Silent corticotroph adenoma: case report and literature review.

OBJECTIVE: To review the initial clinical manifestations and diagnosis of silent corticotroph adenoma. METHODS: We report a case and summarize the relevant literature. RESULTS: A 52-year-old patient with hypopituitarism underwent resection of a silent corticotroph adenoma. A circulating species was detected postoperatively, reactive in a highly sensitive adrenocorticotropic hormone (ACTH) 1-39 immunoradiometric assay (IRMA) and beta-endorphin or beta-lipotropin radioimmunoassay. The basal morning cortisol concentration consistently was <10 microg/dL. Dynamic testing was performed to screen for Addison's disease, congenital adrenal hyperplasia, and Cushing's syndrome. During dexamethasone suppression, the molar concentration of circulating ACTH precursors by a two-site IRMA was 55-fold greater than the concentration of ACTH 1-39 by IRMA. We concluded that the tumor displayed impaired processing of pro-opiomelanocortin (POMC) and secreted a bioinactive POMC-derived peptide that was reactive in the ACTH 1-39 IRMA. CONCLUSION: Patients with silent corticotroph adenoma do not have clinically evident Cushing's syndrome. In some cases, bioinactive ACTH precursors may be detected by a sensitive ACTH 1-39 IRMA.

Magnetic resonance imaging and pathological analysis of a pituicytoma: case report.

A case of a pituicytoma is presented that describes the clinical, pathological, and magnetic resonance imaging features of a rare tumor of the neurohypophysis. A 26-year-old woman presented with a 4-month history of dizziness and visual obscuration. A magnetic resonance image revealed a pituitary mass with suprasellar extension. The specimen obtained from a transsphenoidal decompression identified the mass as an astrocytoma of the posterior pituitary (pituicytoma). Immunohistochemical staining was positive for glial fibrillary acidic protein, S-100, and vimentin. Electron microscopy identified intermediate filaments, numerous broad cell junctions, no secretory granules, and two cellular populations with either an electron-dense or lucent cytoplasmic matrix. This case is unique in that other documented cases originating in the posterior pituitary have all been pilocytic astrocytomas, whereas this neoplasm was not a pilocytic variant. This is also the first case in the literature of a pituicytoma documented by magnetic resonance imaging. This report reviews the cytological elements of the neurohypophysis and the origin of pituicytomas and stresses the proper use of the term "pituicytoma" in relation to tumors of the posterior pituitary.

Recurrent intracranial epithelioid hemangioendothelioma associated with multicentric disease of liver and heart: case report.

Epithelioid hemangioendothelioma is an unusual vascular neoplasm with prominent cytoplasmic vacuolization representing primitive lumen formation. A case is presented of this unique vascular neoplasm in a woman with a seizure disorder who had cardiac, hepatic, and recurrent nervous system lesions. To our knowledge, this is the third known case of intracranial epithelioid hemangioendothelioma. Emphasis is placed on the indolent course of this rare neoplasm, with a recommendation for aggressive surgical treatment and diligent follow-up.

Adenocarcinoma metastatic to a growth-hormone-secreting pituitary adenoma: case report.

Although the pituitary gland is known to harbor metastatic deposits, it is a rare occurrence for a metastatic deposit to appear in a pituitary adenoma. A case is presented of an adenocarcinoma metastatic in an acromegalic patient with a pituitary adenoma. This report adds to the literature of the unusual phenomenon of neoplasm-to-neoplasm metastasis.

Severe cerebral damage in ornithine transcarbamylase deficiency.

Two patients are described with hyperammonemia due to ornithine transcarbamylase (OTC) deficiency who suffered severe shrinkage and collapse of the brain. The cerebral cortex was spongy and cavitated, containing only a few residual neurons, and was markedly gliosed. In one patient the basal ganglia were affected and harbored Alzheimer type II astrocytes. These lesions resemble those of acquired hepatocerebral degeneration and occur especially in female children with the milder form of the disease, who have a potential to survive. Strict observance of dietary restrictions is mandatory to avoid catastrophic damage to the brain.

