Backgound: Presentation of acute appendicitis may be typical or atypical depending upon clinical signs and symptoms. Atypical features may pose a diagnostic challenge. It is imperative during clinical evaluation of an atypical presentation; we consider other conditions that might mimic acute appendicitis. Case Report: We report the unique case of a 25 year old man who presented with typical signs and symptoms of acute appendicitis in whom a subsequent diagnosis of thrombosis of the common femoral vein secondary to congenital anomalies of inferior vena cava (IVC) was made. Conclusions: In patients with atypical symptoms, deep venous thrombosis (DVT) must be actively looked for and thus may avoid an unnecessary operation. Deep venous thrombosis should be considered as a rare possibility in the differential diagnosis of acute appendicitis to avoid unnecessary intervention.