The syndrome of hypothalamic hypopituitarism complicating viral meningoencephalitis

Abstract

Diffuse hypothalamic-hypopituitarism complicating viral meningoencephalitis has been rarely documented. In this report, we describe the syndrome in a 41 yr old male and review the literature. Detailed endocrine studies were performed 1 month after the onset of apparent viral encephalitis. Repeated 08:00 h serum cortisol levels were low, but increased after administration of lysine-vasopressin. Urine 17-hydroxy-corticosteroid (17-OHCS) values rose with prolonged cortrosyn infusion, but failed to respond after administration of metyrapone. Serum thyroxine was decreased; basal levels of serum thyrotropin were low-normal, but there was a prolonged response to tyrotropin (TSH) to thyrotropin releasing hormone (TRH). Basal prolactin was elevated with a minimal response after TRH. Testosterone and gonadotropins were both diminished, and gonadotropins increased (but less than in normal subjects) after injection of gonadotropin releasing hormone (LHRH). The overnight water deprivation test confirmed the presence of diabetes insipidus. In the present context, the abnormal endocrine investigations were strongly supportive of disturbed hypothalamic activity. Hypothalamic-hypopituitarism following viral meningoencephalitis may occur more frequently than previously reported, and thus basal pituitary function should be assessed in all patients with viral meningoencephalitis.

Hypothalamic–pituitary insufficiency following infectious diseases of the central nervous system

“…A CT of the head revealed a contrast-enhanced suprasellar lesion in this particular patient (19). The endocrine deficiencies reached from complete panhypopituitarism including diabetes insipidus (14)(15)(16)18) to various partial defects (14,15,17). Data of these patients are given in Table 4.…”

“…In only one patient (15), imaging of the head had been performed during acute illness, revealing no abnormalities of the pituitary gland or hypothalamus. In earlier case reports, endocrine investigations and elevated basal PRL levels (probably due to the loss of tonic inhibition of the pituitary lactotrophs by the hypothalamus) were suggestive of a hypothalamic rather than a pituitary lesion (14,16,18). On the contrary, in other patients, the pituitary gland seemed directly affected (15,17).…”

“…Reports of anterior pituitary dysfunction following infectious diseases of the CNS are rare, and the incidence has not yet been studied systematically. In almost all reported cases, the anterior pituitary insufficiency was caused by viruses (14)(15)(16)(17)(18), and only one bacterial meningoencephalitis associated with diabetes insipidus and suspected corticotropic insufficiency has been reported. A CT of the head revealed a contrast-enhanced suprasellar lesion in this particular patient (19).…”

“…In most of the early case reports, the deficient hormone secretion has been caused by tuberculous meningitis (11)(12)(13). There are, however, reports to show that other infectious agents may also cause hypothalamic-pituitary dysfunction (14)(15)(16)(17)(18)(19). Therefore, the aim of the present investigation was to determine the incidence of hypothalamic-pituitary insufficiency in patients with previous infectious diseases of the CNS of different etiologies and mild-to-moderate clinical course.…”

The Effects of Meningitis on Anterior Pituitary Functions

“…Prospective-retrospective studies and isolated case reports have shown an incidence of increased pituitary insufficiency following CNS infections [1,[4][5][6][7][8][9][10]. However, these studies are not sufficient in number [5][6][7].…”