Diabetes insipidus secondary to penetrating thoracic trauma

Central diabetes insipidus after staged spinal surgery

Diabetes insipidus (DI) is described following penetrating spinal cord trauma but rarely following instrumented spinal fusion. More commonly, hyponatremia is seen following spine surgery, which may be iatrogenic, attributed to the syndrome of inappropriate antidiuretic hormone release. The authors present a case of a 57-year-old woman who underwent a planned two-stage operation for scoliotic deformity correction. On the third postoperative day, the patient developed hypernatremia (sodium levels of 157 mmol/L) and polyuria. In conjunction with endocrinology, the patient was diagnosed with central DI. The patient was treated with desmopressin acetate (DDAVP), which led to resolution of her symptoms. DDAVP was temporary and eventually weaned off. Central DI is a possible cause of hypernatremia following significant spine surgery. Correct diagnosis is paramount for rapid and appropriate treatment.

Differential Diagnosis of Polyuria and Polydipsia in a Patient with Spinal Cord Injury

We report the case of a 35-yr-old tetraplegic man who experienced increased water intake, constant thirst, and a copious amount of urine excretion after his spinal cord injury and in whom an intermittent catheterization program was unmanageable. Laboratory evaluation revealed low serum and urine osmolality, which were suggestive of psychogenic polydipsia, and hypokalemia, which might lead to polyuria with a compensatory polydipsia. His water intake was reduced with antidepressant therapy and potassium supplementation and normalized on the third month of the treatment. Physicians should be aware of the differential diagnosis of polyuria and polydipsia, which interfere with neurogenic bladder management in patients with spinal cord injury.

Idiopathic central diabetes insipidus is associated with abnormal blood supply to the posterior pituitary gland caused by vascular impairment of the inferior hypophyseal artery system

Central diabetes insipidus (CDI) has been linked to vascular central nervous system damage, although the pathophysiology of the mechanism has never been perfectly understood. Indeed, the vascular system of human pituitary gland has rarely been the subject of rigorous investigation except at postmortem. Recently, studies of pituitary gland blood supply have been carried out by means of a time evaluation of pituitary gland enhancement with noninvasive dynamic magnetic resonance (MR) imaging after contrast medium injection. In the present study, we decided to investigate the status of posterior pituitary blood supply by evaluating vascular pituitary patterns in a group of 19 patients with idiopathic CDI in whom previous standard MR imaging had failed to identify causal specific lesions. The control group was composed of 55 subjects with a median age of 12 yr (range, 4.2-17 yr) who had idiopathic isolated GH deficiency and normal pituitary morphology and 15 young adults (18-25 yr) who had normal pituitary gland and no endocrine dysfunction. Nineteen patients (12 females and seven males), ranging in age at the time of diagnosis of CDI from 0.5-14.9 yr (median, 5 yr), were examined with dynamic MR imaging between 1990 and 1997 at a median age of 14.1 yr (range, 5.0-26.3 yr). CDI was diagnosed according to clinical findings of polyuria and polydipsia, water deprivation test, and desmopressin acetate therapeutic trial. All of the patients had permanent CDI and were being treated with satisfactory results with desmopressin, two to three times daily, either intranasally or orally. The previous MR imaging findings of the 19 CDI patients had shown the absence of posterior pituitary hyperintensity, normal pituitary stalk, and normal anterior pituitary size. Enhancement of the straight sinus, representing a temporal reference point and occurring in normal subjects simultaneously to that of the posterior pituitary gland, was observed in all subjects after iv gadopentetate dimeglumine administration, with no substantial differences between patients and controls. However, the enhancement of the posterior pituitary lobe occurred simultaneously with the enhancement of the straight sinus in all of the controls but in only 14 of the 19 patients with CDI. In the remaining five patients, the enhancement of the straight sinus was not associated with the expected contrast enhancement of the posterior pituitary gland, suggesting abnormal blood supply to the posterior pituitary lobe. This is in keeping with vascular impairment of the inferior hypophyseal artery system and suggests that abnormal blood supply to the posterior pituitary gland is associated with what, until now, has been considered idiopathic CDI.

Diabetes insipidus secondary to penetrating spinal cord trauma: case report and literature review

STUDY DESIGN

Case report.

OBJECTIVE

To present a case of central diabetes insipidus (CDI) that developed after a gunshot injury to the thorax and thoracic spinal cord and to discuss the disease process in light of the relevant literature.

SUMMARY OF BACKGROUND DATA

Antidiuretic hormone (ADH) abnormalities may develop after spinal trauma and/or surgery. Although there are published reports of inappropriate ADH syndrome arising in this clinical picture, CDI is rare.

METHODS

A 33-year-old woman with hemopneumothorax and a gunshot wound to her thoracic spine was treated with chest tube drainage. No surgery was performed for the spinal injury. The patient was paraplegic on admission and rapidly developed excessive urine output. Testing revealed that her serum ADH level was low, consistent with CDI. Desmopressin acetate nasal spray was the prescribed treatment.

RESULTS

The patient responded well to the desmopressin acetate spray.

CONCLUSIONS

CDI is a complicated hormonal disorder characterized by excessive urine output. It is typically linked to an abnormality in the hypothalamohypophyseal axis that markedly reduces ADH production. The most common inciting causes are craniocerebral trauma, brain tumor and/or surgery, and central nervous system infection. Although uncommon, CDI should be considered when a spinal trauma patient develops excessive urine output.

Neurogenic diabetes insipidus in children with hypoxic encephalopathy: six new cases and a review of the literature

Hypoxic encephalopathy is rarely mentioned as a cause of neurogenic diabetes insipidus (DI) in children. We here report six cases of DI which occurred after severe hypoxic/ischaemic brain damage and include a review of the literature on 28 paediatric cases of neurogenic DI due solely to severe hypoxia/ischaemia. Airway obstruction, haemorrhagic shock and sudden infant death syndrome are the three major causes of hypoxia/ischaemia. The ages (25/28) ranged from 0.03 to 18 years (mean 7.27 years, median 5 years). The intervals between the hypoxic insult and the onset of DI (23/28) ranged from 0.08 days (2 h) to 13 days (mean 4.07 days, median 3.5 days). Linear regression analysis revealed no significant correlation between the age and the interval. Nineteen cases (82.6%) developed DI within 6 days after the hypoxic/ischaemic insult. Only two neonates survived with developmental delay. The remaining 26 cases died.

CONCLUSION

Neurogenic DI can be caused by hypoxia/ischaemia and is an ominous sign of severe brain damage in children with hypoxic encephalopathy. It is important to recognize this potential sequel by regularly monitoring intake and output, plasma sodium level, and urine specific gravity.