Safety and immunogenicity of TETRActHIB (a vaccine combining DTP vaccine and Haemophilus influenzae type B conjugate vaccine) administered to infants at 6, 10 and 14 weeks of age.

The safety and immunogenicity of TETRActHIB (a vaccine combining diphtheria and tetanus toxoids-pertussis vaccine (DTP) with Haemophilus influenzae type b (Hib) conjugate vaccine (polyribosyl ribitol phosphate conjugated to tetanus protein) (PRP-T)) was assessed in 131 Cape Town infants immunized at 6, 10 and 14 weeks of age. Serological responses to all component antigens were measured before the first dose and at 18 weeks of age. In addition, anti-PRP antibodies were measured at 9 and 18 months of age to determine long-term immunogenicity. The vaccine was well tolerated by infants and no significant side-effects were reported. Responses to Hib at 18 weeks of age were good in that most infants achieved a level of anti-PRP antibodies > or = 0.15 microgram/ml, indicative of short-term protection, and 70% achieved a level > or = 1 microgram/ml, indicative of long-term protection. The proportions of children with protective levels > or = 0.15 microgram/ml and > or = 1 microgram/ml were similar at 9 and 18 months of age, i.e. approximately 75% and 45%, respectively. Responses to tetanus and diphtheria toxoids were excellent and all infants achieved protective serological levels. Responses to pertussis were moderate in that approximately 65% achieved 'protective' serum levels of pertussis agglutinins, i.e. titres > or = 320. In conclusion, this study has shown that the DTP/PRP-T vaccine is safe, immunogenic and well tolerated in infants immunised at 6, 10 and 14 weeks of age. TETRActHIB is therefore suitable for inclusion in the World Health Organisation Expanded Programme on Immunisation (WHO EPI) schedule.

Numerical modeling for RF and microwave heating using FE comes of age.

This paper gives a brief resume of the numerical work carried out over the past decade at the Electricity Utilisation Group usingfinite elements for the characterization of RF and microwave heating systems. Maxwell's equations are solved in 3D while for coronas the Poisson's and particle continuity equations are solved in 2D. In addition work on modeling thin films and the use of parallel computing describes the latest work to emanate from the group.

Epidemiology of post-neonatal bacterial meningitis in Cape Town children.

Bacterial meningitis is a major cause of childhood morbidity and mortality in South Africa. However, comprehensive regional or national epidemiological data, essential for rational public health interventions, are lacking. The purpose of this 1-year prospective study, from 1 August 1991 to 31 July 1992, was to define the magnitude of the problem of childhood bacterial meningitis in Cape Town. The study group consisted of all children, aged > 1 month to < 14 years, who presented with proven bacterial meningitis at all the hospitals in the Cape Town metropolitan area. During the year 201 cases were identified: 101 (50.2%) were due to Neisseria meningitidis, 74 (36.8%) were due to Haemophilus influenzae and 26 (12.9%) were due to Streptococcus pneumoniae. The overall incidence rate (95% confidence interval) for children less than 14 years, 5 years and 1 year was 34 (30-40), 76 (65-88) and 257 (213-309) per 100,000 children, respectively. The rate was highest in black infants, 416 (316-545)/100,000. This was 2 times greater than the rate in coloured infants and about 4.5 times greater than the rate in white infants. The median age of all the children was 10 months. The ages of children with haemophilus and pneumococcal meningitis were similar, 9 and 7.5 months respectively (P = 0.43), while children with meningococcal meningitis were significantly older (22 months) than the others (P < 0.01). The overall case fatality rate was 5%, and 12.9% of survivors had significant neurological sequelae (disability) on discharge.

Plasma free iron: a possible cause of oedema in kwashiorkor.

