Síndrome diencefàlico: una causa poco común de malnutrición

Diencephalic Syndrome: A Rare Entity with Its Anaesthetic Management and Post-operative Complications of Diabetes Insipidus and Thrombocytopenia

Russell first described the diencephalic syndrome in 1951. It is a rare syndrome and usually presents in children as a cause of failure to thrive despite normal, or even increased appetite, with preservation of linear growth. The treatment options vary from endoscopic biopsy followed by chemotherapy to definitive surgical resection of the tumour. The authors here describe a case of an 8-year-old 10 kg emaciated child who presented with headache, vomiting, rage attacks, decreased weight, and diminution in vision. The child had bilateral optic atrophy; however, hormonal profiles were within normal limits. MRI of the brain gave an impression of craniopharyngioma.

Diencephalic syndrome: an anaesthetic challenge

Diencephalic syndrome is one of the rare causes of failure to thrive in infants and young children. It is caused by a tumour in diencephalon (thalamus and hypothalamus), characterised by profound emaciation with uniform loss of body weight despite normal or slightly decreased appetite, locomotor hyperactivity, euphoria and visual symptoms. Anaesthetic considerations due to decreased body fat include positioning to avoid pressure necrosis, measures to avoid hypothermia, proper drug dosing, treating electrolyte imbalances and delayed recovery. We report successful anaesthetic management of a child with diencephalic syndrome scheduled for an endoscopic biopsy of suprasellar space occupying lesion under general anaesthesia.

The role of leptin in diencephalic syndrome

Diencephalic syndrome is a rare condition associated with central nervous system tumors. The most common presentation is secondary failure to thrive with proper caloric intake and no statural impairment. Despite the importance of this syndrome, little is known of its pathophysiology. Some reports have documented changes in human growth hormone and insulin levels at the onset, whereas others have described endocrine disorders of hypothalamic insufficiency resulting from surgery of the tumor. It has been suggested that the hormonal changes described, such as increased human growth hormone and ghrelin or decreased insulin and leptin levels, are related to a patient's BMI. These findings support the role of these 4 hormones as indicators of the patient's nutritional status but not as mediators or potential therapeutic targets of the disease. We report the case of an infant who initially presented with tumor progression and, after chemotherapy, progressive weight gain and reduced tumor size. Because he presented no hormonal deficiencies or obesity after therapy, we were able to analyze his hormonal status uninfluenced by effects of metabolic treatment or excess weight. Although ghrelin and leptin levels have been related to nutritional status, our patient's leptin levels fell when tumor size decreased and weight increased: an extraordinary finding because leptin concentration is expected to increase with weight gain. This paradoxical response suggests that leptin may be dysregulated in diencephalic syndrome or that the diencephalic astrocytoma may have had an effect on leptin secretion.

Astrocitoma de vías ópticas: una causa infrecuente de retraso ponderal en el lactante

Failure to thrive is a frequent cause of consultation in pediatric services. The main objective in these patients is the early detection of an organic cause, if present. We report a case of low-grade astrocytoma of the optic pathway in a 2-month-old child whose main symptoms at diagnosis were failure to thrive and anorexia. Unfortunately, despite therapeutic efforts, the tumor showed local and metastatic progression refractory to chemotherapy. The patient died 3 months after diagnosis. We conclude that diencephalic tumors must be considered in the differential diagnosis of failure to thrive during the first year of life, especially when, after initial investigations, a cause is not found.