Thirteen children with progressive neuronal degeneration and liver disease are reported. Clinical features included developmental delay after a normal initial period with later onset of intractable epilepsy. The EEG showed an unusual but characteristic pattern, and visual evoked responses (VER) were abnormal. Rapidly progressive cerebral atrophy was seen on computerized axial tomography (CAT). Inheritance was consistent with an autosomal recessive trait. Pathological findings were neuronal degeneration and spongy change of the cerebral cortex. The calcarine cortex was more severely affected than other areas. Hepatic lesions included severe fatty change and cirrhosis. In six patients liver disease was detected before the onset of epilepsy and exposure to anticonvulsants. Two others were reported to have died from sodium valproate (SV) toxicity, but both had abnormal liver enzymes before treatment with SV, and in both the neuropathological findings were indicative of PNDC. During life, PNDC may be indicated by the characteristic clinical course, abnormal liver function tests, and abnormalities of EEG, VER, and CAT.

A clinicopathological study of 10 cases of progressive neuronal degeneration of childhood is reported. In the typical clinical course early developmental delay is followed by intractable epilepsy leading rapidly to death, in some cases in liver failure. Diagnostically useful investigations include characteristic EEG changes, evidence of progressive atrophy (particularly occipital) on CT scan, absent or reduced visual evoked responses, and biochemical evidence of abnormal liver function in many cases before commencement of anticonvulsant therapy. Siblings of 4 of the reported cases suffered a similar clinical disorder. Macroscopic appearances of the brain varied from virtual normality to severe atrophy. The cortical ribbon showed patchy lesions, but the calcarine cortex was characteristically involved, narrowed, granular and discoloured. Histological damage to the cerebral cortex was widespread but patchily accentuated. In milder lesions status spongiosus, astrocytosis and neuronal loss occurred only in the superficial cortex, in moderately affected areas deeper laminae were involved, and in the most severe lesions the entire cortex was reduced to a thin densely gliotic remnant. There was a pronounced tendency for the striate cortex to be the worst affected area. Of subcortical structures the thalamus, hippocampus and cerebellum were particularly severely involved. There was usually accompanying liver disease, particularly a subacute hepatitis comprising massive fatty degeneration, hepatocyte loss, bile duct proliferation and fibrous scarring, with or without cirrhosis. These pathological features are distinct from other combined degenerations of liver and brain and the cortical lesions differ significantly from the neuropathological sequelae of birth injury or severe epilepsy. Hepatic pathology is distinctive and does not appear to be related to drug therapy. It is concluded that these 10 cases of progressive neuronal degeneration of childhood with concomitant liver disease, together with a small number of previously reported cases, are a nosological entity which may result from an autosomal recessive inherited metabolic defect, the nature of which is at present obscure.

A clinico-pathological entity of progressive neuronal degeneration of childhood with liver disease has now been recognised. Onset is in early childhood with intractable fits and progressive dementia. EEG/ERG/VEP studies have been carried out in 12 children with this condition. In most patients the EEG showed strikingly similar and unusual abnormal patterns (high amplitude slow activity together with smaller polyspikes). The flash VEP was usually abnormal and often asymmetrical. In the appropriate clinical setting the neurophysiological features are sufficiently characteristic to aid the clinician in early diagnosis of this autosomal recessive disorder.

Mendelian inheritance involves the transmission to successive generations of DNA contained in genes in the nucleus, but DNA is also contained in mitochondria, where it is believed to be responsible for the encoding of certain mitochondrial enzymes. Since nearly all mitochondrial DNA is maternally transmitted, one might expect a nonmendelian pattern of inheritance in mitochondrial cytopathy, a syndrome in which there are abnormalities in mitochondrial structure and deficiencies in a variety of mitochondrial enzymes. We studied the pedigrees of 6 affected families whose members we had examined personally and of 24 families described in the literature. In 27 families, exclusively maternal transmission occurred; in 3 there was also paternal transmission in one generation. Altogether, 51 mothers but only 3 fathers had transmitted the condition. These results are consistent with mitochondrial transmission of mitochondrial cytopathy; the inheritance and enzyme defects of mitochondrial cytopathy can be considered in the light of recent evidence that subunits of respiratory-enzyme complexes are encoded solely by mitochondrial DNA. The occasional paternal transmission may be explained if certain enzyme subunits that are encoded by nuclear DNA are affected.

Three children, two siblings and one unrelated child, with congenital muscular dystrophy with central nervous system (CNS) involvement are discussed. The siblings appeared to suffer from a relatively mild myopathy with progressive brain disease, of which brain biopsy in one showed astrocytic proliferation in the white matter. In the patient with severe muscle disease, autopsy showed widespread patchy demyelination in the white matter and developmental abnormalities in the cerebral and cerebellar cortex. These patients differ from the Japanese (Fukuyama) cases of CMD in the severity of the changes in the cerebral white matter, and from Santavuori's cases in the absence of ocular abnormalities and hydrocephalus. Their unique nosology is discussed.

Two siblings are described with clinical features of the Joubert-Boltshauser syndrome. Both had polydactyly and one had fleshy tumours of the tongue. Computed tomography of the brain showed hypoplasia of the cerebellar vermis, associated in one case with a cyst of the fourth ventricle.

51-2 + 1*4 ILm3, which was also significantly less (p < 0.001) than that of 69-1 + 1-3 ,um3 measured in the controls.Reductions in nerve cell number and nuc- leolar volume of 67% and 26% respec- tively, are similar to these decreases in Alzheimer type dementia and Down's syn- drome and may be presumed, therefore, to lead to substantial depletion of brain noradrenaline in this condition also.It therefore seems that loss of noradrenergic activity is found in all those dementias charactensed by a neurofibril- lary degeneration of nerve cells even though senile plaques may not always be present.The alterations in protein synth- esis that lead to formation of paired helical filaments have been related to the presence of toxic substances, particularly aluminium,9 within the brain, which may accumulate from an altered permeability of the microvasculature, stemming from loss of modulation by noradrenergic fibres'0.Changes in cholinergic activity, similar to those in Alzheimer type dementia," and Down's syndrome,'2 occur in scrapie,' a slow virus disease affecting sheep and goats, in which amyloid plaques, similar to senile plaques, but not neurofibrillary changes, are present in the brain.'4This suggests that alterations in the cholinergic rather than noradrenergic neurotransmit- ter system may be fundamental to plaque formation in ATD and Down's syndrome, a conclusion strengthened by the close quantitative relationship'5 that occurs bet- ween reductions in choline acetyl transferase activity and frequency of senile plaques in cases of Alzheimer type dementia.