BACKGROUND: Oedema is a sine qua non for the diagnosis of kwashiorkor yet the mechanisms leading to oedema remain ill defined. AIMS: To relate the plasma concentration of radical promoting 'free' iron to the degree of oedema in patients with kwashiorkor. SETTING: University teaching hospital. PATIENTS: Fifteen children with kwashiorkor, nine of whom had severe and six of whom had a moderate degree of oedema. METHODS: Plasma 'free' iron was measured as bleomycin detectable iron (BDI) and related to severity of oedema and plasma albumin concentration. RESULTS: BDI was significantly higher in the patients with severe oedema (20.5 v 6.75 mumol/l) whereas the albumin concentrations were similar (16 v 17 g/l). BDI was no longer present in any patients 30 days after admission. CONCLUSIONS: 'Free' circulating iron may contribute to the oedema of kwashiorkor, and its sequestration could hasten recovery and decrease morbidity and mortality.

Vitamin A status and therapy in childhood pulmonary tuberculosis.

Low plasma vitamin A levels (mean, 18.1 +/- 10.3 micrograms/dl, 62% below normal) were demonstrated in South African children with pulmonary tuberculosis. More extensive or severe disease (e.g., additional extrapulmonary tuberculosis) and low levels of retinol binding protein, prealbumin, and albumin were associated with low vitamin A levels. High-dose vitamin A therapy had no effect on disease outcome.

Bone marrow and chelatable iron in patients with protein energy malnutrition.

OBJECTIVES: To examine the iron status of malnourished children by comparing bone marrow iron deposits in children with protein energy malnutrition with those in well-nourished controls, and measuring chelatable urinary iron excretion in children with kwashiorkor. DESIGN: Bone marrow iron was assessed histologically in postmortem specimens from children with kwashiorkor or marasmus, and from controls. Twenty-four-hour urinary iron was measured in children with severe kwashiorkor, half of whom received 10 mg/kg of intramuscular desferrioxamine (DFO) on admission. SETTING: Red Cross War Memorial Children's Hospital, Cape Town. SUBJECTS: Thirteen children with kwashiorkor, 6 with marasmus and 16 well-nourished children underwent bone marrow examination. Urinary iron excretion was assayed in 17 children with kwashiorkor. RESULTS: Stainable iron was present in the bone marrow of half the children with kwashiorkor but in only 1 child in each of the other groups. The median iron excretion was 945.5 micrograms/24 hours in the DFO group compared with 28.5 micrograms/24 hours in the non-DFO group. CONCLUSIONS: There is an apparent excess of iron which may predispose to bacterial infections and free radical-mediated injury in children with kwashiorkor.

Misplaced iron in kwashiorkor.

OBJECTIVES: To determine the presence of radical promoting iron (non-protein-bound or loosely bound or free iron) in the plasma of children with kwashiorkor. DESIGN: The bleomycin assay was employed for the quantitation of free or loosely bound iron. SETTING: The Red Cross War Memorial Children's Hospital, Cape Town, Tertiary Care. SUBJECTS: Fifty children on admission with kwashiorkor: six with marasmus and twelve healthy well-nourished controls. RESULTS: Non-protein-bound iron was detected in the plasma of 58% of children with kwashiorkor but was absent in marasmic and healthy well-nourished children. CONCLUSIONS: The presence of radical promoting iron supports the hypothesis that a free radical injury probably plays a role in the pathogenesis of kwashiorkor and its removal may improve mortality.

The social, family and medical backgrounds of children with kwashiorkor presenting at a teaching hospital.

The social, family and medical backgrounds of 53 children hospitalised with kwashiorkor were compared with those of 106 children hospitalised for non-nutritional diseases to determine risk factors for severe nutritional disease in children presenting to a teaching hospital. The control children were matched for age, sex, race and the non-nutritional illness complicating the course of the children with kwashiorkor; in 80% of cases the reason for admission was either gastro-enteritis or pneumonia. A major difference between the groups was the educational status of the mothers. Only 57% of the mothers of the children with kwashiorkor were literate compared with 93% of the controls; 25% as opposed to 47% were married, and 36% as opposed to 72% received support from the father. There were no differences in the mothers' ages or use of contraception, or in the number of children they had. In all except 1 instance the child with kwashiorkor was the youngest or only child in the family, and the average sibling interval was 53 months. The types of dwellings occupied by the families were similar, but overcrowding was worse in the kwashiorkor group. Family income was below the household subsistence level in the vast majority of both groups, but significantly more of the kwashiorkor group had minimal cash income. Significantly fewer of the children with kwashiorkor had been breast-fed or adequately immunised, and 60% had previously been hospitalised for dehydrating diarrhoea. This study demonstrates that in an urban environment the traditional factors of large families and displacement by a younger sibling are not associated with kwashiorkor.(ABSTRACT TRUNCATED AT 250 WORDS)

