Osmotic myelinolysis syndrome after treatment of severe deamino arginine vasopressin-associated hyponatraemia: pitfalls in emergency medicine

Extrapontine myelinolysis caused by rapid correction of pituitrin-induced severe hyponatremia: A case report

BACKGROUND

Severe hyponatremia is considered a rare complication of pituitrin, which is widely used for the treatment of pulmonary hemorrhage. However, the management of pituitrin-associated hyponatremia can be challenging because a rapid correction of hyponatremia may cause the development of osmotic demyelination syndrome, resulting in life-threatening neurological injuries.

CASE SUMMARY

A 20-year-old Chinese man with massive hemoptysis developed symptomatic hyponatremia (116 mmol/L) after therapy by a continuous intravenous drip of pituitrin. To normalize his serum sodium, a hypertonic saline infusion was applied for 3 d, and the pituitrin administration was stopped concurrently. Then, an overly rapid increase in serum sodium level (18 mmol/L in 24 h) was detected after treatment. One day later, the patient experienced a sudden onset of generalized tonic-clonic seizures, as well as subsequent dysarthria and dystonia. Magnetic resonance imaging revealed increased signal intensity in the bilateral symmetric basal ganglia on the T2-weighted images, compatible with a diagnosis of extrapontine myelinolysis. The patient received an intravenous administration of high-dose corticosteroids, rehabilitation, and neurotrophic therapy. Finally, his clinical abnormalities were vastly improved, and he was discharged with few residual symptoms.

CONCLUSION

Physicians should be fully aware that pituitrin can cause profound hyponatremia and its correction must be performed at a controlled rate to prevent the development of osmotic demyelination syndrome.

Desmopressin-Induced Severe Hyponatremia with Central Pontine Myelinolysis: A Case Report

Desmopressin, a synthetic vasopressin analog, is used to treat central diabetes insipidus, hemostatic disorders such as von Willebrand’s disease, and nocturnal enuresis. We present the case of a 69-year-old man who developed severe hyponatremia during treatment with intranasal desmopressin at 10 µg twice daily for chronic polyuria and nocturia thought to be due to central diabetes insipidus. After 5 months of therapy, the patient noticed progressive fatigue, anorexia, dizziness, weakness, light-headedness, decreased concentration, and new-onset falls. At 6 months of therapy, the patient was brought to the emergency department for altered mental status and was found to be severely hyponatremic with a serum sodium level of 96 mmol/L, down from a value of 134 mmol/L at the initiation of therapy. The intranasal desmopressin was discontinued and the patient was admitted to the intensive care unit where the hyponatremia was slowly corrected over the next week to 132 mmol/L, never increasing by more than 8 mmol/L a day, with careful fluid management. This included infusion of over 11 L of 5% dextrose to account for a high urine output, which peaked at 7.4 L in 1 day. However, while the recommended rate for sodium correction was followed, the patient’s magnetic resonance imaging of the brain obtained after discharge displayed evidence of central pontine myelinolysis. Despite this finding, the patient eventually returned to his baseline mental status with no permanent neurologic deficits.

Extrapontine myelinolysis associated with pituitrin: case report and literature review

Background

Hyponatremia is the most common electrolyte abnormality encountered in hospitalized patients, resulting from a varied spectrum of conditions. Both the primary disturbance and its correction can result in life-threatening neurological consequences. Extrapontine myelinolysis is one such complication that is associated with the rapid correction of hyponatremia. Here we describe a patient who developed extrapontine myelinolysis unexpectedly after the correction of hyponatremia, which involved the drug pituitrin.

Case presentation

A 24-year-old Chinese woman was transferred to our neurology department with the symptoms of dysarthria and quadriparesis developing one day after the correction of hyponatremia (from 118 mmol/L to 140 mmol/L), which followed with a continuous intravenous drip of pituitrin used to control hemoptysis in the emergency room. During the course, she developed involuntary movement. Magnetic resonance imaging changes were consistent with extrapontine myelinolysis.

Conclusion

This present case describes the mechanism of profound hyponatremia involving pituitrin, and the subsequent development of extrapontine myelinolysis. Physicians may approach effective clinical management of patients through awareness of the adverse effect of pituitrin on serum sodium levels, and avoid rapid correction of hyponatremia in clinical practice.

