Arthrogryposis multiplex congenita and bilateral mid-brain infarction following maternal overdose of co-proxamol

We report a case of arthrogryposis multiplex congenita secondary to fetal hypokinesia in a 41-week gestation infant following antenatal central nervous system injury. The mother's pregnancy was complicated by an episode of attempted self harm, with an overdose of co-proxamol at 22 weeks of gestational age, and by the use of cocaine in combination with excess alcohol intake. Magnetic resonance imaging showed bilateral mid-brain cysts and marked atrophy of the basal ganglia and thalami.

Chiari I malformation in asymptomatic young children with Williams syndrome: clinical and MRI study

We report clinical and magnetic resonance imaging findings in two young children, aged 2 years 4 months and 3 years, with Williams syndrome. Both showed a mild global delay, although their neurological examination was completely normal. Their magnetic resonance imaging, however, showed Chiari I malformation and some non-specific changes in the centrum semiovale and in the white matter posterior to the lateral ventricles. Cerebellar tonsils were displaced through the foramen magnum 8.5 and 7.5 mm respectively. Our results suggest that Chiari I malformation can also be a frequent feature in subjects with Williams syndrome even in the absence of overt neurological signs suggestive of it. Whether these children might develop acute signs later is not known at present. Further studies are needed not only to evaluate the incidence of these findings in the global population of subjects with Williams syndrome but also to identify the children who are at risk for developing acute neurological signs.

Does the brain regenerate after perinatal infarction?

We have used registered serial magnetic resonance scans to assess the growth of the brain after perinatal infarction in six infants. The initial scans were performed at ages of 4 days to 8 weeks and follow-up studies were performed from 4 days to 21 weeks later. A three-dimensional volume acquisition was performed on each occasion. Rigid body translations and rotations were used to match the images obtained on each occasion. Subtraction of the first image from the second then provided an assessment of the growth of the brain that had occurred between the two examinations. In the early phase of infarction (up to 2 months) low signal areas with clearly defined margins developed at the site of infarction. In the late phase (2 months onwards) growth was seen in the brain at the margins of the infarct in each case, and the size of the infarcted region showed a marked decrease in size. The rate of growth of the brain into the infarcted area exceeded that of the surrounding brain in some cases and was less in others. Growth of undamaged tissue may provide an important mechanism for recovery of the developing brain.

Cerebral metabolism within 18 hours of birth asphyxia: a proton magnetic resonance spectroscopy study

Proton magnetic resonance spectroscopy (1H MRS) was performed within 18 h of birth (median 13, range 4-18 h) on 16 term infants with clinical features of birth asphyxia. Ten infants with no evidence of birth asphyxia were studied as controls at 5-18 (median 8) h after birth. To detect delayed impairments in cerebral energy metabolism, 15 infants suspected of asphyxia underwent 31P MRS at 33-106 (median 62) h of age. Choline, creatine, and N-acetylaspartate (NAA) were detected in spectra located to the basal ganglia in all infants. Lactate was detected in 15 of the 16 infants suspected of asphyxia, but in only 4 of the 10 controls (p < 0.05, chi 2). Glutamine and glutamate (Glx) was detected in 11 infants suspected of asphyxia and in three controls, but this difference was not significant at the 5% level. The spectra revealed no other significant differences between asphyxiated infants and controls. In the asphyxiated infants, there was a negative correlation between the ratio of lactate to creatine in the first 18 h of life and phosphocreatine/inorganic phosphate (PCr/ P(i)) at 33-106 h (p < 0.001). Five severely asphyxiated infants had PCr/P(i) < 0.75 (median 0.53, range 0.14-0.65), indicating a poor neurodevelopmental prognosis, and a further infant died before PCr/Pi could be measured. Ten infants had PCr/P(i) > 0.75 (1.03, 0.76-1.49). Median lactate/creatine was 1.47 (range 0.67-3.81) in the six severely affected subjects, 0.38 (0-1.51) in the latter group, and 0 (0-0.6) in controls (p < 0.0005, Kruskall-Wallis). These results suggest that, after birth asphyxia, cerebral energy metabolism is abnormal during the period when 31P MRS characteristically gives normal results. 1H MRS might be of value in predicting which infants are likely to suffer a decline in cerebral high energy phosphate concentrations and subsequent neurodevelopmental impairment.

Rapid mitochondrial probes for analysis of polymorphisms in Fusarium oxysporum special forms

A method is described for the production of simple mitochondrial DNA probes from filamentous fungi for the partial characterization of mitochondrial DNA without the need for cloning, gradient centrifugation or PCR amplification. A probe (P449) consisting of a 3.38 kb mitochondrial fragment from an isolate of Fusarium oxysporum special form cubense was used to determine RFLPs in restriction digests of total DNA from 28 isolates of F. oxysporum from a variety of hosts and locations. The probe showed mtDNA polymorphisms within and between different special forms.

Hypoxic ischaemic encephalopathy: early magnetic resonance imaging findings and their evolution

Eighteen term infants with hypoxic ischaemic encephalopathy (HIE) were studied with serial magnetic resonance imaging of the brain for up to two months following birth. Important early findings included brain swelling, cortical highlighting, diffuse loss of grey/white differentiation and loss of signal in the posterior limb of the internal capsule (PLIC). These signs were easier to identify on T1-weighted spin echo or inversion recovery sequences than on T2-weighted spin echo sequences. Brain swelling was only seen in the first seven days and was present in all grades of HIE. All other signs persisted and were associated with the subsequent development of major structural changes in the brain. The exact pattern of injury was best identified after the first week of life once the signs of brain swelling had cleared.

