Cellular profiles of induced sputum in children with stable cystic fibrosis: comparison with BAL.

Neutrophil-dominated endobronchial inflammation is a major characteristic of cystic fibrosis (CF) and there is increasing demand for easy-to-perform noninvasive monitoring for prediction and intervention. Fourteen stable paediatric CF patients (8-17 yrs; mean forced expiratory volume in one second 86.7% of the predicted value) were investigated once by fractional bronchoalveolar lavage (BAL) and by sputum induction on three occasions, 2-6 weeks apart. Sputum was induced by consecutive 10-min inhalations of 3, 4 and 5% saline. CF sputum cellular profiles were compared with BAL fluid cell counts and samples from age-matched healthy children, and between different time points to assess reproducibility. Adequate sputum was recovered on >95% of occasions. In all sputum fractions, CF patients showed higher neutrophil counts than healthy children. Neutrophil percentages were highest in the first BAL fraction (median 92%), followed by sputum, in which the percentages decreased in consecutive fractions (72, 66 and 64%), whereas counts were lowest in the pooled BAL fraction (53%). Increasing percentages of macrophages mirrored the decreases in neutrophil percentage. Results of sputum induction at different time points in the CF patients showed good reproducibility and nonoverlap with counts from healthy children. In conclusion, the results of sputum induction in children with mild stable cystic fibrosis adequately describe airway inflammation by providing cellular profiles with lower relative neutrophil counts than in the first ("bronchial") bronchoalveolar lavage fraction and higher relative neutrophil counts than in subsequent pooled ("more peripheral") bronchoalveolar lavage fractions.

Sequential genotyping of Pseudomonas aeruginosa from upper and lower airways of cystic fibrosis patients.

A controversy exists concerning the adequate specimen to characterise colonisation of cystic fibrosis (CF) airways by Pseudomonas aeruginosa. Oropharyngeal, sputum and bronchoalveolar lavage samples were evaluated from 38 stable CF patients for the detection of P. aeruginosa, genetically different isolates within the same host and longitudinal variations in the genotype during repeated examinations. Bacterial isolates were typed by pulsed-field gel electrophoresis of deoxyribonucleic acid macrorestriction fragments. Sensitivity, negative and positive predictive values and specificity to detect P. aeruginosa were 35.7, 73.5, 83.3 and 96.2% for oropharyngeal cultures in nonexpectorating patients and 91.7, 94.1, 100 and 100% for sputum cultures from expectorating patients, respectively. Genotypes of Pseudomonas isolates recovered from oropharyngeal swabs and sputum differed to the strains recovered by bronchoscopy in 55% and 40%, respectively. In 62% longitudinal variations in the genotype occurred. One-half of these alterations were detectable by bronchoscopy only. In conclusion, sputum samples were of equal value as specimens from bronchoalveolar lavage to detect Pseudomonas aeruginosa colonisation. Cultures from the oropharynx are not suitable for characterising bacterial conditions in the cystic fibrosis lung. Different genotypes within the same host and longitudinal genetic alterations are common and may be detectable in the bronchoalveolar lavage fluid exclusively.

Fractional analysis of bronchoalveolar lavage fluid cytology in cystic fibrosis patients with normal lung function. Bronchoalveolar lavage for the evaluation of anti-inflammatory treatment (BEAT) study group.

Cystic fibrosis (CF) is associated with a neutrophil dominated airway inflammation. So far bronchoalveolar lavage (BAL) studies in CF have used pooled BAL samples which may be more representative of the alveolar compartment rather than the airways. To assess whether the first sample of a BAL is more sensitive in the evaluation of airway inflammation, the authors have studied 105 stable CF patients aged 5-37 yrs with a mean forced expiratory volume in one second (FEV1) of 96+/-15% (mean+/-SD). BAL cytology of the first and pooled samples were compared to reference values obtained in children without respiratory disease. Absolute cell counts and the percentage of neutrophils were significantly increased in CF patients. If the 95% confidence interval was used as a cut-off point, 17/105 CF patients had a normal percentage of neutrophils in pooled BAL samples, but only three also had a normal percentage of neutrophils in the first BAL aliquot. Therefore, neutrophil dominated airway inflammation is more pronounced in the first, mainly bronchial, bronchoalveolar lavage sample suggesting that sequential analysis of bronchoalveolar lavage fluid may have a higher sensitivity to detect early inflammatory changes in CF patients.

