A long-term follow-up of cognitive, emotional, and behavioural sequelae to Reye syndrome

Eighteen adolescents who had survived Reye syndrome (RS) in early childhood were assessed on cognitive, emotional, and behavioural variables in a second follow-up study tracking this group. Siblings were used as controls. The entire group with RS had survived with no obvious neurological damage at the first follow-up study. Indeed, current findings suggested that long-term cognitive, emotional, and behavioural functioning was comparable to siblings in approximately half of the group with RS. However, two factors were associated with a less favourable outcome. Cognitive, emotional, and behavioural functioning were significantly poorer in the subgroup of survivors whose illness had occurred in the first year of life. In addition, loss of consciousness, although the association with poor outcome was not as noticeable, was also associated with relative deficits on some scales of cognitive ability. Many of these deficits had not been obvious at the first follow-up and the importance of neurodevelopmental factors are considered. Finally, the implications of these findings for research and interventions in RS and other such encephalopathies are discussed.

The mechanism of inhibition of beta-oxidation by aspirin metabolites in skin fibroblasts from Reye's syndrome patients and controls

The effects of aspirin metabolites on beta-oxidation were studied in skin fibroblasts from eight typical Reye's syndrome (RS) patients and controls. RS patients' cells did not differ from controls in rates of palmitate oxidation or in the three component activities of the mitochondrial trifunctional enzyme (MTE), indicating no inherited beta-oxidation defect. Aspirin metabolites salicylate, hydroxyhippurate and gentisate, but not aspirin, directly inhibited palmitate oxidation in control and RS cells. RS cells were significantly more sensitive to inhibition than controls at 0.5 to 5 mM salicylate. Inhibition was concentration-dependent and reversible. Inhibition did not occur in fibroblasts lacking activity of the long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) activity of MTE. Salicylate was therefore inhibiting beta-oxidation at this step. Hydroxyhippurate and salicylate reversibly inhibited HAD activities in extracts of control and RS cells. Studies with pure short-chain HAD and LCHAD (MTE) showed hydroxyhippurate and salicylate were competitive inhibitors of the former but mixed (not competitive) inhibitors of the latter. Both compounds inhibited the combined, three-step, MTE reaction measured in the physiological direction. We conclude that (1) salicylate and hydroxyhippurate decrease beta-oxidation in intact cells by reversible inhibition of LCHAD activity of the MTE, and (2) beta-oxidation in RS cells is inherently more sensitive to inhibition by low concentrations of salicylate than controls.

The changing clinical pattern of Reye's syndrome 1982-1990

OBJECTIVE

To describe trends in the clinical pattern of Reye's syndrome in the British Isles between 1982 and 1990; and to determine the relation between any changes and the June 1986 warnings against the use of aspirin in children.

DESIGN

Development, and application to reported cases, of a scoring system designed such that patients showing the typical clinical and pathological features of 'classical' Reye's syndrome scored highly. The relations between 'Reye scores' and a number of explanatory variables were explored using multivariable analysis.

SETTING

British Isles.

SUBJECTS

445 cases fulfilling the Reye's syndrome case definition reported to the surveillance scheme between January 1982 and December 1990.

MAIN OUTCOME MEASURE

Individual 'Reye score'.

RESULTS

Cases with high scores were more likely to have occurred in the 4 1/2 year period before June 1986 compared with the subsequent period (p < 0.006). Numbers of cases in the low and intermediate score categories declined by about 50% after June 1986, whereas those in the high category fell by 79%. High scorers were more likely to have received aspirin (p < 0.0001) and were older than intermediate and low scorers (p < 0.008). No relation was identified between score and season of onset.

