The spongy state: A form due to the agonal or postmortem evolution of gaseous carbon dioxide from glycogen

Dialysis encephalopathy: neuropathologic aspects

The clinical, epidemiologic, electroencephalographic, and toxicologic features of dialysis encephalopathy (DE) have been clarified, but the neuropathologic and clinicopathologic aspects of the disease have remained obscure. In three cases of DE associated with a dialysate of high aluminum content, spongy change restricted to the upper layers of the cerebral cortex was found. The spongy change was distributed through the cerebral cortex bilaterally and diffusely, but the left hemisphere was involved more severely and extensively than the right hemisphere, and the opercular portions of the frontal and temporal lobes were affected more than the remainder of those lobes. This topographic distribution correlated with the clinical defects in higher cortical functions, including aphasia. The spongy change consisted of vacuoles in the neuropil and inside nerve cell bodies. The vacuoles in the neuropil were located in dendrites, astrocytic processes, and, possibly, other structures. Thus, DE is a disease of neurons and astrocytes of the cerebral cortex. Although spongy change of the upper layers of the cerebral cortex is a nonspecific abnormality, when it occurs in the distribution described and in the absence of other diffuse cerebral diseases, it is characteristic of DE.

Creutzfeld-Jakob disease: clinical, EEG and neuropathological findings in a cluster of eleven patients

10 of 11 Creutzfeld-Jakob disease patients were seen between February 1975 and November 1979. Whilst the clinical and EEG findings were uniform, the neuropathological changes were not: astrogliosis was always diffuse and widespread but the other typical changes (neuronal loss and spongiosis) varied greatly both in degree and location.

[Hereditary spongiform dystrophy in young children (Canavan: van Bogaert-Bertrand)]

Hereditary spongiform dystrophy in young children is characterised by macrocephaly with spasticity, convulsions and ultimately a decerebrate state and diffuse electroencephalographic changes. Histological examination of the brain remains essential for its diagnosis. A review of the ultrastructural studies reported by various authors complements the findings obtained by conventional histology. We have thus endeavoured to determine whether van Bogaert-Bertrand's disease is to be considered as congenital or acquired. The anatomical findings in 3 cases together with the descriptions of other authors lead us to the following conclusions: -that the spongiform changes may be due to an osmolar disequilibrium in which the ATPase-Na/K relation with mitochondrial abnormalities is yet unclear. -that the constant finding of Alzheimer type II cells is certainly an indication of intra-astrocytic malfunction. -that the oedema blocks both myelin synthesis and its coiling into lamellae. Case 1, which showed a long survival compared to others described (about 4 years), enabled us to study terminal lesions. Sub-cortical zones, in both cerebrum and cerebellum, contained neither myelin nor spongiform cavities, but, on the other hand, showed a compact glio-fibrillosis with large vesicles and oligodendroglia of increased density. We have interpreted these lesions, progressively replaced by spongiosis deeper in the cortex, as evidence of retracted scar tissue. Differences found between cerebral weights seem to confirm this hypothesis.