Search PubMed⌕ Search

Biomedical subjects

D M Roberton

Publications and source records attributed to D M Roberton.

At least 37 records · Page 2Linked to original sources

Adverse outcomes of bacterial meningitis in school-age survivors.

OBJECTIVE: To determine the outcomes of bacterial meningitis in school-age survivors. DESIGN: Prospective cohort study. SETTING: Teaching pediatric hospital. CHILDREN: During 1983 through 1986, 158 meningitis survivors, ages 3 months to 14 years, treated at a single center were enrolled. Between 1991 and 1993, 130 children, 82% of the original cohort, were evaluated at a mean age of 8.4 years and a mean of 6.7 years after their meningitis. OUTCOME MEASURES: Blinded neurologic, neuropsychologic, audiologic, behavior, and socio-demographic assessments were compared with those from grade- and sex-matched control children. Multivariate analyses adjusted for age at testing and socio-demographic variables. RESULTS: There was a systematic increase in risk of abnormality or poorer functioning for children with meningitis, compared with control children, across all categories tested, which was significant for fine motor function, Intelligence quotient (IQ) scores, and tests of school behavior, neuropsychologic function, and auditory figure-ground differentiation. Eleven children who had experienced meningitis (8.5%) had major deficits (IQ < 70, seizures, hydrocephalus, spasticity, blindness, or severe to profound hearing loss); a further 24 (18.5%) cases and 14 (10.8%) control children had minor deficits (IQ 70 to 80, inability to read, mild to moderate hearing loss, abnormalities in speech discrimination, or school behavior problems). Overall, children who had meningitis were at greater risk (26.9%) for disability. Children with acute neurologic complications had more adverse outcomes than those with uncomplicated meningitis and control children (39% vs 18% vs 11%, respectively). CONCLUSIONS: One in four school-age meningitis survivors has either serious and disabling sequelae or a functionally important behavior disorder, neuropsychologic or auditory dysfunction adversely affecting academic performance. As a group, survivors function less well than their classroom peers, and risk is greatest for, but not confined to, those who had acute neurologic complications. All survivors require careful follow-up, at least until school age.

Adolescent↗

Atlantoaxial subluxation in children with seronegative enthesopathy and arthropathy syndrome: 2 case reports and a review of the literature.

We describe 2 HLA-B27 positive children with seronegative enthesopathy and arthropathy (SEA) syndrome who developed spontaneous (nontraumatic) atlantoaxial subluxation early in their disease course. Neither child had evidence of spinal cord compression but both had progressive atlantoaxial subluxation in spite of conservative treatment. Both underwent elective posterior cervical (C1-C2) fusion.

Adolescent↗

Immune activation during infancy in healthy humans.

Immune activity during infancy was investigated using blood samples from 30 neonates and 52 healthy infants between 2 and 15 months of age attending for immunization. The purpose of this study was to assess the total immune activity of T cells using soluble interleukin-2 receptor (IL-2R) and interferon-gamma concentrations. These were compared with the proportion of CD4 CD45RO-, IL-2R (CD25)-, and transferrin receptor (CD71)-positive peripheral blood lymphocytes. The median duration of breast-feeding and of introduction of solid feeds was 4.2 and 4.0 months, respectively. Compared to neonates, the mean +/- SE soluble IL-2R concentration peaked at 4 months of age (1670 +/- 94 vs 3060 +/- 252 U/ml; P < 0.0001), as did pooled interferon-gamma levels. The percentage of CD4 CD45RO T cells remained low and the proportion of activated peripheral blood lymphocytes decreased during infancy. We conclude that noncirculatory immune activity is increased during infancy and this is associated with weaning.

Antigens, CD↗

Phenotype of T cells, their soluble receptor levels, and cytokine profile of human breast milk.

Human breast milk has important immunoprotective and immunosuppressive functions for an infant. The purpose of this study was to extend the phenotype of milk cells and to measure soluble T cell receptor levels and cytokines in milk, and to compare these with neonatal and adult blood. Milk T cells had a more equivalent CD4:CD8 ratio than blood; milk CD4 T cells mainly expressed the CD45RO (antigen primed/memory) phenotype; milk CD8 cells had an equivalent CD11b:CD28 suppressor:cytotoxic phenotype; and milk T cells had 2-3-fold higher percentages of activated CD4 IL-2R and CD8 HML-1 or CD8 VLA-1 cells than blood. Soluble IL-2R, CD4 and CD8 concentrations were lower in milk than adult blood, although relatively increased when compared to the lower T cell concentration in milk. Breast milk contained high levels of IFN-gamma but low levels of other measured cytokines compared to blood. These distinct differences of T cells and their soluble products are likely to influence an infant's immune system.