Cortical biopsy results in Alzheimer's disease: correlation with cognitive deficits.

Neuropsychologic and pathologic data are presented for a group of 11 patients with a clinical diagnosis of probable Alzheimer's disease (AD) according to recently proposed criteria. In all cases, the diagnosis was verified by cortical biopsy. In addition, increased cortical plaque counts were associated with greater deficits in language production and comprehension and poorer performance on an index of global mental status. These results suggest that a clinical diagnosis of AD is very accurate when patient selection is restricted to typical cases and that language deficits may provide a useful indicator of severity of disease in AD patients.

Dual energy computerized tomography: a simplified approach.

Attenuation numbers of various organic liquids were measured in a phantom at the low and high X-ray beam settings of the Mark I and CT 1010. The readings were translated into absolute units and ratios computed. There is a nonlinear relationship between this ratio and the effective atomic number of the compounds tested. A ratio of one defines a substance with energy dependence like water. Ratios below one definite anhydrous substances composed of elements with low atomic numbers. Ratios greater than one defined substances containing elements with high atomic numbers.

Protein and electrolyte changes in experimental cerebral edema.

Analysis of protein and electrolyte data in cryogenic cerebral edema in the rhesus monkey has led to the conclusion that, in the first 24 hours (h) after injury, the edematous process is not homogenous, but compartmentalized. This involves, first of all, a division into intra- and extracellular compartments. The intracellular compartment is further divided into a compartment containing water, electrolytes, and serum proteins, and a compartment containing only excess sodium. The extracellular compartment is also subdivided into a compartment containing albumin, globulin, and electrolytes, and a compartment containing only albumin and electrolytes. Anatomically, the latter is most likely the pre-existing normal extracellular space.

A correlative study of computed tomography and histology in human and experimental vasogenic cerebral edema.

The computed tomography (CT) scans of nine patients with vasogenic cerebral edema and five monkeys with cryogenic lesions were correlated with histologic findings. The areas of diminished density on the CT scan corresponded to foci of histologically recognizable edema. The attenuation number of the edematous tissue in the human varied from 18.0 to 28.8 Hounsfield units (HU: 1,000 scale) and in the monkey from 27.0 to 34.7 HU. There was a rough correlation between the extent of decrease in the attenuation number and the degree of staining of edematous tissue by the periodic acid-Schiff method. The decreased attenuation number of edematous tissue signifies dilution by edema fluid only when it is above 20 HU or represents a change of less than 12 HU. Lower numbers imply an additional process, possibly transformation of complex into neutral lipids. It is our belief that cerebral edema in the human can be quantitatively studied with the presently available CT scanners.

Massive doses of steroids in cryogenic cerebral injury and edema.

Cryogenic lesions were produced in the brains of rhesus monkeys and the accompanying edema measured by quantitative chemical methods. No effect on this type of edema could be demonstrated in animals treated with massive doses of steroids.

Experimental acute lead encephalopathy in the juvenile rhesus monkey.

Lead subacetate (0.5g) and 1000 units of vitamin D were given three times a week to four newly-weaned rhesus monkeys. In addition, two animals received only the vitamin D. The poisoned animals had an increase in the urinary excretion of delta-aminolevulinic acid, an elevated content of lead in the blood, and a fall in hemoglobin concentration. Between 6 and 18 weeks the animals suddenly developed ataxia, nystagmus, generalized weakness, and convulsions. At this time the animals were killed by perfusion of fixative and the brain prepared for light and electron microscopic studies. Definite morphological evidence of disease was confined to the central nervous system, except for one animal which showed the characteristic renal inclusions of lead poisoning. All animals showed PAS-positive globules associated with blood vessels and an exudative edema involving the white matter of the cerebral hemispheres and cerebellum. Ultra-structurally, this appeared as a granular precipitate within an expanded extracellular space. Alterations of nerve fibers were not seen in the white matter but axonal swelling was observed in the cerebral cortex. The perikaryon and neuropil appeared normal. The control animals showed no significant cerebral changes.