Neuropsychological follow-up in neonatal screening: issues, methods and findings

There are several ongoing studies of psychological outcome in children identified through neonatal screening with phenylketonuria, congenital hypothyroidism or congenital adrenal hyperplasia. These studies document the reduction in mental retardation, learning difficulties and behaviour problems associated with neonatal screening. They also describe other behavioural changes resulting from these disorders. Some behavioural changes are transient or preventable with early diagnosis and treatment, whereas some appear to be irreversible, reflecting permanent brain effects of abnormalities associated with the disease. Despite the variety of disorders studied, there are commonalities in approach and issues, including a developmental neuropsychological perspective resulting in behavioural assessments specific to the disorder and its likely manifestations, a recognition that behaviour may change across time in association with brain development and an understanding of the neural mechanisms underlying the behavioural changes. Assessments go beyond IQ, and include specific intellectual abilities, social behaviour, temperament, behaviour problems and identity. Behavioural changes are related to specific characteristics of the disease and its treatment, including the timing of exposure to abnormal hormones and/or neurotransmitters, the severity of the disease, and the age at initiation and adequacy of treatment. These studies provide information about the ways in which hormones and neurotransmitters affect the development and ongoing function of the brain, and an understanding of the ways in which neonatal screening results in improved psychological outcome. They also provide models for psychological follow-up of other disorders detected through neonatal screening.     

BIT-mapped somatosensory evoked potentials in the fragile X syndrome

Middle-latency somatosensory evoked potentials (MLSEPs) were recorded from 19 scalp electrodes in ten male patients with the fragile X (fraX) syndrome and nine normal controls. One fraX patient was found presenting the so-called “giant” MLSEPs with an amplitude of N60 of about 60 μV and of 40 μV after stimulation of the right and left median nerves, respectively. Tapping of the right hand, in the same patient, induced the appearance of left parietal evoked EEG spikes. These findings further support the already suggested similarity between the epileptic picture of several fraX patients with that of the benign childhood epilepsy with centrotemporal spikes. Color mapping of the MLSEPs recorded in the remaining nine patients, when compared with the control group, showed an abnormally large N30 over the frontal regions, together with an increase in amplitude of P27, over the parietal areas, and of N60 and P100 which also presented abnormal field distributions, being represented preferentially over the frontal regions. These data could suggest the existence of a cortical dysfunction mostly involving the frontal lobes (supplementary motor area, in particular) in the fraX syndrome which could support many behavioral changes usually observed in these patients.

Résumé

Les potentiels évoqués somesthésiques à latence moyenne (MLSEPs) du nerf médian ont été enregistrés avec 19 électrodes chez dix sujets avec le syndrome du chromosome X fragile (fraX) et neuf sujets normaux. Nous avons observé un sujet avec fraX et des MLSEPs géants et une amplitude de l'onde N60 de 60 μV après stimulation du nerf médian droit et de 40 μV après stimulation gauche. Après le toucher de la main gauche, chez le même sujet, on a observé l'apparition de pointes épileptiques pariétales à l'EEG. Ces résultats confirment l'hypothèse déjà proposée de la similitude entre l'épilepsie présentée par quelques sujets avec fraX et l'épilepsie bénigne de l'enfant avec pointes centrotemporales. La cartographie des MLSEPs obtenue chez les neuf autres sujets et confrontée à celle du groupe contrôle a mis en évidence une onde N30 avec amplitude anormalement augmentée sur les régions frontales, une augmentation de l'amplitude de P27 sur les régions pariétales, et de N60 et P100, qui montraient aussi une anormalité de la distribution topographique ; en effet, elles étaient mieux représentées sur les régions frontales. Ces données peuvent indiquer l'existence d'un dysfonctionnement des lobes frontaux (en particulier de l'aire motrice supplémentaire), dans le syndrome du chromosome X fragile, qui peut se corréler à plusieurs modifications du comportement généralement observées chez ces patients.     

Transcatheter embolization of coronary artery fistula with controlled release coils

ABSTRACT The treatment for large congenital coronary cameral fistulas has been surgical but with advances in interventional catheterization techniques transcatheter embolization of these fistulas with coils or detachable balloons is now possible. This report describes occlusion of a congenital coronary arteriovenous fistula in a 6-year-old girl.     

Dexamethasone and bacterial meningitis in Pakistan

The objective of this study was to assess, in a developing country setting, the effect of dexamethasone therapy on bacterial meningitis outcomes. A prospective double blind placebo controlled trial was conducted in 89 children aged from 2 months to 12 years suffering from bacterial meningitis. Neurological, developmental, and hearing assessments were conducted at one, four, and 12 months after discharge. Forty eight patients received dexamethasone and 41 placebo. Initial antimicrobial drugs used were ampicillin and chloramphenicol. For all patients at the time of admission the mean duration of illness was 5.7 days; 47% had had seizures and 56% had impaired consciousness. Seventeen of 89 (19%) patients died. The mortality for the dexamethasone group was 25% as compared with 12% in the group receiving placebo. Presentation to the hospital after four days of symptoms and with impaired conscious state were independent predictors of death. Of the dexamethasone group survivors, 26.5% had neurological sequelae and 42.3% had hearing impairment, whereas in the placebo group it was 24% and 30% respectively. Altered state of consciousness was a predictor of neurological sequelae. The presence of neurological sequelae and high cerebrospinal fluid protein independently predicted hearing loss. No beneficial effect of dexamethasone was observed on morbidity or mortality of this group of patients with bacterial meningitis. Dexamethasone is therefore not useful in developing countries as adjunctive treatment in patients seriously ill with bacterial meningitis, who present late for treatment and have been partially treated.     

Coronary artery fistula; coronary computed topography – The diagnostic modality of choice

Coronary artery fistulae (CAF) are rare anomalies. They are vascular communications between the coronary arteries and other cardiac structures, either cardiac chambers or great vessels. There can be considerable variation in the course of a coronary artery fistula. We report a case of a coronary artery fistula between the left circumflex coronary artery and the right and left atria. CAF are often diagnosed by coronary angiogram, however with the advent of new technologies such as Coronary Computed Tomography Angiography (Coronary CTA) the course and communications of these fistulae can be delineated non-invasively and with greater accuracy.