Refractory paraneoplastic hypoglycemia secondary to a large renal solitary fibrous tumor in a 10-year-old female: a case report

Introduction: Non-islet cell tumor hypoglycemia (NICTH) in pediatric patients is an uncommon phenomenon often presenting with neuroglycopenic symptoms with further workup identifying a mass. Renal solitary fibrous tumors in pediatric patients as the etiology of this paraneoplastic syndrome is exceedingly rare. Case presentation: A 10-year-old female presented with neuroglycopenic symptoms and hypoglycemia that was refractory to oral glucose. After correction of hypoglycemia with a dextrose 50% (D50) bolus and maintenance dextrose 10% normal saline (D10NS) infusion further workup with computed tomography identified a large 15 cm right renal mass without evidence of metastatic disease. Insulin-like growth factor-1 and 2 levels were found to be low. The patient underwent en bloc resection of the mass and kidney which was uncomplicated. Pathology was consistent with a solitary fibrous tumor without extracapsular invasion. Post-operatively, the patient was weaned off of dextrose infusions and returned to normoglycemia on a regular diet within twoh days. She underwent adjuvant chemotherapy with vincristine, doxorubicin, and cyclophosphamide. At 3-month follow up, the patient continues to be normoglycemic without evidence of metastasis or local recurrence. Conclusion: Renal solitary fibrous tumors should be included in the differential diagnosis of children who develop unexplained refractory hypoglycemia.