Posterior pituitary hematoma in a case of posttraumatic diabetes insipidus. Case report

Diabetes Insipidus after Traumatic Brain Injury

Traumatic brain injury (TBI) is a significant cause of morbidity and mortality in many age groups. Neuroendocrine dysfunction has been recognized as a consequence of TBI and consists of both anterior and posterior pituitary insufficiency; water and electrolyte abnormalities (diabetes insipidus (DI) and the syndrome of inappropriate antidiuretic hormone secretion (SIADH)) are amongst the most challenging sequelae. The acute head trauma can lead (directly or indirectly) to dysfunction of the hypothalamic neurons secreting antidiuretic hormone (ADH) or of the posterior pituitary gland causing post-traumatic DI (PTDI). PTDI is usually diagnosed in the first days after the trauma presenting with hypotonic polyuria. Frequently, the poor general status of most patients prevents adequate fluid intake to compensate the losses and severe dehydration and hypernatremia occur. Management consists of careful monitoring of fluid balance and hormonal replacement. PTDI is associated with high mortality, particularly when presenting very early following the injury. In many surviving patients, the PTDI is transient, lasting a few days to a few weeks and in a minority of cases, it is permanent requiring management similar to that offered to patients with non-traumatic central DI.

Lasting pituitary hormone deficiency after traumatic brain injury

Pituitary deficiencies have been reported after traumatic brain injury (TBI) and may contribute to lasting cognitive disorders in this context. In a population of TBI patients with persistent cognitive and/or behavioral disorders, we sought to determine the prevalence of lasting pituitary deficiency and relationships with TBI severity, cognitive disorders, and impairments in activities of daily living (ADL). Fifty-five patients were included (mean age 36.1 years; 46 men) at least 1 year after TBI. They underwent a comprehensive evaluation of pituitary function (basic tests and stimulation), initial TBI severity, and long-term outcomes (cognitive performance, Glasgow Outcome Scale score, impact on ADL, and quality of life [QoL]). We used chi-squared and Mann-Whitney tests to probe for significant (p≤0.05) relationships between pituitary disorders and other parameters. Thirty-eight (69%) patients had at least one pituitary hormone deficiency. Growth hormone deficiency was more prevalent (severe: 40.0%; partial: 23.6%) than corticotropin (27.3%) or thyrotropin (21.8%) deficiencies. Other deficiencies were rare. Growth hormone deficiency was associated with attention and verbal memory disorders and reduced involvement in ADL. We did not find any relationship between pituitary deficiency and the TBI's initial severity. In a multivariate analysis, the TBI severity was introduced as a first factor, and pituitary deficits as a secondary factor for explaining the late outcome (ADL and QoL). In conclusion, TBI patients with cognitive sequelae must undergo pituitary screening because growth hormone, corticotropin, and thyrotropin deficits are particularly common and can adversely affect ADL and reduce QoL.

Neuroendocrine function following traumatic brain injury and subsequent intensive care treatment: a prospective longitudinal evaluation

Neuroendocrine dysfunction following traumatic brain injury (TBI) has been described extensively. However, few studies are longitudinal and most lack subtle radiological, clinical, and repetitive endocrine assessment in the acute phase. Accordingly, we prospectively assessed neuroendocrine function in 71 patients after TBI. Injury was documented by a computed tomography (CT). During the first week, critical clinical data (Glasgow Coma Score, APACHE score), treatment variables such as duration of analgosedation for mechanical ventilation, were related to basal pituitary function. More than 2 years later, a subgroup of patients was re-evaluated using dynamic testing with ACTH and GHRH-arginine tests. The Pearson's correlation analysis and Mann-Whitney rank sum test for group differences were used for statistical analysis. None of the CT findings predicted neuroendocrine dysfunction following TBI. The adaptive response to critical illness with significantly elevated cortisol levels on admission and decreased levels thereafter in patients ventilated for more than 24 h (p < 0.05) was attenuated following severe TBI (p < 0.05). However, the coincidence of low serum cortisol and increased urinary excretion of glucocorticoid metabolites in about 80% of patients challenges the relevance of basal hormone measurements. In ventilated patients, total T3 and free T4 were decreased (p < 0.05), TSH was low on day 3 (p < 0.05), and a gonadotropic insufficiency was present (p < 0.05). The thyrotropic and gonadotropic system recovered completely within the follow-up period. With regard to the somatotropic system, neither brain injury severity nor mechanical ventilation was associated with an insufficiency during the acute phase post-injury. However, initially low GH levels predicted a persistent deficiency (r = 0.731, p < 0.001). We conclude that both severe TBI and prolonged mechanical ventilation result in hormonal disturbances early after injury, suggesting a pathophysiological response to brain injury and subsequent intensive care treatment rather than morphological damage.

