Hereditary Hyperammonæmia

Variants of citrullinaemia.

“…The degree of damage was related to the duration and height of the plasma ammonia level, and to the age of the patient. Raised ammonia levels seem to be more harmful in early infancy than later, as judged by histology (Bruton et al, 1970;Hopkins et al, 1969). Our patient with argininosuccinase deficiency (Baumgartner et al, 1968) confirms this view: this child died on the ninth day of life, and he too showed nerve cell and myelin degeneration and a microcystic lesion of the white matter.…”

“…Enlarged glial cells with intracellular lipoid accumulation were seen in Case 2. Few descriptions of pathological findings in enzymopathies of the urea cycle have been published (Vidailhet et al, 1971;Bruton, Corsellis, and Russell, 1970;Baumgartner et al, 1968;Hopkins et al, 1969). In some cases of omithine carbamylphosphate transferase deficiency both nerve cells and glial cells were affected, these patients having died between 7 months and 8 years of age.…”

Neuropathological Observations in a Patient with Carbamylphosphate-synthetase Deficiency and in Two Sibs

“…Cavanagh and Kyu (1971) demonstrated in rats with experimental portocaval shunts that the degree of Alzheimer type II astrocytic changes shows a direct positive correlation with the blood ammonia level. In their Case 1, however, Bruton et al (1970) in addition, described other, very severe, lesions which correspond closely to those observed in Case 1. Conclusion In all 3 sibs, severe brain damage was present.…”

“…Conclusion In all 3 sibs, severe brain damage was present. In one of two cases with a closely related inborn error, Bruton et al (1970) showed comparable brain damage.…”

“…Freeman et al (1970) very briefly state that in their patient with CPS deficiency and the sib who died after a similar illness, no significant abnormalities were found in the brain. Bruton, Corsellis, and Russell (1970) published neuropathological data of 2 patients with ornithine transcarbamylase deficiency that are of obvious interest, as the metabolic derangement resulting from this deficiency can be assumed to be very similar to that in CPS deficiency. In both patients they found marked 5 Alzheimer type II changes in astrocytes, such as are observed in many conditions in which blood ammonia levels are raised.…”