Adult↗

Reiter's syndrome in an adolescent girl.

This report describes a 14-year-old girl who presented with an Escherichia coli urinary tract infection followed by diarrhoea, arthritis and iritis. She had continuing symptoms intermittently for six months, but was HLA-B27 antigen negative. The occurrence of Reiter's syndrome is unusual in young females and we are not aware of any reports of reactive arthritis following E. coli urinary tract infection in children.

Adolescent↗

Lymphocyte production of gamma-interferon as a test for non-tuberculous mycobacterial lymphadenitis in childhood.

Infection with Mycobacterium avium, M. intracellulare and M. scrofulaceum (MAIS) organisms in normal children may result in cervical lymphadenopathy. There is a poor response to anti-tuberculous therapy and surgical excision of infected nodes is necessary. The diagnosis therefore requires consideration in children with cervical lymphadenopathy. A simple in vitro assay is described which may be useful for diagnosis prior to excision. Whole blood is cultured with M. avium purified protein derivative. After 24 h the plasma is removed and the concentration of gamma interferon (IFN-gamma) quantified by a radioimmunometric assay. In a prospective study of 38 children with neck lesions, 16 showed MAIS organisms isolated from cultures of excised tissue. The level of IFN-gamma produced by peripheral blood lymphocytes from children in the MAIS group was significantly greater when compared with children having operations for neck lesions that were not due to MAIS organisms (P < 0.001).

Adolescent↗

Chronic multifocal osteomyelitis.

We describe 22 patients who presented between the ages of 4 and 14 years with gradual onset of malaise and pain at the sites of multiple bone lesions. The symptoms from the bone lesions were sometimes sequential in onset and often relapsing. The radiological findings were typical of osteomyelitis. Radioisotope bone scans identified some clinically silent lesions. Bone biopsies were performed in 20 patients and the changes of osteomyelitis were seen in 17; microbiological culture was positive in only one. Seven patients had polyarthritis, two had palmoplantar pustulosis and one had psoriasis. Some symptomatic relief was obtained with anti-inflammatory agents and, to a less extent, with antibiotics. No patient had primary immunodeficiency. The mean duration of symptoms from the bone lesions was two years (1 to 4). When arthritis was present the joint symptoms lasted considerably longer (mean 7 years; range 4 to 10). The long-term prognosis was generally good. There was no evidence of altered bone growth or abnormal joint development. One patient developed a progressive kyphosis requiring fusion, but no other surgical intervention was necessary.

Adolescent↗

Bovine milk, including pasteurised milk, contains antibodies directed against allergens of clinical importance to man.

Pasteurised and raw bovine milk and bovine colostrum samples were assayed by enzyme-linked immunoassay for the presence of antibodies directed against a selection of allergens of importance in human atopic disease. Samples were tested for the presence of antibodies directed against or cross-reacting with ryegrass pollen, house dust mites, Aspergillus mould and wheat proteins. Antibodies of each specificity were detected in every sample tested, including all samples of commercial pasteurised milk. The results are discussed with reference to a hypothesis that dietary xenogeneic antibodies may play a role in the emergence of some human atopic disease, and the recent demonstration that oral immunisation with xenogeneic antibodies may lead to the production of anti-immunoglobulin antibodies including anti-idiotypic antibodies.

Allergens↗

Oral immunization with xenogeneic antibodies stimulates the production of systemic and mucosal anti-idiotypic antibodies.

The humoral and mucosal immune responses to oral immunization with xenogeneic antibodies were studied using an animal model in which female rabbits were fed daily doses of the MOPC-315 murine IgA antibody, and were mated during the course of the feeding programme. Serum and colostrum samples were assayed for the presence of anti-idiotypic antibodies by ELISA assay, before and after depletion of anti-IgA antibodies, by affinity chromatography using another murine IgA idiotype. It was shown that all animals responded to exposure to the MOPC-315 idiotype with the production of serum anti-murine immunoglobulin antibodies and that four of six animals produced serum anti-idiotypic antibodies. That the immune response included antibodies directed against the antigen-binding site was confirmed by competition ELISA assay. Mucosal IgG and IgA anti-immunoglobulin antibodies were present in milk from all antibody-fed rabbits tested, and IgA anti-idiotypic antibodies were detectable in the colostrum of one rabbit. The results provide some support for the hypothesis that human exposure to xenogeneic antibodies, most commonly bovine milk immunoglobulins, may provoke the production of anti-idiotypic antibodies, and that such exposure may lead to disturbances of immune regulation.