Increasing dose of methylprednisolone pulse therapy treats desquamative interstitial pneumonia in a child.

A 10 yr old male with hypoxaemia, progressive infiltration on the chest radiograph and biopsy-proven desquamative interstitial pneumonia was treated with daily oral prednisolone for 6 months. Intravenous methylprednisolone pulses were concomitantly administered in doses averaging 10 mg x kg body weight(-1) on three consecutive days every 4-6 weeks. After 6 months improvement could be noted and oral steroids were stopped, while pulse therapy continued. Three months later, when seven pulses had been administered, a relapse occurred and the clinical status deteriorated. Instead of reinstating daily systemic steroids, the dose of methylprednisolone pulses was increased to 20 mg x kg body weight(-1) i.v. given on three consecutive days and repeat pulses every 4 weeks. This was followed by continuous improvement. After 24 months corticosteroid pulses were terminated. Normal lung function, serum lactate dehydrogenase, blood gases upon exertion and regular development was achieved. During the course of treatment, the child has grown 10 cm. It is concluded that the effect of corticosteroid pulse therapy on interstitial lung disease in childhood is dose-dependent and that the dose can be adjusted to the effect observed.

Bronchiolitis obliterans organizing pneumonia and chronic graft-versus-host disease in a child after allogeneic bone marrow transplantation.

We report an 8-year-old boy who developed cough and respiratory failure 7 months after bone marrow transplantation (BMT) coinciding with the onset of chronic graft-versus-host disease (GVHD). Lung function data, imaging studies, lung biopsy and bronchoalveolar lavage were consistent with the diagnosis of bronchiolitis obliterans organizing pneumonia. While this has been reported in association with chronic graft-versus-host disease in one adult case previously, we report the simultaneous occurrence of BOOP and chronic GVHD in a child after bone marrow transplantation for the first time.

Individual time-courses of ECP and EPX during allergen provocation tests in asthmatic children.

To study the time-course of eosinophil cationic protein (ECP) and eosinophil protein X (EPX) during bronchial allergen provocation, we investigated 32 asthmatic children sensitive to house-dust mites as well as 6 non-atopic young adult controls. In all subjects, allergen challenges were performed with house dust mite extracts of Dermatophagoides pteronys-sinus or Dermatophagoides farinae. Blood samples were taken at regular intervals during the 24-h observation period. The individual time-courses of ECP and EPX revealed different characteristic groups of patterns: (1) an isolated early serum peak of both mediators during or within the first 60 min after provocation (2) an early plus a late peak (3) an isolated late peak 12 h after provocation (4) an isolated late peak 24 h after provocation, and (5) no significant variation during the 24-h observation period. The early peak could be due to short-term changes in eosinophil activation, while late peaks may reflect eosinophil proliferation, recruitment, subsequent priming and enhancing of the propensity to release their proteins. ECP and EPX showed a corresponding parallel time-course in nearly all challenges, with EPX-concentration exceeding that of ECP. There was no correlation between ECP/EPX serum concentrations and clinical parameters such as lung function data. From our results we conclude that the striking groups of time-courses of ECP/EPX serum concentration indicate different uniform patterns of eosinophil activation during allergen challenge-but do not predict clinical outcome of provocation. The role of the eosinophil in early asthmatic reactions remains to be established in further studies.

Discrepancies between in vitro and in vivo tests for house dust mite allergy: in domestic exposure a better predictor than sensitization?