Disturbances of sodium in critically ill adult neurologic patients: a clinical review

Disorders of sodium and water balance are common in critically ill adult neurologic patients. Normal aspects of sodium and water regulation are reviewed. The etiology of possible causes of sodium disturbance is discussed in both the general inpatient and the neurologic populations. Areas of importance are highlighted with regard to the differential diagnosis of sodium disturbance in neurologic patients, and management strategies are discussed. Specific discussions of the etiology, diagnosis, and management of cerebral salt wasting syndrome, the syndrome of inappropriate antidiuretic hormone secretion, and central diabetes insipidus are presented, as well as the problems of overtreatment. The importance of diagnosis at an early stage of these diseases is stressed, with a recommendation for conservative management of milder cases.

External causes of metabolic disorders

Common medical conditions, such as head trauma, malignancy,and pregnancy may be associated with rarely seen metabolic emergencies that require prompt recognition and therapy. Although care of the primary disorder is the focus of initial management,identification of the associated endocrinopathy is important. These clinical syndromes, although uncommon, must be considered when evaluating patients, as prompt treatment may minimize the mortality and morbidity of these conditions.

Endocrine dysfunction following traumatic brain injury: mechanisms, pathophysiology and clinical correlations

Despite growing recognition among those who provide care for traumatic brain injury patients, endocrine dysfunction following brain injury is an often under-recognized phenomenon. From historical reports one would conclude that endocrine dysfunctions hardly ever occurs following trauma to the head. However, recent studies suggest that a significant proportion of patients suffer some degree of hypopituitarism. To date, there are no clear predicting factors identifying patients at risk for developing hormonal disturbances and thus no parameters exist for screening. Several retrospective analyses and literature reviews, and more recently, a few longitudinal studies of brain injured patients have been performed.

Bitemporal head crush injuries: clinical and radiological features of a distinctive type of head injury

OBJECT

Most craniocerebral injuries are caused by mechanisms of acceleration and/or deceleration. Traumatic injuries following progressive compression to the head are certainly unusual. The authors reviewed clinical and radiological features in a series of patients who had sustained a special type of cranial crush injury produced by the bilateral application of rather static forces to the temporal region. Their aim was to define the characteristic clinical features in this group of patients and to assess the mechanisms involved in the production of the cranial injuries and those of the associated cerebral and endocrine lesions found in this peculiar type of head injury.

METHODS

Clinical records of 11 patients were analyzed with regard to the state of consciousness, cranial nerve involvement, findings on neuroimaging studies, endocrine symptoms, and outcome. Furthermore, an experimental model of bitemporal crush injury was developed by compressing a dried skull with a carpenter's vice. Seven of the 11 patients were 16 years old or younger. All patients presented with a characteristic clinical picture consisting of no loss of consciousness (six patients), epistaxis (nine patients), otorrhagia (11 patients), peripheral paralysis of the sixth and/or seventh cranial nerves (10 patients), hearing loss (five patients), skull base fractures (11 patients), pneumocephalus (11 patients), and diabetes insipidus (seven patients). Ten patients survived the injury and most recovered neurological function.

CONCLUSIONS

Static forces applied to the head in a transverse axis produce fractures in the skull base that cross the midline structures without producing significant cerebral damage. Stretching of cranial nerves at the skull base explains the nearly universal finding of paralysis of these structures, whereas an increase in the vertical diameter of the skull accounts for the occurrence of diabetes insipidus in the presence of an intact function of the anterior pituitary lobe. The association of clinical, endocrine, and neuroimaging findings encountered in this peculiar type of head injury supports the idea that this subset of injured patients has a distinctive clinical condition, namely the syndrome of bitemporal crush injury to the head.

MRI in the differential diagnosis of a sellar mass

Whilst pituitary adenomas are the commonest cause of a sellar mass, there are a number of other neoplastic, infectious, inflammatory, developmental and vascular aetiologies that should be considered by the radiologist. We discuss and illustrate these lesions and indicate the various magnetic resonance imaging features that are helpful in formulating an appropriate differential diagnosis.

Anterior hypopituitarism with unusual delayed onset of diabetes insipidus after penetrating head injury

Neuroendocrine dysfunctions are among the various complications that occur after traumatic brain injury. We report a case of onset of diabetes insipidus during acute rehabilitation of a 20-yr-old patient with a traumatic brain injury caused by a gunshot wound. Our case is the latest onset of diabetes insipidus after traumatic brain injury that has been reported in the literature.

Pituitary insufficiency after penetrating injury to the sella turcica

We report a 28-year-old male patient with a pituitary insufficiency after a simple fracture of the sella turcica. He was injured by a long nail that punctured the lower jaw. No fracture other than that of the sella turcica was detected. An endocrinological examination revealed both anterior and pituitary dysfunction and diabetes insipidus that continued for about two months.