Biomedical subjects
Publications and source records attributed to R J Roorda.
We describe a newborn infant with Streptococcus sanguis septicaemia and concomitant upper airway obstruction due to epiglottitis and pharyngitis. This rare infection of the supraglottic region was treated with endotracheal intubation and antibiotics. Full recovery occurred within 4 days.
The outcome of childhood asthma was studied in a cohort of 406 asthmatic children, with emphasis on the influence of family history for allergic disease, as well as the influence of associated allergic diseases on prognosis. Sixty-two per cent had a positive family history for atopy. In young adulthood no differences, either in symptoms or lung function were demonstrated in comparison to subjects with a negative family history. Fifty-two per cent of the children had no other allergic disease, 48% had either eczema or hay fever or both. When subjects were stratified based on associated allergic disease, no differences in outcome in adulthood were revealed either. It is concluded that neither a positive family history, nor concurrent associated allergic diseases in the child contribute to the prognosis of asthma from childhood to young adulthood. Therefore, environmental factors as well as patient characteristics (including lung function level, level of bronchial responsiveness) are likely to be more important for the prognosis.
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Tachyphylaxis to histamine was investigated in 16 children, aged 7-15 years, with mild asthma. Three consecutive histamine challenges were performed at intervals of 24 hours and 1 hour, respectively. No significant differences in IVC, FEV1, and PC20-histamine values between the three measurements were observed. After a 24 hour interval there was no difference in percentage fall of FEV1, but there was a slight (not significant) decrease in fall of FEV1 after a 1 hour interval. The PC20-histamine values showed good reproducibility with a 24 hour as well as with a 1-hour period between the tests (geometric mean PC20, 2.04 mg/mL +/- 3.50 %SD, 1.96 mg/mL +/- 4.37 %SD, 2.17 mg/mL +/- 4.12 %SD; correlation coefficients for a 24 hour interval, r = 0.87 and for a one-hour interval, r = 0.94 (P less than 0.01]. We conclude that in children there is no strong evidence for tachyphylaxis to histamine. Our results differ from studies on tachyphylaxis in adult asthmatics. Possibly different mechanisms exist in children and in adults.
We describe the observation of a 12 yr old girl who died of pulmonary veno-occlusive disease (PVOD). Diagnosis was based on histological examination of an open lung biopsy. The differential diagnosis, pathogenesis and possible therapies are discussed. Although medical therapy can sometimes give some temporary relief, lung transplantation might offer these patients a better chance of survival and a better quality of life.
Bronchial hyperreactivity, the abnormal reaction of the airways on non-allergic stimuli, is a feature of patients with chronic nonspecific lung disease. Several underlying mechanisms such as the neurogenic pathways, inflammatory cells and mediators, increased vascular leakage, epithelial damage and pathological changes in airway smooth muscle seem to play a role of importance in bronchial hyperreactivity. Recent developments in these research fields produce more clarity in the mutual connection of these factors in relation to the phenomenon of bronchial hyperreactivity.
During autumn- and winter epidemics respiratory syncytial (RS) virus accounts for the majority of respiratory infections in infants and young children. In case of an acute lower respiratory tract infection, RS virus can induce serious symptoms. These are age-dependent. The most important symptoms in babies and toddlers are dyspnea, wheezing, cyanosis and apneas. In the case of respiratory insufficiency or fatigue, as well as recurrent apneas, mechanical ventilation is required. Diagnosis can be made using a direct immunofluorescence technique with monoclonal antibodies. To control the risk of nosocomial RS virus infections, isolation precautions are necessary. The overall mortality is low (less than 1%), but may be strikingly higher in children at risk: babies less than one month of age, preterm babies, infants with congenital heart- or pre-existent respiratory diseases, and those with severe immunodeficiency syndromes. In these subgroups therapy with ribavirin (Virazole) may be beneficial, although until now there is no strong evidence for the effectiveness of this antiviral agent. The majority of the children will have recurrent symptoms of dyspnea and wheezing over the subsequent years following the RS virus infection. In acute lower respiratory RS virus infection, there may be IgE mediated hypersensitivity reactions to viral agents, with release of chemical mediators of airway obstruction. The pathophysiological mechanisms might be comparable to those in patients with asthma.
Nocturnal airflow obstruction is a common symptom in children with asthma. The increase in airflow obstruction overnight is underassessed by children as well as their parents. Worsening of the early morning peak flow values may be an indication for an increase in airflow obstruction overnight. An increase in vagal activity does not, in contrast with the observations in adult patients, contribute to the development of nocturnal airflow obstruction in asthmatic children. However, a nocturnal increase in inflammatory mediators seems to play a role of importance. Treatment of nocturnal airflow obstruction should therefore be focussed on inflammatory processes in the lungs.
In approximately 50 per cent of the children with asthma respiratory symptoms, these symptoms disappear during puberty. Outgrowing childhood asthma is especially estimated by: the degree of airway obstruction as a child, and the degree of bronchial hyperreactivity in childhood. Another childhood factor of influence on the prognosis of asthma seems to be the combined early and late bronchial response after inhalation of an allergen. Factors not predicting the outcome of childhood asthma are: at what age asthma symptoms started; whether the child with asthma had eczema or not, and how strong skin-allergy was. Conceivable risk-factors for the outcome of childhood asthma are: smoking of the parents and a strong degree of eosinophilia. The prognosis of asthma might be improved by more intensive treatment and continuity in treatment of the children with an increased risk.
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We describe two children with congenital deformities due to the early amniotic rupture syndrome. One child who had an amniotic band around the upper arm suffered from a distal nerve lesion. This was relieved following surgery. The second child died shortly after birth of multiple congenital malformations. The most usual findings in this syndrome are constriction of a limb by an amniotic band, scoliosis or syndactyly due to oligohydramnion with compression. We discuss one accepted hypothesis (subscribed by an experimental animal study) of the aetiology of the early amniotic rupture syndrome.
Forced oscillometry was used to investigate whether lung injury due to bronchopulmonary dysplasia in early life caused abnormalities in bronchial calibre or an increase in bronchial responsiveness to histamine at school age. Results were compared with data obtained from healthy children born prematurely and from healthy children born at term. There was a mild increase in frequency dependence of total respiratory resistance in children who suffered from lung injury in early life, which indicates uneven ventilation in peripheral airways. Bronchial responsiveness to histamine in these subjects was normal. No abnormalities were found in the control group. We conclude that lung injury in early life may cause residual abnormalities of peripheral airways. This does not happen in premature babies who do not have respiratory problems in the neonatal period.