Refractory hypoglycemia as the presenting sign of Wilms tumor in a child: A case report

Introduction

Wilms tumor, or nephroblastoma, most commonly presents in children as an asymptomatic abdominal mass and less commonly as hematuria or hypertension. Symptomatic hypoglycemia associated with Wilms tumor is rare and has only been reported in one previous case, even though insulin-like growth factor-2 (IGF-2) overexpression is the most common genetic alteration in this tumor.

Case presentation

A 4-year-old male was brought to the Emergency Department after multiple episodes of unresponsiveness and self-limited seizure activity. On arrival his blood glucose was 25 mg/dL. He was treated with glucagon, a dextrose 10 % (D10) bolus and placed on D10 maintenance fluid. Despite these measures his glucose continued to drop. During his hypoglycemia treatment, he underwent an abdominal ultrasound which showed a large right renal mass. A subsequent computerized tomography (CT) of the abdomen and pelvis showed a 13.9 x 10.4 × 13.0 cm multilobulated right renal mass. Due to the suspicion that the tumor could be the cause of the refractory hypoglycemia, he was taken to the operating room the following day and underwent an uneventful right radical nephrectomy with regional lymphadenectomy. Immediately after the operation his blood glucose increased to 232 mg/dL, and it remained between 90 and 117 mg/dL throughout his recovery. He did well post operatively and was discharged home on postoperative day 6. The pathology was consistent with a 1026-g Wilms tumor with gain of 1q, loss of 2q36 and 9q, but no abnormalities detected in chromosome 11. He subsequently underwent chemotherapy with vincristine, dactinomycin and doxorubicin for 24 weeks, along with 6 cycles of radiation for Stage III disease. He was lost to follow up before the last schedule chemotherapy dose. He returned to the hospital with abdominal pain a few months later. Multiple metastases were found in the spleen, liver and peritoneum. He is currently undergoing further chemotherapy, but his hypoglycemia remains resolved.

Conclusion

Children with unexplained persistent hypoglycemia should be screened for abdominal tumors. Although rarely reported, tumors that are related to over-secretion of IGF-2 can cause refractory hypoglycemia and must be promptly resected.