Prevalence of concurrent deep vein thrombosis in patients with lower limb cellulitis: a prospective cohort study

BACKGROUND Lower limb cellulitis and deep vein thrombosis share clinical features and investigation of patients with cellulitis for concurrent DVT is common. The prevalence of DVT in this group is uncertain. This study aimed to determine the prevalence of deep vein thrombosis (DVT) in patients with lower limb cellulitis and to investigate the utility of applying the Wells algorithm to this patient group. METHODS Patients admitted with lower limb cellulitis prospectively underwent a likelihood assessment for DVT using the Wells criteria followed by investigation with D-dimer and ultrasonography of ipsilateral femoral veins as appropriate. Diagnoses of contralateral DVT or pulmonary embolism during admission were recorded. RESULTS 200 patients assessed for DVT. 20% of subjects were high risk by Wells criteria. D-dimer was elevated in 74% and 79% underwent insonation of the affected leg. Ipsilateral DVT was found in 1 patient (0.5%) and non-ipsilateral VTE in a further 2 (1%). CONCLUSIONS Deep vein thrombosis rarely occurs concurrently with lower limb cellulitis. The Wells score substantially overestimates the likelihood of DVT due to an overlap of clinical signs. Investigation for DVT in patients with cellulitis is likely to yield few diagnoses and is not warranted in the absence of a hypercoaguable state. TRIAL REGISTRATION ACTRN: 12610000792022 (https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=320662).