Abnormal carbohydrate metabolism in cerebrospinal fluid in Rett syndrome.

We analyzed lactate, pyruvate, and citric acid cycle intermediates in cerebrospinal fluid by high-performance liquid chromatography in Rett syndrome patients (n = 27; mean age, 5.7 +/- 3.4 years) and age-matched female controls (n = 12; mean age, 7.0 +/- 3.3 years). The lactate, pyruvate, alpha-ketoglutarate, and malate were significantly elevated in Rett syndrome compared to the controls. The lactate/pyruvate ratio was not different. On the other hand, cerebrospinal fluid citrate, cis-aconitate, succinate, fumarate, and oxaloacetate were not significantly different in Rett syndrome patients than in the controls. We also evaluated the correlation between these acids and clinical symptoms and signs, including clinical stage, seizures medications (anticonvulsants or naltrexone), developmental quotient, self-abuse, and hyperventilation or apnea or both. The concentrations of all these acids did not differ significantly with clinical stage. Lactate elevation significantly correlated with apnea. Lactate and pyruvate elevation significantly correlated with hyperventilation or with both breathing abnormalities. Our observations in this sample of patients with Rett syndrome led us to speculate that patients with the Rett syndrome may have defective carbohydrate metabolism. Elevated mitochondrial reduced nicotinamide-adenine dinucleotide-linked substrates suggest that reduced nicotinamide-adenine dinucleotide-ubiquinone oxidoreductase may be deficient in the brain in Rett syndrome patients.

Long-term observation of the changing brainstem auditory evoked potentials in a case of infantile opsoclonus-polymyoclonia syndrome.

Brainstem auditory evoked potential (BAEP) studies were repeatedly carried out on a boy with infantile opsoclonus-polymyoclonia syndrome, from 15 months to 39 months of age, the following being revealed: the I-III interpeak latency (I-III IPL) was more or less in the upper normal range until 24 months and then remained at the same level throughout the rest of the observation period, not showing physiological shortening with maturation. It should be noted that the prolongation of I-III IPL continued in spite of the disappearance of the opsoclonus.

The Rett syndrome and CSF lactic acid patterns.

We investigated both blood and cerebrospinal fluid (CSF) lactate and pyruvate levels in seven girls with the Rett syndrome (RS) and evaluated the relationship between CSF lactate and pyruvate levels and the clinical manifestations, particularly seizures, anticonvulsant medication, and breathing dysfunction including breath holding, apnea and hyperventilation. Elevated lactate and pyruvate levels in CSF with normal serum lactate were found in two RS patients. Elevated CSF lactate correlated significantly with the clinical occurrence of hyperventilation (P0 = 0.048, Fisher exact probability). We measured native and dichloroacetate (DCA)-activated pyruvate dehydrogenase (PDH) complex activities in two patients (#1 and 2) using cultured lymphoblastoid cell lines which were transformed by EB virus and the results were normal. We also analyzed CSF citric acid intermediates from 7 RS patients including citric acid, cis-aconitate, alpha-ketoglutarate, succinate, fumarate, malate and oxaloacetate. These concentrations were not significantly different from those control patients (N = 21). An elevated lactate level may be a clue to clarify the etiology of RS.

MR imaging of birth brachial palsy in a two-month-old infant.

A female baby at two months old was diagnosed as having birth branchial palsy and was studied by magnetic resonance imaging (MRI) which is a non-invasive and safe method for assessing any brachial plexus injury in the infant. A traumatic meningocele involving a root avulsion injury was clearly demonstrated by the MRI findings.

Fragile X syndrome in Japanese patients with infantile autism.

Forty-seven patients (39 boys and 8 girls) with infantile autism whose clinical symptoms had matched the diagnostic criteria of DSM III were studied cytogenetically for the occurrence of fragile X [fra(X)] syndrome. The existence of fra(X) chromosome in these patients was screened first by culturing peripheral blood lymphocytes in a medium in which folic acid was absent; the fra(X) chromosome then was confirmed by reculturing in another medium to which 5-fluoro-2'-deoxyuridine was added for the last 24 hours of culture. Fra(X) chromosome was found in 2 of 39 male patients, but in none of the female patients; the 2 patients are siblings. Thus, fra(X) syndrome occurs in 2.6% (1/38) in this study population of male autistic children. The frequencies of fra(X) expression in the older brother with mild mental retardation, in the more severely retarded younger brother, and in their mother were 3-5%, 17-20%, and 9-3%, respectively. Of the two methods used in the present study, the method employing 5-fluoro-2'-deoxyuridine tended to be more sensitive to fra(X) chromosome detection, especially for a suspected carrier.