Background: Role of Ddimer assay in suspected high risk obese patients has not been explored much. Therefore, purpose of this study is to ascertain the place of Ddimer assay in diagnosis of Deep vein thrombosis (DVT) in obese patients.

Methods: Patients attending outdoor or admitted in surgery ward of hospital, presenting with history and examination suggestive of DVT, at high risk of developing DVT and having Body Mass Index >25 kg/m2 were included. Ddimer assay and ultrasonography (USG) was done at the time of admission, ultrasound was repeated at one week (if the first examination was negative for DVT) and at one month. Out of total 70 suspected cases, Ddimer levels were compared in relation to cases which were finally diagnosed as DVT by USG and those in whom DVT was excluded. Sensitivity, specificity, positive predictive value, and negative predictive value for the Ddimer test were calculated.

Results: 70 suspected cases of DVT (32 males & 38 females) were included with mean age of 55.59±13.59 y and with mean BMI of 27.7±1.7. No statistical difference between vital parameters of diagnosed and excluded cases of DVT was found. The sensitivity and specificity of D dimer were found to be 100.0% & 35.5% respectively. Positive predictive value was 46.29% and Negative predictive value was 100.0%.

Conclusions The sensitivity and negative predictive value of semiquantative latex Ddimer assay for deep venous thrombosis are high. Deep vein thrombosis in obese individuals can be ruled out on the basis of Ddimer assay.