Desmopressin acetate (DDAVP)-associated hyponatremia and brain damage: a case series

BACKGROUND

Desmopressin (DDAVP) is typically prescribed for central diabetes insipidus, von Willebrands disease and for enuresis. DDAVP-associated hyponatremia is a known complication of DDAVP therapy. The currently recommended treatment for this condition calls for discontinuing DDAVP as part of the initial therapy. This recommendation could lead to a water diuresis and potentially over-correction of the serum sodium.

METHODS

The 15 patients in this case series developed symptomatic DDAVP-associated hyponatremia and were admitted to acute care hospitals. Thirty-eight percent presented with symptomatic hyponatremia and 62% developed symptomatic hyponatremia due to concomitant DDAVP and hypotonic intravenous fluid administration during a hospital stay. Group 1 patients (n = 13) were treated by withholding DDAVP and providing intravenous saline. Group 2 patients (n = 2) were treated by continuing DDAVP and providing DDAVP and intravenous hypertonic saline.

RESULTS

Among Group 1 patients, in whom DDAVP was withheld as initial management of DDAVP-associated hyponatremia (n = 13), the mean change in serum sodium in the first 2 days of treatment was 37.1 ± 8.1 mEq/L. The ultimate outcome in this group was death in 23%, severe brain damage in 69% and moderate brain damage in 8%. In Group 2 patients, in whom DDAVP was continued (n = 2) as part of the initial management strategy, the mean change in serum sodium was 11.0 ± 0 mEq/L in the first 2 days. The ultimate outcome was survival without neurological sequelae in both cases.

CONCLUSIONS

Discontinuing DDAVP in a patient with symptomatic DDAVP-associated hyponatremia can lead to rapid correction of the serum sodium and resultant severe neurological injury. In contrast, continuing the medication while correcting DDAVP-associated hyponatremia may lead to better outcomes by avoiding over-correction of the serum sodium. Thus, an alternative approach that we propose is to continue DDAVP as part of the initial management of this disorder.

Central pontine and extrapontine myelinolysis in children: a review of 76 patients

This study aimed to identify the causes and contributing factors, neurologic presentation, and outcomes of central pontine and extrapontine myelinolysis and to examine any trends in the presentation and course of these disorders over the past 50 years. Seventy-six pediatric cases were identified in the literature. Age, sex, decade of diagnosis, neurologic presentation, outcome, and attributed causes were extracted. The results showed that the diagnosis, course, and outcomes of central pontine and extrapontine myelinolysis clearly have changed over the past few decades. Early cases generally were diagnosed at autopsy as opposed to computed tomography or magnetic resonance imaging more recently. Ninety-four percent of cases prior to 1990 and only 7% of cases from 1990 onward resulted in patient mortality. The decade in which the case was reported was the strongest predictor of outcome (P < .001), followed by sodium dysregulation (P = .045) and dehydration (P = .07).

Clinical management of SIADH

Hyponatremia is the most frequent electrolyte disorder and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) accounts for approximately one-third of all cases. In the diagnosis of SIADH it is important to ascertain the euvolemic state of extracellular fluid volume, both clinically and by laboratory measurements. SIADH should be treated to cure symptoms. While this is undisputed in the presence of grave or advanced symptoms, the clinical role and the indications for treatment in the presence of mild to moderate symptoms are currently unclear. Therapeutic modalities include nonspecific measures and means (fluid restriction, hypertonic saline, urea, demeclocycline), with fluid restriction and hypertonic saline commonly used. Recently vasopressin receptor antagonists, called vaptans, have been introduced as specific and direct therapy of SIADH. Although clinical experience with vaptans is limited at this time, they appear advantageous to patients because there is no need for fluid restriction and the correction of hyponatremia can be achieved comfortably and within a short time. Vaptans also appear to be beneficial for physicians and staff because of their efficiency and reliability. The side effects are thirst, polydipsia and frequency of urination. In any therapy of chronic SIADH it is important to limit the daily increase of serum sodium to less than 8-10 mmol/liter because higher correction rates have been associated with osmotic demyelination. In the case of vaptan treatment, the first 24 h are critical for prevention of an overly rapid correction of hyponatremia and the serum sodium should be measured after 0, 6, 24 and 48 h of treatment. Discontinuation of any vaptan therapy for longer than 5 or 6 days should be monitored to prevent hyponatremic relapse. It may be necessary to taper the vaptan dose or restrict fluid intake or both.