Acute lower extremity (LE) cellulitis often presents with swelling and erythema. In many cases this leads hospitalists to work up the patient for concurrent deep venous thrombosis (DVT). No previous studies have looked specifically at whether clinical features alone can be used to rule out DVT in the presence of clinical LE cellulitis. We investigated if clinical features and routine laboratory results can be used to rule out DVT in the presence of LE cellulitis.
We retrospectively examined charts of patients admitted through the emergency department (ED) between January 2000 and July 2005 with a suspected diagnosis of LE cellulitis who also had a duplex ultrasound of the LE. The primary outcome was the finding of a DVT on duplex ultrasound on admission. We explored the association between this primary outcome and 3 clinical features of LE cellulitis: erythema, white blood cell count (WBC), and fever. We also explored whether the association was affected by medical risk factors for DVT.
Reviewed were the charts of a total of 245 patients, 46.3% of whom were female. Their mean age was 57.48 ± 18 years. Thirty‐one patients (12.7%) were found to have a DVT on admission. The presence of erythema on admission was found to predict the absence of DVT (OR = 3.6 [range: 1.57‐8.3], P = .04).The risk factors significantly associated with the presence of DVT were chronic lung disease (OR = 2.495 [range: 1.05‐5.9], P = .037) and history of DVT (OR = 4.5 [range: 1.9‐11], P = .001). WBC count and fever were not found to be significantly associated with the presence or absence of a DVT. If a patient presented to the ED with erythema, the risk of concurrent DVT was 9.8%. If a patient presented with erythema and no history of DVT, the risk was 7.8%, and with erythema without chronic lung disease, the risk was 6.2%. If a patient with LE cellulitis presented with a history of DVT, the risk of a new, concurrent DVT was 33%; if a patient had no erythema, the risk was 66%. A patient presenting with erythema and a WBC of more than 10,000/μL had a significantly higher chance of not having a DVT than with a WBC of more than 10,000/ μL or erythema alone (OR = 3.8 [range: 1.4‐10.1], P = .006), with a 5.3% incidence of DVT
In this retrospective study, the combination of erythema and a WBC count of more than 10,000/ μL helped in predicting the absence of concurrent DVT in patients with LE cellulitis. However the negative predictive value was not high enough to confidently rule out DVT. Prospective studies should be performed to evaluate if clinical features can predict the presence or absence of DVT in LE cellulitis
A. Chaaya, None; J. Rachoin, None; E. Cerceo, None; E. Kupersmith, Merck, consulting fees or other remuneration (payment); sanofi‐aventis, research grants; sanofi‐aventis, consulting fees or other remuneration (payment); Pfizer, consulting fees or other remuneration (payment); G. Newell, None.