CONCLUSIONS

The decline in Reye's syndrome after the aspirin warnings cannot be explained entirely, as has been proposed, by improved diagnosis of 'Reye-like' inherited metabolic and other disorders: this would not account for the greater decline of the high scoring subgroup which also contained those cases most likely to resemble 'classical' Reye's syndrome and to have received aspirin. This study provides further evidence for the role of aspirin in a subset of cases meeting the standard diagnostic criteria for Reye's syndrome and supports the need to consider this disorder as a heterogeneous group of conditions including Reye-like inherited metabolic disorders.

Metabolism of paracetamol in children with chronic liver disease

OBJECTIVE

To study the metabolism of single doses of paracetamol in paediatric patients with chronic liver disease admitted to a hospital liver disease clinic.

RESULTS

Thirteen paediatric patients, aged 7 months to 12 years, with chronic liver disease of varying severity were studied. In these children, paracetamol elimination half-life was negatively correlated with serum albumin and positively with prothrombin time, as previously reported in adults with liver disease. The rate constant of glucuronide formation was higher in the children with liver disease compared to the value reported in healthy children of similar ages. The rate constant of the formation of paracetamol sulphate was no different from that in normal children. The 36 h urinary paracetamol glucuronide to sulphate ratio was 1.4 (95% CI 0.8 to 1.7). This mean ratio was higher than in healthy children (0.81 and 0.75) but not significantly so, probably because of a Type 1 error due to the inevitable small sample size arising from the nature of the population being studied.

CONCLUSION

The present study provides reassuring additional data to indicate that, at least for single doses, there is no cause for concern in the use of paracetamol in children with chronic liver disease.

Assay of paracetamol and its metabolites in urine, plasma and saliva of children with chronic liver disease

A high-performance liquid chromatographic (HPLC) assay of paracetamol and its metabolites is described. The method for quantifying the metabolism of paracetamol in children with chronic liver disease and the good correlation between plasma and salivary concentrations of paracetamol is demonstrated. Despite an increasing bias between the two methods with increasing concentration of paracetamol, it is concluded that salivary assay is satisfactory for characterising paracetamol pharmacokinetics in the group of patients studied.

Paediatric consultation patterns in general practice and the accident and emergency department

The age, sex, source of referral and diagnosis of children brought to a paediatric accident and emergency department by their parents were compared to those consulting their general practitioner. A simultaneous, prospective review of these consultations was carried out over a six-week period in an inner-city paediatric teaching hospital and a group practice in a socially deprived urban area. 730 children less than 13 years of age who presented for a new consultation were seen. 629 (86%) presented initially to the general practitioner, who dealt with all but 25 (4.0%) without onward referral to the accident and emergency department. 127 consultations took place at the accident and emergency department, of which 104 (82%) were parental referrals. There was no sex difference in children seen by the general practitioner. There was a decreasing trend with increasing age in the proportion of children who consulted the general practitioner, perhaps due to the higher frequency of injury in the older children. Over three quarters (77%) of injured children were brought directly to the accident and emergency department, compared with only 4% of children without injuries (p < 0.001). Of 22 children with injuries who presented to the general practitioner, only 4 (18%) required onward referral. General practitioners met the great majority of the paediatric workload generated by the practice. Audit between primary and secondary care gives a more reliable picture than data from only one source. Injured children are more likely to be taken to the accident and emergency department. Further study of the severity of injury in children is required to determine if there is potential to reduce parental referrals to accident and emergency departments.

An audit of dermatology in a paediatric accident and emergency department

Two studies were undertaken of patients with dermatological disorders who attended the Accident and Emergency (A&E) Department of the Royal Belfast Hospital for Sick Children during 1990-1991. The aims were to review diagnostic accuracy and assess the benefits of an open-access consultant dermatology clinic. A retrospective survey of 14,340 new attendances at the A&E department over a 7-month period found that 540 of these (4%) had a primary dermatological disorder. In 26% no diagnosis had been made although only 10% were referred for a specialist opinion. A 2-month prospective study of patients who attended the department and were referred to a consultant dermatology open-access clinic revealed overall diagnostic accuracy of 66% (+/- 2 SEM). Individual rates of diagnostic concordance between junior doctor and consultant were 59% for skin infections and 77% for papulosquamous disorders. The open-access clinic allowed prompt referral for correct diagnosis and initiation of appropriate management.

