Case Presentation: An eight-year-old girl presented with acute onset of dragging her left foot that quickly progressed to left sided hemiplegia with confusion and decreased vocalization. She had episodic hematochezia and abdominal pain for 6 months prior and was hospitalized for rehydration secondary to these symptoms one week before presentation.Her temperature was 38.2C with blood pressure 123/84 (above the 95th percentile), and heart rate 118. She needed stimulation to stay awake and was nonverbal but could follow commands. She had a right lateral gaze palsy and flaccid paralysis in the left upper and lower extremities. Abdomen was soft and non-distended, with mild, diffuse tenderness to palpation. WBC count was 22 k/uL with normal hemoglobin and platelets of 165 k/uL. CRP was 71.5 mg/L and ESR 78 mm/hr. INR was 1.2 with PTT 33 sec and D-dimer >20.0 ug/mL. Atypical P-ANCA was positive and COVID-19 PCR was negative. CT venogram showed cerebral venous sinus thromboses (CVST) and intraparenchymal and subarachnoid hemorrhages within the right frontal and occipital lobes with associated edema. Considering the history of hematochezia with elevated inflammatory markers and P-ANCA, inflammatory bowel disease (IBD) coupled with dehydration likely led to CVST and venous hemorrhagic strokes. Her elevated blood pressures were likely secondary to increased intracranial pressure. She was treated with heparin and transitioned to enoxaparin after improvement of intracranial hemorrhages. Following neurological stabilization, she underwent EGD and colonoscopy. Histology and pathology were consistent with indeterminate colitis. She was started on adalimumab with improvement in symptoms but continues to have frequent hospitalizations for flares.

Discussion: The most common inciting factors for CVST in children are otitis media, mastoiditis and dehydration. Rarely, chronic inflammatory conditions (as in our patient) can be responsible. IBD, particularly ulcerative colitis, is a known risk factor for hypercoagulability, leading to an approximate three-fold increase in venous thrombosis events in adults; data is more limited in children but the available literature supports a similar increased risk. Anemia and steroid use, both common in patients with IBD, are also independent risk factors associated with CVST. Early diagnosis and good disease control are the mainstay of prevention of CVST in IBD patients, as there is a lower risk of thromboembolic events in remission. Anti-TNF alpha inhibitors, including adalimumab, have been shown to decrease thromboembolic risk in adults. Prophylactic anticoagulation is recommended routinely in adults hospitalized for IBD flares, but no studies exist to support such a recommendation in pediatric patients. The treatment of pediatric patients with CVST regardless of cause consists of anticoagulation for a minimum of three months with heparin transitioned to enoxaparin or warfarin (or potentially a direct-acting oral anticoagulant in the future).

Conclusions: CSVT should be considered in any pediatric patient presenting with stroke-like symptoms, and anticoagulation should be started immediately after diagnosis. Early diagnosis of IBD (including close attention to red flag symptoms like hematochezia) is vitally important to decrease the risk for thromboses. Venous thromboembolism prophylaxis should be considered in high-risk pediatric patients with IBD, with further study needed.