INTRODUCTION: Mondor disease (MD), a superficial thrombophlebitis of the 
thoraco-epigastric veins and their confluents is rarely reported in the 
literature. The superior epigastric vein is the most affected vessel but 
involvement of the inferior epigastric vessels or their branches have also been 
described. There is no universal consensus on treatment in the literature but 
most authors suggest symptomatic treatment with non-steroid anti-inflammatory 
drugs (NSAIDs).
CASE REPORT: We report the case of a marathon runner who presented with right 
iliac fossa pain mimicking the clinical symptomatology of an acute appendicitis. 
The history and the calculated Alvarado score were not in favor of an acute 
appendicitis. This situation motivated multiple investigations and we finally 
arrived at the diagnosis of MD.
DISCUSSION: Acute appendicitis (AA) is the most common cause of surgical 
emergencies and one of the most frequent indications for an urgent abdominal 
surgical procedure around the world. In some cases, right lower quadrant pain 
remains unclear in spite of US, CT scan, and exclusion of urological and 
gynecological causes, thus we need to think of some rare pathologies like MD.
CONCLUSION: MD is often mentioned in the differential diagnosis of breast 
pathologies but rarely in abdominal pain assessment. It should be mentioned in 
the differential diagnosis of the right lower quadrant pain when the clinical 
presentation is unclear and when acute appendicitis has been excluded. Awareness 
of MD can avoid misdiagnosis and decrease extra costs by sparing unnecessary 
imaging.