A clinical picture of child and adolescent narcolepsy.

Although narcolepsy is rarely diagnosed before adulthood, symptoms often begin much earlier and can easily mimic psychiatric disorders in children and adolescents. Clinical experience from a pediatric sleep center is reviewed in 16 consecutive cases of polysomnographically proven narcolepsy with onset of symptoms by age 13 years. Only 1 of the 16 patients presented with the classic clinical tetrad of symptoms (sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis). Behavioral and emotional disturbances were present in 12 of 16 cases, with four patients appearing to have been misdiagnosed with a psychiatric disorder before recognition of the narcolepsy. Obesity appeared as an unexpected association in this case series, with 11 of the 16 narcoleptic patients found to be overweight at the time of diagnosis. The varied clinical presentations, polysomnographic findings, family history, and associated psychiatric symptoms are described. The importance of considering narcolepsy in the differential diagnosis of any child or adolescent with excessive sleepiness is emphasized.

Comprehensive management of trichotillomania in a young autistic girl.

The coexistence of trichotillomania and autistic disorder has rarely been reported in psychiatric literature. The current study describes successful treatment of trichotillomania in a young autistic girl, using combined clomipramine and behavioral therapy. Neither behavioral therapy, clomipramine, methylphenidate, buspirone, nor naltrexone was effective in monotherapeutic trials. We postulate a synergistic effect of combined treatment with clomipramine and behavioral therapy, suggesting that both pharmacological and behavioral treatment of hair pulling may be necessary for many patients. This model is consistent with the extant literature and suggests that future clinical trials of clomipramine for trichotillomania, in both developmentally disabled and normal subjects, must evaluate this multimodal approach.

Magnetic resonance imaging of the posterior fossa in autism.

The brainstem-cerebellar circuitry has been implicated in the pathophysiology of autism for several decades. Recent magnetic resonance imaging (MRI) studies of the posterior fossa have reported various abnormalities, the most noteworthy of which has been selective hypoplasia of the neocerebellar vermis. However, these initial MRI studies are limited by problems in both subject and control selection. The present study was undertaken to further investigate these MRI findings and the role of the cerebellum in autism, taking into consideration these methodologic issues. Eighteen high-functioning autistic subjects were recruited and matched with 18 normal controls on the basis of age, gender, IQ, race and socioeconomic status (SES). The midsagittal areas of the cerebellar vermis, vermal lobes, and the fourth ventricle were measured on 3 mm contiguous magnetic resonance images. Mean areas and standard deviations were comparable for all regions of interest and no statistically significant between-group differences were found. These negative findings argue against theories of autism based on gross structural abnormalities of the cerebellum. Previous reports of posterior fossa abnormalities may be related to technical and methodological factors, based on comparison of extant literature and recently available normative data.

Partial agonist activity of oxotremorine at muscarinic acetylcholine receptors in the embryonic chick heart.

Previous work has demonstrated that prolonged treatment of chick embryos in vivo with muscarinic agonists leads to a decrease in the number of muscarinic acetylcholine binding sites in the heart and a decrease in the sensitivity of isolated atria to the negative chronotropic response to muscarinic stimulation. We show here that treatment with the agonist carbachol leads to greater decreases in receptor number than does treatment with oxotremorine. Simultaneous treatment with oxotremorine and carbachol resulted in partial blockage in the maximal decrease in receptor number seen after treatment with carbachol alone. After treatment of embryos in vivo with carbachol to decrease the reserve of spare receptors in the atria, oxotremorine could no longer elicit a significant negative chronotropic response under conditions in which carbachol was still effective. These results demonstrate that oxotremorine is a partial agonist at the muscarinic acetylcholine receptor in the embryonic chick heart.