Artifactual Hypoglycaemia in Systemic Sclerosis and Raynaud’s Phenomenon: A Clinical Case Report and Short Review

Abstract

Background. Artifactual hypoglycaemia, defined as a discrepancy between glucometer (capillary) and plasma glucose levels, may lead to overtreatment and costly investigations. It is not infrequently observed in patients with Raynaud's phenomenon due to vascular capillary distortion, yet this is clinically underappreciated. Case Report. We report a 76-year-old woman with systemic sclerosis and Raynaud's phenomenon, who presented with upper gastrointestinal bleeding and found to have concomitant persistent hypoglycaemia (1.0–2.7mmol/L) on a point-of-care glucometer in the absence hypoglycaemic symptoms. She underwent a 2-week hospital admission, repeated glucose monitoring, hydrocortisone replacement and dextrose infusions, with consequent hyperglycaemia on plasma measurements. Clinically, she did not satisfy Whipple's triad and radiological investigations failed to identify pituitary or pancreatic pathology. A 72-hour fast was negative for hyperinsulinaemia or exogenous insulin use and her sulphonylurea metabolite urinary screen was negative. Discussion. Treatment of low capillary blood glucose is usually met with clinical impetus to treat, even when hypoglycaemic symptoms are lacking. The correct diagnosis may have been achieved had there been an observation of her cold hands, scleroderma facies, and consideration of the likely distorted peripheral microvasculature. Early identification of this presumably rare clinical scenario may have prevented overtreatment, altered methods of monitoring, and avoided unnecessary investigations.

Case Report: Artifactual Hypoglycemia: A Condition That Should Not Be Forgotten

“…Other conditions such as leukemia could also lead to artifactual hypoglycemia due to increased glycolysis by leukocytes (7).…”

<p>Hypoglycemia After Upper Gastrointestinal Surgery: Clinical Approach to Assessment, Diagnosis, and Treatment</p>

“…62 Venous glucose levels are required to establish the diagnosis, as capillary glucose measurements can be falsely low in the setting of relative hypotension or Raynaud's disease. [63][64][65] This is an essential element of diagnosis of PBH, and is needed to help distinguish from symptoms of dumping syndrome. Once hypoglycemia is established, differential diagnoses include malnutrition, side effects of medications or supplements, critical illness, hormone deficiencies (eg, adrenal), autoimmune hypoglycemia, insulinoma/ proinsulinoma, 66 or nonislet cell tumors.…”

Artifactual hypoglycaemia in a patient with scleroderma and Raynaud’s phenomenon

“…Whipple's triad confirms true hypoglycaemia and includes the following criteria: typical symptoms of hypoglycaemia, with low plasma glucose measured at the time of the symptoms, and relief of these symptoms when the glucose is raised to a normal level. [1] Clinically relevant hypoglycaemia is defined as a blood glucose <3.0 mmol/L, while levels <3.9 mmol/L should be regarded as a cautionary signal. [2] Plasma glucose levels measured at the same time as point-of-care glucose levels were normal.The mechanism of artifactual hypoglycaemia can be explained by progressive obliteration of the capillary microcirculation; therefore, the blood flow in the utmost distal parts of the fingers becomes compromised, which leads to false low readings on glucometers.…”