Objectives:

Among patients with cellulitis, the development of bacteraemia is associated with a high risk of adverse outcomes. We sought to identify predictors of bacteraemia at the time of presentation to the hospital emergency department in patients with cellulitis.

Methods:

Review of medical charts of all adult patients hospitalised for community-acquired cellulitis (Jan 95–Dec 02) who had blood cultures performed on admission. Cellulitis complicating diabetic foot ulcers, orbital cellulitis, HIV-infected patients, and drug addicts were excluded. For the purpose of the study, patients with bacteraemia were compared with patients without bacteraemia.

Results:

There were 329 cases of cellulitis (184 female); mean age of 61.5 years. The infection was microbiologically documented in 115 cases (53 bacteraemia, 65 needle aspiration, and 20 surgical sample). The organisms isolated most frequently were Staphylococcus aureus 34, Streptococcus pyogenes 25, groups B, C, and G streptococci 19, Pseudomonas aeruginosa 14, and five Escherichia coli. Overall, 53 (16%) patients had bacteraemia and 276 patients had negative blood cultures. The development of in-hospital clinical complications (32% vs. 12%; P < 0.001) and overall mortality (<30 days) (19% vs. 2%; P < 0.001) were more frequent in patients with bacteraemia than in patients without bacteraemia. Factors significantly associated with bacteraemia by univariate analysis were: male sex (55% vs. 42%), age >60 years (77% vs. 56%), presence of multiple comorbidities (25% vs. 14%), duration of symptoms <2 days (54% vs. 33%), hypoalbuminaemia (<30 g/L) (46% vs. 28%), renal insufficiency (creatinine > 150 mmol/L) (25% vs. 6%), and shock (15% vs. 2%). Multivariate analysis identified age >60 years (OR 1.88), duration of symptoms <2 days (OR 2.19), and shock (7.58) as independent predictors of bacteraemia.

Conclusion:

The predictors of bacteraemia delineated in this study may help clinicians to identify a subset of patients with cellulitis at a high risk of complications and mortality.