Cerebral white-matter changes suggesting leukodystrophy in ataxia telangiectasia.

Ataxia telangiectasia is an autosomal recessive disorder characterized by progressive cerebellar ataxia, recurrent sinopulmonary infections, oculocutaneous telangiectasia, selective immunoglobulin deficiency, and defective cellular immunity. We report a 4-year-old girl with ataxia telangiectasia whose initial magnetic resonance imaging (MRI) scan at 17 months of age showed leukoencephalopathy compatible with a leukodystrophy, a neuroimaging feature of ataxia telangiectasia that has not been described. Ataxia telangiectasia was not suspected until the child developed more typical clinical features. Diffuse white-matter high signal intensity on T2-weighted MRI scans may occur in the early stages of ataxia telangiectasia. This disease should be considered in the differential diagnosis of any child with a history and MRI findings suggestive of one of the leukodystrophies. The nonneurologic manifestations of ataxia telangiectasia may be of help diagnostically in this clinical setting.

Intravenous midazolam suppression of pentylenetetrazol-induced epileptogenic activity in a porcine model.

Generalized tonic-clonic seizures are a neurologic emergency. Duration of ictal activity has been associated with neurologic sequelae. The purpose of this study was to determine if midazolam, a short-acting benzodiazepine, could effectively ablate ictal activity in an animal model without significant cardiorespiratory compromise. Ten domestic swine (10 to 20 kg) were ventilated and hemodynamically monitored. Bifrontal craniotomies were performed and electrocortical activity was recorded throughout the experiment. Pentylenetetrazol (100 mg/kg) was administered iv to induce seizures. Midazolam (0.1 mg/kg) was administered iv and serum levels were drawn at 1, 2, 5, 10, 15, and 20 min after administration. There was no significant difference between the baseline and postmidazolam vital signs. Seizure activity was seen periodically as generalized spikes, as well as individual spikes for 29 +/- 5 sec after midazolam administration. A period of attenuation of 24 +/- 7 sec was seen before returning to baseline electrocortical activity. Our study demonstrates that midazolam effectively ablated induced ictal activity without significant cardiorespiratory depression and with similar EEG effect as other benzodiazepines.

Colpocephaly: frequency and associated findings.

Colpocephaly is an abnormal enlargement of the occipital horn of the lateral ventricle, also described as persistence of the fetal configuration of the lateral ventricles. Since it was first described, colpocephaly has been found in association with a number of abnormalities of the brain. In order to determine the frequency of this ventricular configuration at our hospital, we reviewed 3,411 computed tomographic (CT) scans done over a 26-month period. Fourteen cases were identified in which the CT scan had the appearance of colpocephaly. These CT scans were performed during the evaluation of a number of different clinical problems. Agenesis of the corpus callosum was the most frequently associated malformation. The types of malformations commonly associated with colpocephaly suggest that colpocephaly is merely a marker of disordered brain formation and that insults occurring anytime between one and four months of gestation may result in this anomaly.

Infantile botulism.

We present the first two known cases of infantile botulism in Oklahoma. The first case was due to type B toxin; the second was due to type A toxin. Both cases demonstrate most of the classic features of what now appears to be the most common form of botulism. Infantile botulism is an underrecognized but reversible cause of hypotonia. In most cases, the prognosis is excellent with institution of appropriate supportive care. The recognition of cranial nerve palsies or a history of constipation should raise the suspicion of infantile botulism. Aminoglycoside antibiotics and other agents that may precipitate or exacerbate neuromuscular blockade should be used with extreme caution in hypotonic infants until the cause of the hypotonia is clearly identified.

Benign extracerebral fluid collections: a cause of macrocrania in infancy.

In order to determine the frequency and natural history of benign extracerebral fluid collections, computed tomography reports from a period of 26 months at Oklahoma Children's Memorial Hospital were reviewed (total scans: 3,411). Bilateral frontal extracerebral fluid collections were found in 94 infants under 1 year of age. Eighty-two infants had computed tomography scans as part of the evaluation for macrocrania. Thirteen patients had the typical findings of benign extracerebral fluid collections but otherwise were completely asymptomatic. Longitudinal observation for up to 30 months failed to reveal any changes in neurologic status of these patients. Benign extracerebral fluid collections are a relatively common cause of macrocrania in infants. The presence of these fluid collections is not of immediate concern, providing that clinical evaluations fail to identify either neurologic or developmental abnormalities.