[The studies of melatonin values in the cerebrospinal fluid of hydrocephalic patients]

The changes in daytime levels of melatonin (MLT) in the cerebrospinal fluid (CSF) of twenty seven hydrocephalic patients were studied by the high-performance liquid chromatography (HPLC) method. Patients comprised three with congenital hydrocephalus (spina bifida 1, Chiari type II malformation 2), four post-meningitic hydrocephalus, fifteen brain tumors (chiasmal germinoma 3; malignant glioma of frontal 3, and temporal lobes 1; germinoma 1, teratoma 2, yolk sac tumor 1, epidermoid 1 in pineal region) and five cases of normal pressure hydrocephalus. CSF was collected between 0930 and 1030 h through puncture of the flushing device of shunt system or the lateral ventricle. The lowest value of MLT detected by HPLC was 15 pg/ml. Melatonin values were higher in patients aged under 10 years than over 20 years in the absence of meningitis or tumor in the pineal region. Even at ages over 15 years, higher CSF MLT values were obtained in the patients with meningitis or tumors in the pineal region. These results suggest that the inflammation or invasion of tumor into the pineal gland may stimulate the secretion of MLT by the pineal gland. However, lower MLT values were obtained in all patients over 40 years old. For these reasons, if one may use the changes of MLT values in CSF as a tumor marker or for determination of the treatment modality, time of CSF collection, age of patient, location or character of the tumor and presence of meningitis should be given due consideration. Also, the presence or absence of the rhythmical changes of melatonin values in a day following circadian rhythm are very important in determination of the treatment modality.