Current concepts in Reye's syndrome

Reye's syndrome is an acute metabolic encephalopathy largely affecting children and adolescents. Its aetiopathogenesis, although controversial, is at least partially understood. Its study has helped to create a greater awareness of inherited disorders of intermediary metabolism. Although these are individually rare, when combined they constitute a significant cause of morbidity and mortality.

Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency--diagnosis, plasma carnitine fractions and management in a further patient

Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase (LCHAD), the third enzyme of the mitochondrial beta-oxidation pathway, carries out the dehydrogenation of 3-hydroxyacyl-CoA compounds of 12-18 carbon length. To date only nine cases of LCHAD deficiency have been documented. We report a further patient who as a neonate developed non-specific gastrointestinal symptoms and at 5 months of age cardiomyopathy, recurrent hypoketotic hypoglycaemia and gross alterations of plasma carnitine fractions. Dietary management with medium chain triglycerides led rapidly to clinical improvement. There was a close correlation between the clinical condition, plasma carnitine fractions and cardiac function. At 2 years of age she is developing normally.

The phenylpropionic acid load test: experience with 72 children at-risk for beta-oxidation disorders

The urinary excretion of metabolites of orally administered phenylpropionic acid (PPA) in 72 children, aged 2 days to 16 years, thought to be at-risk of medium acyl CoA dehydrogenase deficiency has been studied. Forty had presented as Reye Syndrome, 9 as a Reye-like syndrome and 24 were sibs of decreased RS, sibs of RLS cases or sibs of infants who had died suddenly and without explanation where an autopsy revealed the presence of very heavy fatty infiltration of the liver. These studies demonstrated that PPA metabolites are maximally excreted during the 3 hours following the oral load and that this urine collection should be diagnostic. PPA loading is a relatively simple, safe test which is part of the investigation of a patient suspected of having an inborn error of metabolism.

A sibling-controlled study of intelligence and academic performance following Reye syndrome

The authors compared the intellectual, cognitive and academic abilities of 22 survivors of Reye syndrome attending normal schools with the sibling nearest in age as control. The British Ability Scales, visual and verbal IQ, short-term memory scales and attainment tests were administered to all children. Reye syndrome children as a group differed significantly from the controls only on the basic number skills test. However, children with severe encephalopathy and those whose illness occurred in infancy had significant deficits on many of the tests. 18 children recovered without requiring 'additional educational provision'; the mean IQ of the 22 Reye syndrome children was 101. Nonetheless, these children's poor performance on the basic number skills test has important implications for teachers, and careful monitoring of future educational performance is essential.

Trends in the incidence of Reye's syndrome and the use of aspirin

In 1986 there was a public warning in the United Kingdom about a link between the consumption of aspirin and Reye's syndrome. To find out if the use of aspirin and paracetamol in children had altered, and whether the incidence of Reye's syndrome had changed since a previous study, parents were interviewed in Belfast and London, and the British Reye's Syndrome Surveillance System data were reviewed. Children with febrile illnesses were 17 times more likely to have received aspirin before admission to hospital in 1985/6 compared with 1988/9. Only 21 Belfast parents (40%) and 13 London parents (27%) had heard of Reye's syndrome and only 12 in Belfast (23%) and seven in London (15%) knew of its association with aspirin, suggesting a continuing need for public education. Cases of Reye's syndrome declined both in numbers (from a peak of 79 in 1983/4 to 19 in 1988/9) and in median age. Of the 418 reported cases, the diagnosis was subsequently revised in 89, most often (in 31 of 89, 36%) to 'inborn errors of metabolism'.

