Although rare, insulinomas are often considered by physicians dealing with patients who present with hypoglycemic symptoms. Insulinomas are the most common functioning endocrine neoplasms of the pancreas, with an estimated incidence of 1-4 cases per million population per year. Less than 10% are reported to metastasize.
In patients with insulinoma, episodes of hyperinsulinemic hypoglycemia cause various adrenergic and neuroglycopenic symptoms that usually emerge in the fasting state. Another clinical characteristic of patients with insulinomas is weight gain due to frequent eating in order to prevent hypoglycemic events. Although the patient in this case experienced symptomatic hypoglycemic events that respond to food, he never demonstrated objective evidence of low blood sugar. Absence of the Whipple triad rendered further workup for insulinoma inappropriate.
Hyperviscosity syndromes should be included in the differential diagnoses of patients with hypoglycemic episodes. On the basis of the history and detailed laboratory data, the patient in this case did not have polycythemia or leukemia. Moreover, he was evaluated with multiple laboratory readings, which failed to show any blood glucose level < 70 mg/dL.
The other differential diagnosis to consider in this clinical scenario is hypogonadism. Although hypogonadism usually presents with fatigue and low libido, some patients can present with flushing and mood alterations. The patient in this case never complained of low libido. Hypogonadism is not related to hypoglycemia or pseudohypoglycemia. This patient had a high risk for hypogonadism due to the exogenous supplements that he was using to increase his muscle mass. However, further workup on this patient yielded normal testosterone, follicle-stimulating hormone, and luteinizing hormone levels.
The patient did not have typical symptoms of Raynaud phenomenon, and his physical examination did not support any connective tissue disorder. Workup was not initiated for connective tissue disorders because the possibility of these disorders presenting with only symptoms of hypoglycemia is highly unlikely. The patient's history also clearly included that he never had any issues with the weather changes. Acrocyanosis and Eisenmenger syndrome can be ruled out because he never had issues with skin color changes and could perform regular high-intensity exercise without any issues.
The effect of drugs on the patient's blood glucose levels was not an appropriate differential diagnosis in this case because such substances as high-dose vitamin C, dopamine, mannitol, and acetaminophen falsely lower blood glucose levels beyond normal readings. This patient never had blood glucose levels < 70 mg/dL; thus, drug-induced pseudohypoglycemia was ruled out. Other less possible causes of severe acidosis and high-flow oxygen were not appropriate for this patient because he was not critically ill.
The patient in this case was instructed to stop taking supplements and injections and was referred for a detailed psychiatric evaluation. His symptoms of hypoglycemia disappeared after receiving treatment from his psychiatrist for 8 months.
Medscape © 2021 WebMD, LLC
Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.
Cite this: Ricardo Correa, Sri Harsha Tella. A Weightlifter With Palpitations, Tremors, and Confusion - Medscape - Jan 11, 2021.