Comparison of the Microbiology and Antibiotic Treatment between Diabetic and Non-Diabetic Patients Hospitalized with Acute Bacterial Skin and Skin Structure Infection
Methods: This was a secondary analysis of two published cohorts of patients hospitalized for otherwise uncomplicated cellulitis or abscess where complicated infections such as osteomyelitis or infected diabetic ulcers were excluded. The microbiology and antibiotic utilization were compared among diabetics and non-diabetics. Broad gram-negative therapy was defined as use of fluoroquinolones, β-lactamase inhibitor combinations, carbapenems, 2nd-5thgeneration cephalosporins, or aminoglycosides. Logistic regression was performed to identify factors associated with use of broad gram-negative therapy.
Results: Of 770 patients with cellulitis or abscess, 167 (22%) had diabetes mellitus. Diabetics were more likely to have cellulitis as the presenting infection (67% vs 56% of cases, p = .008). Of cases with a positive culture, an aerobic gram-positive organism was isolated in 92% of diabetics and 93% of non-diabetics (p = .79). Aerobic gram-negative organisms were isolated in 6% of diabetics and 11% of non-diabetics (p = .26). These comparisons were similar when stratified by cellulitis versus abscess. Despite the similar microbiology, diabetics were more likely to be treated with broad gram-negative therapy (45% vs 33% of cases, p = .003). By logistic regression, diabetes mellitus was independently associated with use of broad gram-negative therapy (OR 1.69, 95%CI 1.15 – 2.49).
Conclusion: Compared with non-diabetics, diabetics hospitalized with cellulitis or abscess were not more likely to have gram-negative pathogens; however, they were more likely to be treated with broad gram-negative therapy. Although a limitation of this type of analysis is that most cases of ABSSSI do not involve positive cultures, these findings suggest diabetics with otherwise uncomplicated cellulitis or abscess do not need broad gram-negative therapy.
S. J. Moore, None
B. Mccollister, None
C. Saveli, None
S. Pawlowski, None
D. Perlman, None
W. Burman, None