hypoglycaemia-induced hallucination

   Hypoglycaemia is also written as hypoglycemia. Both terms stem from the Greek words hupo (below, beneath), gleukos (must), and haima (blood). They translate as 'low blood sugar'. The introduction of the term hypoglycaemia is commonly attributed to the American physician Seale Harris (1870-1957). After the discovery of insulin in 1921 by the medical scientists Frederick Grant Banting (1891-1941), John James Richard Mcleod (1876-1935), and Charles Herbert Best (1899-1978), Harris studied the effects of hyper-insulinism in 1923 and formulated his hypothesis of the hypoglycaemic attack. Hypoglycaemia is generally thought to be a rare condition, although certain authors suspect that it may be quite common. It is defined by a blood glucose level below the physiological threshold. That threshold is commonly cited as lying between 60 and 70 mg/dl, but for different populations and different clinical and research purposes, it may be 40, 50, or 60 mg/dl. The clinical presentation of hypoglycaemia in adults includes such diverse symptoms as fatigue, confusion, vertigo, nervousness, profuse sweating, tachycardia, mydriasis, ataxia, dysarthria, " paraesthesiae, headache, anxiety, negativism, irritability, and epileptic seizures. It may develop further into a hypoglycaemic coma and eventually death. Although descriptions of this clinical syndrome were not new, it was only after the introduction of insulin therapy that it became associated with low blood sugar. Etiologically, hypoglycaemia is associated primarily with an inadequate intake of carbohydrates and with insulin overdosage. It can be complicated by "simple or "geometric visual hallucinations, including "scintillating scotomata, and phenomena that comply with the "form constants as described by the German-American biological psychologist and philosopher Heinrich Klüver (1897-1979). These hypoglycaemia-induced hallucinations may or may not occur in the context of a "twilight state or an "aura preceding a hypoglycaemic epileptic seizure. Psychosis-like " auditory and " visual hallucinations have also been reported.

   References

   Chappuis, C. (1982). Halluzinationen bei internistischen, insbesondere geriatrischen Patienten.In: Halluzinationen bei Epilepsien und ihre Differentialdiagnose.Edited by Karbowski, K. Bern: Verlag Hans Huber.

   Harris, S. (1924). Hyperinsulinism and dysin-sulinism. Journal of the American Medical Association, 83, 729-733.

   Nakanishi, T. (1988). Visual hallucination without the disturbance of consciousness in hypo-glycaemic attack: Report of an unusual case. IgakuKenkyu, 58, 421-426.

   Neundörfer, B. (1973). Neuropsychiatrische Befunde in der Hypoglykämie. Deutsche Medizinische Wochenschrift, 14, 1722-1723.