Administration, Oral↗

Polymeric IgA and immune complex concentrations in IgA-related renal disease.

Polymeric IgA (PIgA) and immune complex concentrations in IgA-related renal disease were measured in cross sectional and longitudinal studies to establish the relationship between these parameters and both mucosal infection and renal dysfunction. These studies were performed in 50 patients with IgA nephropathy (IgAN), 17 patients with Henoch Schönlein purpura nephritis (HSPN), 11 control patients with IgA negative, diffuse mesangial proliferative glomerulonephritis (DMPGN) and 50 healthy controls. Total PIgA (PIgAT) and PIgA subclass concentrations were measured using a secretory component binding enzyme immunoassay and isotype specific immune complex concentrations were measured using conglutinin (K) binding immunoassays. In cross sectional studies patients with IgAN were found to have increased concentrations of PIgAT, PIgA1, K-IgA1 and K-IgA2 compared to controls. In the longitudinal studies controls and patients had significant increases in PIgAT and PIgA1 concentrations during infection. However, in patients with IgAN, the increases were greater, persisted for longer, and PIgA2 concentrations were also increased. K-IgA1 and K-IgA2 concentrations increased significantly during episodes of infection in IgAN patients in contrast to controls. Patients with HSPN had results similar to those of IgAN patients. No significant correlation was found between PIgA or K-IgA concentrations, and either serum creatinine concentrations or the degree of hematuria. The results indicate that patients with IgA-related renal disease have abnormal regulation of PIgA and immune complexed IgA, and that these abnormalities are exaggerated during mucosal infection.

Adolescent↗

Immunoglobulin and anti-Escherichia coli antibody in lower respiratory tract secretions from infants weighing less than 1500 g at birth.

Concentrations of immunoglobulins and anti-Escherichia coli antibody were studied longitudinally in tracheobronchial aspirates from 33 premature intubated neonates, median gestational age 27 weeks. Aspirates collected at birth contained IgG, IgA, and IgM in 100%, 93%, and 79% of samples, respectively. The median IgA concentration at birth was 0.7 micrograms/mg total protein and increased to 5.8 micrograms/mg protein by the sixth week. IgG and IgM antibodies to E coli were present in 90% and 30%, respectively, of tracheobronchial aspirates collected at birth. Samples from three of 28 neonates (11%) contained IgA anti-E coli antibody at birth, and the proportion with IgA antibody rose to 50% during the sixth week. Secretory component associated IgA and IgM were detectable in samples tested at birth and at 4 weeks of age, and secretory component associated anti-E coli antibody was present in aspirates from three of nine neonates studied at 4 weeks of age, but had not been detectable at birth.

Antibodies, Bacterial↗

Markers of serious illness in infants under 6 months old presenting to a children's hospital.

Six hundred and eighty two assessments were performed on 641 babies under 6 months of age who presented to the emergency department of the Royal Children's Hospital, Melbourne, to try and determine the best markers of serious illness in young infants. Detailed, specific questions that quantified a baby's functional response to illness gave the most useful information. As a group, the six most common predictive symptoms of serious illness were: taking less than half the normal amount of feed over the preceding 24 hours, breathing difficulty, having less than four wet nappies in the preceding 24 hours, decreased activity, drowsiness, and a history of being both pale and hot. The presence of the corresponding sign on examination increased the predictive value of the symptom by 10-20%. Specific, highly predictive (though less common) signs included moderate to severe chest wall recession, respiratory grunt, cold calves, and a tender abdomen. A list of low, medium, and high risk symptoms has been constructed and the five measurements that were most useful in predicting serious illness in young infants have been detailed.

Causality↗

Maternofetal transfer of IgG anti-Escherichia coli antibodies with enhanced avidity and opsonic activity in very premature neonates.

