Central pontine myelinolysis

Rapid correction may result in cerebral edema, seizures, central pontine myelinolysis, or death... 

Treatment of hyponatremia involves the use of hypertonic saline. However, care is required since correction at rates in excess of 1 mEq/l/h may result in central pontine myelinolysis (CPM) [5], Symptoms of CPM include progressive weakness leading to quadriparesis, pseudobulbar palsy and altered mental status. CPM is often fatal and is characterized neuropathologically by demyelinating lesions in the central pons. 

CPM central pontine myelinolysis FRET fluorescence resonant energy transfer... 

Hong, J.-J., Lin, J.-L., Wu, M.-S., Huang, C.-C. Verberckmoes, R. (1996) A chronic glue sniffer with hyperchloraemia metabolic acidosis, rhabdomyolysis, irreversible quadriplegia, central pontine myelinolysis, and hypothyroidism. Nephrol. Dial. Transpl., 11, 1848-1849... 

Central pontine myelinolysis, characterized by progressive bulbar weakness and quadriparesis. 

A variety of tumours, e.g. oat-cell limg cancer, can make vasopressin, and of course they are not subject to normal homeostatic mechanisms. SIADH also occurs in some CNS and respiratory disorders (infection). Dilutional hyponatraemia follows, i.e. low plasma sodium with an inappropriately low plasma osmolality and high urine osmolality. When the plasma sodium approaches 120 mmol/I treatment should be with fluid restriction (< 500 ml/day). Treatment is primarily of the imderlying disorder accompanied by fluid restriction. Chemotherapy to the causative tumour or infection is likely to be the most effective treatment. Demeclocycline, which inhibits the renal action of vasopressin, is useful Infusion of isotonic or hypertonic saline must be reserved for extreme emergencies, associated with stupor, and undertaken with great caution. Rapid correction of hyponatraemia must be avoided because of the risk of central pontine myelinolysis the rate of correction must not exceed 12 mmol/1 per 24 h. 

Central pontine myelinolysis has been reported in patients given intravenous saline (2). Pontine and extrapontine myelinolysis are generally considered to be linked with rapid correction of severe hyponatremia, for example in the treatment of hyponatremia in patients with so-called hyperosmolar non-ketoacidotic hyperglycemia reference. Neurological deterioration is likely to result. It is not certain what rate of sodium repletion is safe. The best data available suggest that correction should not exceed 12 mmol/1 per day, although more rapid correction may be safe. The duration of treatment also seems to be important 12 mmol/1 per day may be excessive if continued for more than 2 or 3 days. 

Treatment of hyponatremia. Treatment depends on the cause, the patient s volume status, and most important, the patient s clinical condition. Caution Avoid overly rapid correction of the sodium, because brain damage (central pontine myelinolysis) may occur if the sodium is increased by more than 25 mEq/L in the first 24 hours. Obtain frequent measurements of serum and urine sodium levels and adjust the rate of infusion as needed to inorease the serum sodium by no more than 1-1.5 mEq/h. Arrange consultation with a nephrologist as soon as possible. For patients with profound hyponatremia (serum sodium < 110 mEq/L) accompanied by coma or seizures, administer hypertonic (3% sodium chloride) saline, 100-200 mL. 

The exact nature of pontine lesions classified as capillary malformations will remain speculative in the vast majority of patients. Beside vascular malformations, the differential diagnosis of an enhancing pontine lesion might include neoplasm, demyelin-ating disease, infection, infarction, or, rarely, central pontine myelinolysis. The absence of mass effect or significant T2 prolongation, however, argues... 

Bejot Y, Depierre P, Osseby GV, Troisgros O, Moreau T, Giroud M. Central pontine and extra-pontine myelinolysis a complication of lithium toxicity in a pregnant woman. Clin Neurol Neurosurg 2008 110(8) 852-. ... 

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