Children with gastroesophageal reflux with or without partial thoracic stomach (hiatal hernia) have normal gastric emptying

Gastric emptying was measured using a modification of the double-sampling dye dilution technique in 16 children with gastroesophageal reflux and partial thoracic stomach (hiatal hernia), 13 with reflux per se, and 12 controls with nonspecific vomiting. No differences could be demonstrated between the rate of emptying in these groups. Our study failed to provide a rational explanation for the copious projectile vomiting that is a frequent manifestation of these disorders.

Preadmission antipyretics in Reye's syndrome

The parents of 106 children who had had Reye's syndrome and those of 185 comparison children who had febrile illnesses were interviewed in order to compare preadmission medication exposure rates in the two groups. Although comparable proportions of case and comparison patients had taken antipyretics in the three weeks before admission, a significant excess of cases (59% compared with 26% in the comparisons) had been given aspirin, whereas significantly more comparison children (49% compared with 25% in the cases) had taken paracetamol. There was an excess exposure to aspirin in children under 5 years of age; the excess observed in older patients just failed to reach significance. Separate analyses within Northern Ireland and England also showed a case-comparison difference. A significant correlation was shown between aspirin (but not paracetamol) exposure and the closeness with which cases conformed to the diagnostic criteria of Reye's syndrome, measured by an artibrary score. The many difficulties of conducting and interpreting the findings of an epidemiological risk factor study of an association between aspirin and Reye's syndrome are reviewed and emphasised. Inherent biases were present in this as in previous studies and it did not conform to the classical case-control design. Nevertheless the findings suggested that an association between Reye's syndrome and preadmission aspirin may exist in some children.

Reye's syndrome: assessment of intracranial monitoring

Direct measurements of arterial blood pressure and intracranial pressure were recorded in 39 patients aged 3.6 months to 5 years 11 months with Reye's syndrome judged to be stage 2 or beyond. Of 33 patients who survived, 27 made a full recovery and six were severely handicapped. Measurement of cerebral perfusion pressure, which is greatly reduced in the more severe forms of Reye's syndrome, was a better guide to prognosis and management than intracranial pressure alone. The findings emphasise that maintenance of cerebral perfusion pressure is essential if mortality and morbidity are to be reduced. Intracranial monitoring is mandatory in all but the mildest cases of Reye's syndrome.

Twenty year review of duodenal ulcer

Of 31 patients (18 male and 13 female) followed up 13-29 years after diagnosis, recurrent or persistent duodenal ulcer had occurred in four. In 22 (71%) gastrointestinal symptoms persisted into adult life, although only abdominal pain was significantly more frequent than in 126 controls.

Hepatocellular carcinoma associated with congenital macronodular cirrhosis in a neonate

Hepatocellular carcinoma is rare in infancy. This report describes the first documented case of congenital hepatocellular carcinoma associated with macronodular cirrhosis.

Parents' understanding of coeliac disease and diet

Parents of 50 children with coeliac disease were questioned about their knowledge of the disorder and the child's dietary compliance. Twenty of 50 parents admitted that compliance was less than strict. This correlated with poor knowledge of the disease which in turn was related to the family's social status. Membership of the Coeliac Society (23 of 50) correlated with both parental understanding and dietary compliance. Greater emphasis on dietary compliance and education of parents and patients is required.

Reye's syndrome

Reye's syndrome, an uncommon childhood encephalopathy of uncertain aetiology, is an important cause of mortality and permanent handicap. Since its recognition treatment has changed, current management focusing upon prevention or control of raised intracranial pressure. Prognosis is radically improved by early recognition and prompt transfer to a specialist centre.

