SAT140 A Rare Case Of Asymptomatic Severe Refractory Hypoglycemia Due To Hyper-Warburgism In A Young Patient With T-cell Acute Lymphoblastic Leukemia (ALL)

Abstract

Abstract Disclosure: S. Choe: None. Background: Hyper-Warburgism, exaggerated Warburg effect, is a rare but serious paraneoplastic syndrome caused by excess glucose consumption by cancer cells through glycolytic pathway leading to lactic acidosis and treatment refractory hypoglycemia. Neuroglycopenic symptoms are absent in these patients hence patients do not meet Whipple triad. Clinical Case: A 33yo African American male with past medical history of recently diagnosed cardiomyopathy and atrial fibrillation was initially admitted to outside institution for cardiac ablation then subsequently transferred to our institution for escalation of care in the setting of post-procedural persistent hypoglycemia. He reported symptoms of fatigue and poor appetite. He noted an unintentional weight loss of 30lb over the past 2 weeks. However, he denied fever, night sweats, classic signs and symptoms of hypoglycemia. Vital signs and physical examination were unremarkable. Clinical manifestation of neuroglycopenia was absent despite serum glucose as low as 46 while serum lactate of 23.8 mmol/L (0.5-2 mmol/L). Initial laboratory test notable for lactic acid of 24.2 mmol/L, glucose of 57 mg/dL, bicarbonate of 12 mEq/L, anionic gap of 39 mEq/L, beta hydroxybutyrate of 5.3 mmol/L, IGF-1 of 192 ng/mL (75–212 ng/ml), IGF-II of 570 ng/mL (288–736 ng/ml), AM cortisol of 14.3 μg/dl, ACTH of 41.6 pg/ml, hemoglobin A1c of 4.8 %, fasting insulin of 1 IU/liter, C-peptide of 0.4 ng/ml, and pro-insulin of 2.9 pg/ml. Given suppression of insulin and proinsulin levels and IGF-II level >275 ng/ml, noninsulin-mediated hypoglycemia was suspected. A CT of chest/abdomen/pelvis revealed a subpleural soft tissue mass involving the posterior mediastinum measuring 4.4 x 3.6 x 3.7 cm, diffuse bilateral renal involvement suspicious for renal lymphoma, adenopathy in the bilateral inguinal, axillary, and external iliac chains. Bone marrow biopsy was performed and result was consistent with T-cell ALL. 20% dextrose infusion was titrated up to keep his BG above 70 mg/dl and high dose steroids was initiated to bridge to chemotherapy. Chemotherapy was initiated soon after confirmation of diagnosis by bone marrow biopsy. The lactic acidosis and hypoglycemia dramatically improved shortly after. PET/CT done 4 weeks after first cycle of chemotherapy failed to identify active disease proving the patient’s good response to chemotherapy. Conclusion: The patient presented with noninsulin-mediated hypoglycemia due to rapid glucose use by cancer cell leading to hyper-Warburgism, evident by severe lactic acidosis, spontaneous hypoglycemia, and large tumor burden on CT scan. Absence of neuroglycopenia presumable due to brain using lactate as fuel and, for this reason, Whipple triad cannot be applied to diagnose hypoglycemia in this case. Chemotherapy must be initiated timely manner as it would resolve metabolic abnormalities dramatically as it was seen in our patient. Presentation: Saturday, June 17, 2023