510. The accuracy of a diagnosis of “cellulitis” among hospitalized patients
Session: Poster Session: Hospital-acquired and Transplant Infections
Friday, October 30, 2009: 12:00 AM
Room: Poster Hall A
Backgroung: Cellulitis, a common skin and soft tissue infection, can be rapidly progressive and lead to hospitalization. Clear diagnostic guidelines defining cellulitis are lacking. Developing a structured approach to diagnosis may reduce misdiagnoses and prevent unnecessary antibiotic administration and hospitalization.
Methods: Two similar prospective studies were performed between April 2007 and January 2009 (University of Rochester, NY and Harbor-UCLA Medical Center, CA). Patients hospitalized for cellulitis were enrolled and examined by an attending dermatologist or an infectious disease specialist; their diagnosis was considered the gold standard. Patients determined not to have skin infections were considered misdiagnosed.
Results: Among 145 patients enrolled, cellulitis misdiagnosis was 20% at one center and 36% at the other. Misdiagnosed cases were diagnosed by the specialists as stasis dermatitis (37%), non-specific dermatitis (5%), thrombophlebitis (5%), trauma (5%), or other non-infectious skin conditions (52%). Tenderness, swelling, elevated white blood cell count (WBC) and tactile warmth of the involved area were associated (p < 0.05) with cellulitis. Lack of elevated WBC and lack of warmth were independent predictors (p < 0.005) of cellulitis misdiagnosis in a multivariate model.
Conclusions: We found that 20-36% of cellulitis diagnoses made by admitting physicians were non-infectious skin conditions. Lack of elevated WBC and lack of tactile warmth were independently associated with a misdiagnosis of cellulitis. A structured approach to cellulitis diagnosis may enhance diagnostic accuracy, improve patient safety, reduce health care cost, and minimize unnecessary antibiotic use.
Sandy Chira, BS1, Noah Craft, MD, PhD, DTM&H1, Consuelo David, BA2, Samantha Eells, MPH1, Manasi Ladrigan, MD3, Loren Miller, MD, MPH, Art Papier, MD3 and  C. David, None..
S. Chira, None..
S. Eells, None..
M. Ladrigan, None..
A. Papier, None. 
L. G. Miller,
Pfizer Role(s): Grant Investigator, Grant Investigator, Grant Investigator, Received: Research Grant.
Cubist Pharmaceuticals Role(s): Grant Investigator, Grant Investigator, Grant Investigator, Received: Grant Recipient.
N. Craft, None., (1)Los Angeles Biomedical Research Institution at Harbor-UCLA Medical Center, Torrance, CA, (2)Los Angeles Biomedical Research Institute, Torracne, CA, (3)Univ. of Rochester, Rochester, NY

Disclosures:

S. Chira, None

N. Craft, None

C. David, None

S. Eells, None

M. Ladrigan, None

L. Miller, None

A. Papier, None