Clinical features and prognosis of Reye's syndrome

Twenty three sporadic cases of Reye's syndrome diagnosed according to widely accepted criteria were seen between 1979 and 1982. The patients were younger than those reported from North America (median age 9 months), girls were twice as common as boys, and the syndrome presented twice as frequently in the summer 6 months. The annual incidence was 1.4 cases/100 000 among children aged less than 4 years. The prodrome consisted of upper respiratory symptoms in 61% of the children and even less specific features in more than 25%; two patients had varicella. Six of the 23 patients presented after a prodrome of less than 24 hours with 'acute collapse', simulating 'near miss' cot death associated with profound hypoglycaemia, and in four of these there was an unfavourable outcome. Intensive care methods including judicious fluid restriction coupled with 'prophylactic' hyperventilation (87%), direct monitoring of intracranial pressure (70%), and barbiturate coma (52%) achieved neurologically intact survival in 74% of patients. Failure to recognise the syndrome early enough or to manage it appropriately resulted in four deaths. To help reduce overall mortality in the United Kingdom paediatricians have a duty to acquaint family doctors and emergency department staff of the earliest clinical features of Reye's syndrome and of the need for immediate hospital referral.

Intractable diarrhoea associated with continuation of cytotoxic chemotherapy during acute infective enteritis

Severe intractable diarrhoea which required prolonged parenteral nutrition is reported in a child with acute leukaemia. The enteropathy is likely to have been the consequence of continuing cytotoxic therapy during an episode of acute infective diarrhoea. It is postulated that the inhibition of crypt mitotic activity prevented the rapid recovery of small intestinal mucosa normally seen after viral infection and resulted in persisting small intestinal dysfunction. The inter-relationship between viral and cytoxic-induced enterocyte damage is discussed and the risks of continuing therapy under such conditions is considered.

Serosal miliary Crohn's disease in association with probable coeliac disease

A 2-year-old boy with peritoneal miliary Crohn's disease is described. In addition to vague gastrointestinal symptoms, ascites was a prominent feature. The jejunal mucosa was markedly atrophic, compatible with a diagnosis of coexistent coeliac disease.

Plasma amino acid ratio as an index of hepatocellular maturity in the neonate

A preprandial plasma amino acid molar ratio [(isoleucine + leucine + valine)/(tyrosine + phenylalanine)] has been studied in 33 neonates of mean gestation approximately 34 weeks. 19 infants were fed a formula containing 2.5 protein/dl with a high casein content (group 1), whilst 14 received milk of 1.8 g protein/dl largely derived from whey. Although total amino acid levels were significantly higher in group 1 (p less than 0.001), the amino acid molar ratio was similar in each group. This ratio correlated directly with gestational age (r = +0.76; p less than 0.001) which, on multiple regression analysis, accounted for 57% of its variability. The effects upon the ratio of infant's sex, cholestasis, and hepatic enzyme induction are also discussed.

Jejunal crypt cell abnormalities associated with methotrexate treatment in children with acute lymphoblastic leukaemia

Jejunal mucosal crypts were examined in jejunal biopsies from eight children with acute lymphoblastic leukaemia who had recently received methotrexate treatment. By comparison with biopsies from children under investigation for suspected malabsorption crypt mitosis was significantly reduced and showed a negative correlation with the dose of methotrexate given prior to biopsy. The three major cell types were studied under light and transmission electron microscopy. Gut endocrine cells were unaffected by therapy and immature crypt enterocytes showed only patchy degenerative abnormalities. By contrast a number of Paneth cells showed striking structural alterations with vacuolar dilatation of the cytoplasm. The extent of this correlated with the time since methotrexate treatment rather than its dose and may have been a functional response rather than of a toxic nature.

Changes in N-terminal glucagon-like immunoreactivity and insulin during short-term gluten challenge in childhood coeliac disease

Sixteen patients (aged 3.5-14.3 years) with normal jejunal mucosa, originally diagnosed as having coeliac disease at least 18 months before, were started on gluten challenge. The 'end point' of challenge was significant deterioration in jejunal mucosa morphologically and morphometrically. Studies carried out both before and after challenge included intestinal absorption of D-xylose and glucose, and release of insulin and N-terminal glucagon-like immunoreactivity (N-GLI). After gluten challenge, there were significant increases in plasma N-GLI at both 45 (P less than 0.05) and 120 minutes (P less than 0.03) after oral glucose. Significant reduction occurred in glucose absorption at 45 minutes (P less than 0.04), in one-hour D-xylose absorption (P less than 0.01) and fasting serum cholesterol (P less than 0.01). Plasma N-GLI showed significant negative correlations with D-xylose absorption (P less than 0.003) and serum cholesterol (P less than 0.004).

