Markedly elevated nitrate/nitrite levels in the cerebrospinal fluid of children with progressive encephalopathy with edema, hypsarrhythmia, and optic atrophy (PEHO syndrome).

PURPOSE: To compare the levels of brain nitric oxide production in patients with PEHO or PEHO-like syndrome and in controls with other neurologic disease.
METHODS: Nitric oxide metabolites, nitrates, and nitrites (NNx), were measured in the cerebrospinal fluid (CSF) of children with PEHO syndrome or PEHO-like syndrome, and in controls with other neurologic diseases.
RESULTS: The NNx levels were markedly higher in both PEHO (mean, 48 microM; p < 0.001) and PEHO-like (22 microM; p < 0.003) patients as compared with the controls (6 microM), but did not correlate with age or with brain atrophy or CSF levels of insulin-like growth factor-1 (IGF-1).
CONCLUSIONS: Our findings suggest that in PEHO syndrome, production of nitric oxide is markedly increased, suggesting that nitric oxide is involved in the pathologic phenomena (i.e., seizures and neurodegeneration) of the disease.