7484 Pseudohypoglycemia In A Patient With Raynaud’s Phenomenon

Abstract

Abstract Disclosure: J. Fedorko: None. P. Subarajan: None. A.P. Amblee: None. C.A. Poku: None. Background: The term ‘pseudohypoglycemia’ is used to describe the disparity between actual and measured capillary glucose and clinical presentation. It has been used to describe situations when a patient has the characteristic symptoms of low blood glucose (BG) Whipple’s triad), but the patient’s BG levels are within normal limits. Alternatively, this term can also be used to describe falsely low BG levels on finger-stick (capillary) readings in a patient with normal serum glucose levels and without the characteristic Whipple’s triad. Case: A 55-year-old female with Raynaud’s phenomenon was seen in Endocrine clinic with persistent hypoglycemia noted on finger-stick glucose readings. Her finger-stick glucose reading was 43, and was subsequently given 24 grams of glucose gel. Ten minutes later, a repeat finger stick BG was 44. She had no weakness, tremors, shakiness, vision changes, confusion, seizures, lightheadedness, dizziness, tachycardia, palpitations, nervousness, hunger, paresthesias irritability, confusion, seizures, loss of consciousness, or any other symptoms or signs of hypoglycemia. She had no such previous episodes and her fasting BG ranged from mid-70s to 80, with post-meal BG ranging from 100 to mid-100’s. Her most recent hemoglobin A1c was 5.5. She regularly experiences cyanosis of fingers consistent with Raynaud’s phenomenon, triggered by cold air in winter and air conditioners in summer. She does not take any medications for these episodes. Given the absence of classic Whipple triad and normal BG from peripheral blood draw, the patient’s low finger stick BG readings were attributable to Raynaud’s phenomenon. It is postulated to be secondary to decreased perfusion in the digital microcirculation and increased blood transit time in the fingers, resulting in a local increase in glucose consumption and thus low capillary finger stick BG levels. Simultaneously done serum glucose levels are usually normal. Conclusion: Pseudohypoglycemia can occur in patients with impaired peripheral circulation such as Raynaud’s phenomenon, acrocyanosis, peripheral vascular disease, shock, or with increased glycolysis by blood cells like in leukemia, polycythemia and rare infections like African trypanosomiasis, hyperviscosity syndromes like Waldenstrom’s and monoclonal gammopathy of undetermined significance. In patients with low finger-stick (capillary) glucose levels who do not display Whipple’s triad, and have comorbid conditions that might interfere with the BG reading, it is important for clinicians to recognize the difference between true and pseudohypoglycemia. This can be confirmed with a simultaneously done normal serum glucose level and will prevent unnecessary investigations or excessive treatment. Presentation: 6/3/2024