Small bowel enterocyte abnormalities caused by methotrexate treatment in acute lymphoblastic leukaemia of childhood

Jejunal biopsy specimens from 10 children with acute lymphoblastic leukaemia on methotrexate treatment were compared with 10 from children being investigated for diarrhoea or failure to thrive. In association with methotrexate treatment on both light and electron microscopy, there were marked morphological abnormalities in the villus enterocytes. These consisted of a striking distention of the lateral basal intercellular spaces, cell vacuolation and patchy necrosis and was most marked when methotrexate treatment was given between 24 and 72 h before biopsy. Two mechanisms may be involved: an early direct toxic effect on the mature enterocyte coupled with interference with crypt cell generation, possibly causing ageing and loss of cells proximal to the normal extrusion zone. These pathological changes may account for the malabsorption in association with methotrexate treatment.

Enterotoxic effect of methotrexate: does it influence the drug's absorption in children with acute lymphoblastic leukaemia?

Images

Can food influence the absorption of methotrexate in children with acute lymphoblastic leukaemia?

Serum levels of methotrexate (MTX) were measured in 10 children with acute lymphoblastic leukaemia over a 4 hour period after oral administration. The drug was given to each child on three occasions: first, with no food, then with a milky meal, and finally with a citrus meal. Peak serum MTX levels were significantly reduced by the milky meal and both meals delayed drug absorption in most children. The area under the absorption curve was also significantly reduced by the milky meal. Thus, for maximum serum levels, MTX should not be given with food, and if patients are to be grouped on the basis of their MTX absorption profile this should be determined under standard conditions in relation to meals.

Critical assessment of small bowel biopsy in children

176 biopsies of small bowel mucosa taken during a 5-year period from 162 children were reviewed, and 92 of them were subjected to quantitative measurement using surface/volume ratio and intraepithelial lymphocyte counting. There was good general agreement between stereomicroscopical appearance of fresh tissue, routine pathology reporting, and our independent histological assessment. Most of those in which there was divergence of opinion (11--15%) had intermediate mucosal changes. There was a significant difference between the surface/volume ratio for each of the three grades of histology (P less than 0.001, less than 0.001, less than 0.01), indicating a relationship between qualitative and quantitative methods of assessment. The range of measurements in intermediate biopsies overlapped those of the other two grades. In the 92 biopsies there was a correlation between surface/volume ratio and intraepithelial lymphocyte count (r = -0.56; P less than 0.001) which may reflect our clinical experience, in that 88% of the biopsies were graded as either normal or flat (probable coeliac disease). Very short children had shorter villi than those with nonspecific diarrhoea and a more normal height.

Hypochondroplasia

Clinical, radiological, and genetic features are described in 3 patients with hypochondroplasia. Early recognition of this disorder is possible from the abnormal body proportions with short limbs and lumbar lordosis without facial stigmata of achondroplasia. Radiological confirmation is possible provided a full skeletal survey is made. Two of our patients had a large head.

The "mandibular mantle"--a sign of rickets in very low birth weight infants

Mandibular periosteal new bone formation (the "mandibular mantle") is described in very low birth weight infants with other signs of severe metabolic bone disease. In infants with onset of dyspnoea and apnoea, between two and three months of age, this mandibular change suggests that the lung disorder is of skeletal, rather than pulmonary origin and aids in differentiation therefore, from the Mikity-Wilson Syndrome (pulmonary dystmaturity).