Diencephalic syndrome due to astrocytoma in three infants with failure to thrive

Abstract

Diencephalic syndrome (DS) is a group of conditions characterized by major features (severe emaciation despite normal or slightly decreased caloric intake, locomotor hyperactivity and euphoria) and minor features (skin pallor without anemia, hypoglycemia and hypotension). 1 Most of the reported cases showed clinical symptoms before the age of 2 years. An early sign of nystagmus leads to early recognition of this condition.We report three infants with poor oral intake, failure to thrive and nystagmus who were diagnosed with DS due to astrocytoma. The major point of this report emphasizes the recommendation that brain tumor should be thought to be a cause of unexplained failure of physical growth in infants. Patient 1 A 1-year-old female infant with failure to gain weight since the age of 7 months was brought to our hospital due to a need for another opinion. At 6 months of age, she developed poor oral intake and vomiting while being provided with a cow’s milkbased infant formula. Diagnosis of cow’s milk protein allergy (CMPA) was made by a primary physician.Although such cow’s milk-based infant formula was eliminated and an extensively hydrolyzed casein formula (EHF) was introduced, she still consumed little volume and vomited. On detailed history taking, the presence of involuntary rapid eye movement for 5 months led to suspicion of brain tumor; then nystagmus and atrophy of the left optic disc were detected. Her growth parameters are shown in Table 1. Investigations for panhypopituitarism and tumor markers were negative. Cranial computerized tomography (CT) revealed an illdefined non-enhancing hypodense lesion at the suprasellar region measuring 3.8 ¥ 3.8 cm in diameter with the absence of calcification. Subsequently, magnetic resonance imaging (MRI) of the brain revealed a well-defined, lobulated mass at the suprasellar region, involving the optic nerve, optic chiasm and hypothalamus with neither calcification nor a cystic component (Fig. 1). A spinal MRI demonstrated spinal metastasis at multi-levels of the cervical-thoracic-lumbar vertebra to the conus medullaris. Tumor biopsy was performed and the pathological report showed pilomyxoid astrocytoma (World Health Organization (WHO) grade II). Subtotal tumor removal was then performed. Enteral feeding with a medical formula had been provided via a nasogastric tube in combination with parenteral nutrition since admission. Chemotherapy consisting of vincristine and carboplatin was administered. After the operation, panhypopituitarism developed and was subsequently treated. Unfortunately, blindness also occurred. Appetite gradually increased and she could eat orally, so enteral feeding and parenteral nutrition were ceased. Five months later, her weight and length gain were 1720 g and 2 cm, respectively. After 11 months of treatment, cranial and spinal MRI showed a decrease in size of the suprasellar mass and no detectable tumor seeding at the cerebrospinal fluid (CSF) pathway. Patient 2