Cranial ultrasound and magnetic resonance imaging in hypoxic-ischaemic encephalopathy: a comparison with outcome

Forty term infants with hypoxic-ischaemic encephalopathy were assessed during the neonatal period with cranial ultrasound and MRI, and the findings were compared with outcome at one year of age. 38 had abnormalities on ultrasound and all had changes on MRI. The incidence of changes in the basal banglia/thalami and periventricular white matter was much greater with MRI than with ultrasound. Changes in the basal ganglia and thalami on MRI were associated with a poor outcome if they had also been detected with ultrasound. However, MRI identified four small infarcts which were not detected by ultrasound. There was no consistent association between periventricular white matter change on MRI and outcome. Regular ultrasound scanning identified all infants with a poor outcome. A normal ultrasound or isolated findings of intraventricular haemorrhage, subarachnoid haemorrhage or transient flares were associated with a normal outcome in 13 of 14 infants.

Proton spectroscopy of the neonatal brain following hypoxic-ischaemic injury

Proton magnetic resonance spectroscopy was used to examine, within the first month of life, the brains of 11 infants born at term--10 with signs of hypoxic-ischaemic encephalopathy (HIE) and one who was neurologically normal at birth. All the infants had peak resonances on their spectra which could be assigned to N-acetyl-aspartase (NAA), choline-containing compounds (Cho) and creatine plus phosphocreatine (Cr). When neurodevelopmental outcome at one year was correlated with initial spectroscopy findings, the NAA/Cho and NAA/Cr ratios reflected clinical outcome. This study suggests that proton spectroscopy not only provides new information about biochemical changes occurring in the brains of infants with HIE, but also may help to predict outcome within the first month of life.

MRI: early onset of changes in Wallerian degeneration

T2-weighted spin echo scans were performed on a neonate and two adults aged 42 and 60 years within 2 weeks of the onset of infarction in the frontoparietal region of the brain. Areas of increased signal intensity were observed in the anterior and posterior limbs of the internal capsule in the infant and in the posterior limbs of the internal capsules in the adults. Although these signal changes were typical of the chronic phase of Wallerian degeneration, their onset was much earlier than the 10-14 weeks previously described for this stage in adults. The low level of myelination of white matter tracts at birth, and the relatively sparse myelination of the parietopontine tract may account for the rapid onset of changes in these patients which more closely follows the time course described pathologically for Wallerian degeneration in unmyelinated fibres.

Athetoid cerebral palsy with cysts in the putamen after hypoxic-ischaemic encephalopathy

Three cases of athetoid cerebral palsy after hypoxic-ischaemic encephalopathy (HIE) are reported. All three neonates had haemorrhagic lesions in the basal ganglia and thalami on magnetic resonance imaging (MRI). Prior cranial ultrasound had detected the lesions in only two cases. In all three children athetoid movements began within the first year of life. Follow up MRI scans showed bilateral symmetrical cystic lesions in the posterior putamen. Although haemorrhagic lesions within the basal ganglia are a common MRI finding in neonates with HIE, few of these babies develop athetoid cerebral palsy. We believe this to be the first report of discrete cystic lesions found in the basal ganglia of children with athetoid cerebral palsy.

Infants of diabetic mothers: a prospective study of neonatal complications in Harare, Zimbabwe

Complications in 42 newborn infants of diabetic mothers (IDM), both insulin- and non-insulin-dependent, were studied prospectively over a period of 16 months at Harare Maternity Hospital. Hypoglycaemia, the most common complication observed, was present in 23 (55%): only seven of these were symptomatic. In 21 of these 23 cases, blood glucose was stabilized during the first 24 hours of life. Jaundice and transient tachypnoea were each seen in 12 cases (29%). There were no cases of respiratory distress syndrome. One infant had polycythaemia requiring partial exchange transfusion. No life-threatening congenital malformations were seen. All infants were given special care initially and in the majority of cases this could be discontinued after 24 hours. With simple interventions, the morbidity of IDM born was found to be comparable to levels reported from developed countries.

Congenital myotonic dystrophy: respiratory function at birth determines survival

The clinical features of 14 neonates with congenital myotonic dystrophy were retrospectively reviewed. These babies represent all the new cases of congenital myotonic dystrophy seen in this department since 1982. Twelve babies were referred because of either difficulties in diagnosis or difficulties in the management of their respiratory problems. Of the 14 babies, 13 had birth asphyxia, 11 were premature, and four had intrauterine growth retardation. Ten babies required artificial ventilation from birth. Abnormalities on chest radiography included thin ribs (n =9) and raised right hemidiaphragms (n = 5). Recurrent episodes of collapse and consolidation of the lungs secondary to poor swallowing occurred in all ventilated babies. All babies ventilated for longer than four weeks died of respiratory complications before the age of 15 months. One baby was successfully extubated after diaphragmatic plication, but he died a few months later. Duration of ventilation was the best guide to prognosis.