Cv. Bellieni et al., EEG in assessing hydroxycobalamin therapy in neonatal methylmalonic aciduria with homocystinuria, BIOL NEONAT, 78(4), 2000, pp. 327-330
We performed serial electroencephalograms (EEG) in a newborn with methylmal
onic aciduria and homocystinuria to assess the effects of hydroxycobalamin
(OHcbl) therapy on the CNS. Diagnosis was made at 22 days of age: she had t
orpor, failure to thrive and hypotonia of the limbs, and intermittent opist
hotonus. The first EEG, performed on the first day of therapy, showed abnor
mal and immature transients, low voltage and very long flat periods in the
discontinuous part of the tracing. These features quickly improved during t
herapy. After 13 days of OHcbl therapy, the EEG tracing became normal for c
onceptional age and showed normal sleep phases with only minor anomalies; o
nly mild hypotonia still remained and biochemical parameters normalized. Th
e decrease in blood homocysteine (index of brood detoxification) was statis
tically correlated to the reduction of the length of flat periods in EEG (p
< 0.01). In conclusion, changes in neonatal EEG, particularly the length o
f interburst periods in the intermittent part of the tracing, appeared to b
e a reliable index for evaluating drug effectiveness in methylmalonic acidu
ria and homocystinuria. Copyright (C) 2000 S. Karger AG, Basel.