Hypoglycemic hemiplegia: a case study

Neurologic damage in hypoglycemia

Hypoglycemia occurs in diabetic patients as a consequence of treatment with hypoglycemic agents, in insulinoma patients as a result of excessive insulin production, and in infants as a result of abnormal regulation of metabolism. Profound hypoglycemia can cause structural and functional disturbances in both the central (CNS) and the peripheral nervous system (PNS). The brain is damaged by a short and severe episode of hypoglycemia, whereas PNS pathology appears after a mild and prolonged episode. In the CNS, damaged mitochondria, elevated intracellular Ca2(+) level, released cytochrome c to the cytosol, extensive production of superoxide, increased caspase-3 activity, release of aspartate and glutamate from presynaptic terminals, and altered biosynthetic machinery can lead to neuronal cell death in the brain. Considering the PNS, chronic hypoglycemia is associated with delayed motor and sensory conduction velocities in peripheral nerves. With respect to pathology, hypoglycemic neuropathy in the PNS is characterized by Wallerian-like axonal degeneration that starts at the nerve terminal and progresses to a more proximal part of the axon, and motor axons to the muscles may be more severely damaged than sensory axons. Since excitatory neurotransmitters primarily involve the neuron in the CNS, this "dying back" pattern of axonal damage in the PNS may involve mechanisms other than excitotoxicity.

Multi-modal brain imaging showing brain damage to the orbitofrontal cortex and left hemisphere, in a case of prolonged hypoglycemia-induced transient hemiplegia followed by persistent encephalopathy

A 21-year-old left-handed male patient was admitted with a 19-h history of coma after substantial insulin injection for suicide attempt. Although the patient recovered from coma 3 days after injury, he experienced transient hemiplegia followed by permanent brain damage. Electroencephalogram (EEG), brain magnetic resonance imaging (MRI), and brain single-photon emission computed tomography (SPECT) identified the localization of this dysfunction, but consistency between clinical symptoms and brain images changed depending on the course of treatment. Transient hemiplegia corresponded to abnormal waveforms on EEG and decreased cerebral blood flow on SPECT, whereas persistent dysfunctions corresponded to abnormal brain regions on MRI and SPECT.

A case of hypoglycemic hemiparesis and literature review

An 89-year-old man with diabetes treated with metformin 500 mg/day and glimepiride 4 mg/day was hospitalized because of hypoglycemic right hemiparesis and dysarthria (casual glucose value 1.8 mmol/L), which resolved quickly following administration of 40 mL of 40% dextrose. Hemiparesis is a rare symptom (4.2%) of hypoglycemia. There are about 200 case reports of hypoglycemic hemiparesis. The average glucose level at which hemiparesis developed was 1.8 mmol/L. Right-sided hemiparesis predominated (R 66%; L 34%). On imaging studies, abnormal findings were frequently observed in the internal capsule or splenium of the corpus callosum. The mechanism of hemiparesis is not fully understood. The existence of cases in which hypoglycemia cannot be distinguished from stroke on imaging studies suggests the importance of measurement of the blood glucose level when the symptoms of stroke are first recognized.

Acute brain injury in hypoglycaemia-induced hemiplegia

BACKGROUND

The development of hemiplegia as a result of hypoglycaemia was first described in 1928. However, the mechanism remains unclear.

CASE REPORT

We report a case of a 58-year-old male with diabetes, who developed left hemiplegia during a severe hypoglycaemic event. Results Diffusion-weighted magnetic resonance imaging detected an increased signal intensity in the pons, indicating that the patient's hemiplegia resulted from acute brain injury.

CONCLUSIONS

This report provides evidence that acute brain injury may be a cause of the neurological deficit.

Recurrent hypoglycemic hemiparesis and aphasia in an adolescent patient

A 12-year-old diabetic female with right-side hemiparesis and aphasia occurring after a hypoglycemic episode is reported. Her clinical course improved over a 24-hour period, and further investigation revealed only electroencephalographic slowing, which was more prominent on the left. Ten months later, she had a recurrence of the same symptoms, which also resolved rapidly. This potential complication of hypoglycemia is often mistaken for a cerebrovascular accident.

[Diagnostic pitfalls in sulfonylurea-induced neuroglycopenic syndrome with hemiparesis, dysphasia and somnolence]

BACKGROUND

The neuroglycopenic syndrome, which is often due to sulfonylurea-induced hypoglycemia, is frequently overlooked or misinterpretated as cerebral ischemia.

PATIENTS

Two women aged 81 and 83 years, respectively, with type II diabetes treated with sulfonylureas presented with hemiparesis, dysphasia and somnolence. Both, general practitioner and emergency room physician first interpretated the symptoms as clinical signs of stroke without determination of blood glucose. After hours of delay due to unnecessary and expensive examinations including cerebral computed tomography the correct diagnosis of hypoglycemia was finally made. After injection of i.v. glucose the symptomatology was completely reversible.

CONCLUSION

In every case of disturbance of consciousness, acute neurologic deficits and psychiatric abnormalities an immediate blood glucose test should be performed to exclude hypoglycemia.