic particles group together in pairs (microsegregation). Microscopically the segregation is buoyancy driven, by the appearance of a dense and cold region around the more inelastic particles.