[Suprasellar arachnoid cyst associated with precocious puberty: report of an operated case and review of the literature].

The pathogenesis remains unknown in the majority of patients with precocious puberty, and yet infrequently such causative cerebral lesions as hypothalamic hamartomas are associated with sexual precocity. We reported a rare case of suprasellar arachnoid cyst in an infant presenting with precocious puberty, which eventually disappeared after a cyst-peritoneal shunt. It was believed that the mass effect of the arachnoid cyst upon the hypothalamus was, at least in part, responsible for development of precocious puberty. The role of surgical decompression of the cyst was also discussed. A one-year-old girl was admitted to the hospital for evaluation of genital bleeding which had persisted on and off for two months. The height, 80cm, and the weight, 12.4kg, exceeded by far the two standard deviations from the mean level of the normal population. In addition she had the development of breast tissue as classified Tanner's Stage II, and both pubic and axillary hair. The bone age by skeletal survey of the hand was rated as 3 years. Endocrinological examination showed that serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and estradiol had increased for her age, to levels equivalent to those for females at puberty. An LH-RH test revealed an excessive LH reaction. There were no definite neurological deficits. CT and MRI demonstrated the presence of a large arachnoid cyst involving the suprasellar region as well as the right middle and posterior fossa. After the patient underwent a cyst-peritoneal shunt, the cyst decreased in size and such symptoms as genital bleeding and breast growth disappeared. Serum levels of her LH and FSH also significantly decreased.(ABSTRACT TRUNCATED AT 250 WORDS)