Total IgG concentrations, IgG antibody concentrations to pooled Escherichia coli antigens, and IgG anti-E. coli antibody avidity were measured in cord and maternal serum samples collected from 52 mother-infant pairs after premature delivery (mean gestational age 28 wk, range 23-33 wk). The mean IgG anti-E. coli antibody concentration in cord serum (1.86 relative units/mL) was markedly lower than in maternal serum (5.42 relative units/mL) at this gestation (p less than 0.0001). Cord serum IgG anti-E. coli antibody concentrations correlated closely with maternal IgG anti-E. coli concentrations when controlled for the effect of gestational age (partial correlation coefficient 0.89; p less than 0.001) but only weakly with gestational age when controlled for maternal IgG antibody concentrations (partial correlation coefficient 0.23; p = 0.06). The mean ratio of cord to maternal IgG anti-E. coli antibody concentrations was considerably lower than the mean ratio for total IgG concentrations (0.34 versus 0.72; p less than 0.001). The mean avidity of IgG antibody for the pooled E. coli antigens was significantly greater in cord serum than in maternal serum (2.45 versus 1.99M; p less than 0.0001). There was a close correlation between cord and maternal antibody avidity (r = 0.70; p less than 0.001), but cord IgG antibody avidity did not correlate with gestational age (r = -0.07; p = 0.61), nor with cord IgG anti-E. coli antibody concentrations (r = 0.10; p = 0.50).(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Bacterial↗

IgG subclass concentrations in absolute, partial and transient IgA deficiency in childhood.

Sixty-seven children with symptomatic IgA deficiency were studied on two separate occasions. Eighteen had aIgAd at presentation, and 49 had pIgAd. IgA concentrations had risen to the normal range for age in 22.2% of children presenting with aIgAd and 77.6% presenting with pIgAd when restudied at a median interval of 3.2 and 3.0 years, respectively. IgG subclass concentrations were measured by enzyme immunoassay in serum samples collected at enrollment from 12 children with aIgAd and 22 children with pIgAd. IgG2 and IgG4 concentrations for these 34 children were below the 5th centile for age and sex more frequently than expected (IgG2: chi square 5.8, P less than 0.025; IgG 4: chi square 18.4, P less than 0.0005). The prevalence of IgG2 deficiency or IgG4 deficiency did not differ significantly between those with aIgAd and those with pIgAd. IgG2 concentrations remained below the 5th centile more frequently than expected when retested in 31 children whose pIgAd had resolved (chi square 4.6, P less than 0.05). Children with aIgAd at presentation had IgG1 and IgG2 concentrations above the 95th centile more frequently than expected (IgG1: chi square 19.7, P less than 0.0005; IgG2: chi square 13.5, P less than 0.001) but this was not seen for IgG3 and IgG4 concentrations. Children with pIgAd did not have elevated IgG1 or IgG2 concentrations at presentation. High IgG1 and IgG2 concentrations in aIgAd may be a compensatory mechanism to afford protection from infection or could be part of a selective secondary response to repeated episodes of infection.

Adolescent↗

Non-tuberculous mycobacterial lymphadenitis in children.

Eighty-six children (44 males, 42 females) were identified as having non-tuberculous mycobacterial lymphadenitis. The diagnostic criteria were either culture of the organism from the affected lymph node (n = 68), or, when culture was negative, a positive skin test with non-tuberculous mycobacterial antigens and negative skin test responses to tuberculin purified protein derivative (PPD) in association with typical histological features (n = 18). All children had histopathological findings of granulomatous inflammation with caseation and/or acid-fast bacilli. Eighty-two percent of the children were under 5 years of age at presentation and 30% were less than 2 years old. Most (79%) were city dwellers. Lymph node enlargement had been present for less than 6 months in almost all children (97.5%) and was almost exclusively in the face and neck region (97%). Disease was confined to the involved lymph nodes in 56% but had extended beyond the confines of the infected node to form a collar stud abscess in 38% and 6% presented with a skin sinus. Extranodal extension did not show any statistically significant association with the duration of lymphadenopathy. The duration of lymphadenopathy had been greater in those children in whom an organism was not isolated on culture resected tissue (chi 2 = 10.07, P less than 0.01). All children were treated surgically, and recurrence occurred in five patients. This study describes the clinical and demographic characteristics of non-tuberculous mycobacterial lymphadenopathy in children in a population in which tuberculous adenitis is rare. Recognition of these features may allow earlier diagnosis and appropriate surgical therapy.

Child↗