We subjected seven asthmatic children to two bronchial allergen challenges, first with an extract from the house dust mite Dermatophagoides pteronyssinus (Der p) and then Dermatophagoides farinae (Der f), or vice versa. All children had elevated specific serum IgE to both species as well as reactions by crossed radioimmuno/electrophoresis (CRIE) to both group I and II allergens from both species. Immunoabsorption and subsequent analysis by CRIE showed a considerable concentration of serum IgE with specificity for epitopes common to the two species of house dust mite. Home dust sampling established that all children were exposed to Der f and only two to Der p. On bronchial provocation tests, all responded to Der f with an immediate reaction and five with a late reaction, only three of seven showed an immediate response to Der p, with four of the seven showing a late reaction. Our data could indicate that the local allergic immune reaction in the respiratory tract is sustained by ongoing exposure, and may thus have a different species specificity than the response reflected in the serum. In conclusion, our data indicates a lack of association between in vitro and in vivo tests for house dust mite allergy, which supports the continuing need for monitoring current clinical sensitization by allergen provocation tests and by measuring domestic exposure to the corresponding allergen. Extended studies are needed to support our findings.

Twenty-four-hour time course of eosinophil granule proteins ECP and EPX during bronchial allergen challenges in serum of asthmatic children.

To study in vivo monitoring variables for bronchial allergen challenges, we investigated the time course of the eosinophil granule proteins, eosinophil cationic protein (ECP) and eosinophil protein X (EPX) after allergen provocation in serum. Thirty-two asthmatic children sensitive to house-dust mites and six healthy young adult controls were challenged by bronchial allergen provocations with Dermatophagoides pteronyssinus and D. farinae. Blood samples were taken at regular intervals up to 24 h. Base-line concentrations of ECP (P < 0.004), EPX (P < 0.002), and eosinophils (P < 0.001) were found to be increased in asthmatic children, as compared with healthy controls. ECP and EPX concentrations showed a uniform pattern with two characteristic features: 1) a rapid increase for both mediators up to 30 min after provocation over base-line values (P < 0.0001 and P < 0.001), followed by a rapid decrease nearly to base-line values in the next 30 min; and 2) a steady increase for ECP and EPX up to 10 h (P < 0.02 and P < 0.01), and even higher levels at 24 h, after challenge (P < 0.002 and P < 0.003). We conclude that although eosinophils are activated in asthmatic children after bronchial allergen challenge, ECP and EPX concentrations are not suitable monitoring variables. Base-line eosinophils seem to predict the occurrence of a late-phase asthmatic reaction after allergen provocation.

Lymphocyte subsets, sIL2-R and sICAM-1 in blood during allergen challenge tests in asthmatic children.

In order to study cell activation in peripheral blood on bronchial allergen provocation up to 24 h, we investigated 32 asthmatic children, sensitive to house-dust mites. Six healthy young adult volunteers served as controls. Lymphocyte subsets (CD3, CD19, CD4, CD8) and activation markers (CD25-T, HLADR-T, CD23) in peripheral blood as well as soluble IL2-R and soluble ICAM-1 in serum were evaluated. In terms of clinical reaction, 23 children exhibited a DAR, 6 an EAR, 6 a LAR and 3 children did not show a bronchoconstrictor response to allergen challenge with house-dust mite extract (NAR). In comparison to controls, asthmatic children showed a significantly higher expression of CD23 on B-lymphocytes (p < 0.05). Other subsets were in the same range in both groups. After provocation there was a significant increase of CD4/CD8-ratio only in asthmatic children. Serum levels of sIL2-R were significantly higher in asthmatic children compared to controls at baseline as well as at 12 and 24 h after provocation, without variation during observation period. No differences were noted for sICAM-1. Our results confirm the hypothesis that lymphocytes, as important cells in regulation of allergic immune response, are recruited into peripheral blood under allergen challenge conditions in sensitized asthmatic children.

Monitoring of inflammation during challenge tests in children.

From our data we conclude, that the determinations of ECP and EPX do not add any useful information as monitoring parameters for bronchial allergen challenge tests. In contrast, eosinophils and eosinophil cationic protein may deserve further study as potentially useful monitoring parameters for oral food challenges in patients with food related atopic eczema.