Children with the
opsoclonus-myoclonus syndrome (OMS) usually respond to
corticotropin (
adrenocorticotrophic hormone,
ACTH) treatment but the mechanism of benefit is unknown. We previously showed that both cerebrospinal fluid (CSF)
homovanillic acid (HVA) and 5-hydroxyindole-acetic
acid (5-HIAA) concentrations are low in pediatric OMS. In this study, we measured levels of CSF
Dopa,
catecholamines, deaminated metabolites of
catecholamines, as well as HVA and
5-HIAA in eight patients before and during treatment with
ACTH. All the children were
ACTH-responsive with 50-70% improvement in multiple clinical features of OMS.
ACTH treatment reduced the HVA concentration in every child by a mean of 21% (p < 0.001). Treatment with
ACTH was associated with significant correlations between dopaminergic markers such as HVA, dihydroxyphenylacetic
acid (
DOPAC), and
Dopa. There were no significant changes in the CSF concentrations of the noradrenergic markers
norepinephrine (NE) and dihydroxyphenylglycol (
DHPG), or the serotonergic marker
5-HIAA. The only child with a marked inflammatory pattern in CSF, which was reversed by
ACTH, was atypical for a large increase in NE and decrease in
5-HIAA during
ACTH treatment. Beneficial effects of
ACTH in OMS are not associated with normalization of HVA or
5-HIAA levels. The pattern of decreased HVA and unchanged
DOPAC levels could reflect decreased extraneuronal uptake of
catecholamines (which
steroids inhibit) or decreased 0-methylation of
catecholamines in nonneuronal cells.