Red blood cell antioxidant enzyme concentrations in kwashiorkor and marasmus.

Kwashiorkor may occur when an imbalance between pro- and antioxidants in malnourished children results in an excess of free radicals. The concentrations of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH) and glutathione peroxidase (GPX) were measured in erythrocytes of 22 children with kwashiorkor on admission to hospital and repeated on days 5, 10 and 30 of recovery. The concentrations were compared with those in 22 children with marasmus and in 20 children who were normally nourished but had infective illness necessitating their hospitalization. CAT and SOD were similar in all groups and did not change during recovery. GSH and GPX were significantly lower in kwashiorkor than in the other groups. Concentrations of thiobarbituric acid-reactive substances (TBARS), a marker of lipid peroxidation, were significantly elevated in children with kwashiorkor. During clinical recovery, GSH but not GPX concentrations rose despite an increase in plasma selenium levels and decreased concentrations of TBARS. These findings suggest that the antioxidant status of children with kwashiorkor differs from that of well nourished and marasmic children. Whether these differences are the cause of the consequence of the clinical picture is unresolved.

Reversible cerebral shrinkage in kwashiorkor: an MRI study.

Protein energy malnutrition is associated with cerebral atrophy which may be detrimental to intellectual development. The aim of this study was to document the anatomical abnormalities which lead to the appearance of cerebral atrophy using magnetic resonance imaging (MRI) in the acute stage of kwashiorkor and to monitor changes during nutritional rehabilitation. Twelve children aged 6 to 37 months requiring admission to hospital for the treatment of kwashiorkor were studied. The children were evaluated clinically, biochemically, and by MRI of their brains on admission and 30 and 90 days later. Brain shrinkage was present in every child on admission. White and grey matter appeared equally affected and the myelination was normal for age. At 90 days, the cerebral changes had resolved in nine and improved substantially in the remainder, by which time serum proteins and weight for age were within the normal range. The findings of this study suggest that brain shrinkage associated with kwashiorkor reverses rapidly with nutritional rehabilitation.

Plasma zinc, copper, selenium, ferritin and whole blood manganese concentrations in children with kwashiorkor in the acute stage and during refeeding.

Plasma zinc, copper, selenium, ferritin and whole blood manganese concentrations were measured in 22 children with kwashiorkor on admission to hospital and on days 5, 10 and 30 of refeeding. Twenty similarly aged, healthy, well nourished children served as controls. The mean (SEM) zinc, copper and selenium concentrations of 7.5 (0.93), 10.8 (0.64) and 0.29 (0.02) mumol/l, respectively, in the children with kwashiorkor on admission were all significantly lower than the values of 13.7 (0.66), 25.6 (1.72) and 0.72 (0.04) mumol/l in the controls. In contrast, the erythrocyte manganese level of 1.67 (0.09) micrograms/gHb and the median ferritin concentration of 293 micrograms/dl were significantly higher than in the controls. After 30 days there was full clinical recovery with significant weight gain and a return of the plasma albumin, caeruloplasmin, copper and ferritin to normal. However, manganese remained elevated and zinc and selenium concentrations remained significantly low. Our results suggest that nutritional rehabilitation of children with kwashiorkor is incomplete by 30 days and cannot be judged purely by a return of the plasma proteins to normal. Addition of selected trace elements to the diet may hasten full recovery.