Abstract
Inflammatory bowel disease (IBD) is a chronic disorder of the gastrointestinal tract, with a rising incidence worldwide. It is often associated with numerous extraintestinal manifestations, such as erythema nodosum (EN) and venous thromboembolism (VTE). We report a case of a 17-year-old male seen in a Pediatric consultation due to pain at the inner aspect of the lower left limb associated with bilateral lower limb cutaneous lesions for about a year. A left leg ultrasound revealed signs of phlebitis and the doppler ultrasonography revealed signs of an old occlusive VTE at the level of the great left saphenous vein. Fecal calprotectin was significantly elevated (775 ug/g). Abdominal ultrasound and entero-MRI showed increased thickness of the terminal ileum. Colonoscopy confirmed the diagnosis of Crohn's disease. He began induction treatment with systemic corticosteroids for eight weeks and maintenance treatment with azathioprine. Three months later he was asymptomatic with complete resolution of the erythema nodosum lesions. Extraintestinal manifestations can precede or be concomitant with the diagnosis of IBD and can have a significant impact on the quality of life of these patients. EN is the most common skin manifestation of IBD, with a well-established relationship between these two diseases. Many other extraintestinal manifestations are described, occurring less frequently. The authors aim to bring awareness to the risk of VTE as a rare but non-negligible comorbidity of IBD. This was an uncommon initial presentation of Crohn’s Disease since the patient had never reported any gastrointestinal symptoms. It is important to improve the knowledge of pediatricians about all kinds of extraintestinal manifestations of IBD since they may guide toward the correct diagnosis and allow the prompt initiation of treatment.

Key words: inflammatory bowel disease, venous thromboembolism, erythema nodosum, gastrointestinal