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K De Boeck

Publications and source records attributed to K De Boeck.

At least 19 recordsLinked to original sources
PubMed2006

Survey of Pseudomonas aeruginosa genotypes in colonised cystic fibrosis patients.

The current authors aimed to examine whether cystic fibrosis (CF) patients in Belgium shared Pseudomonas aeruginosa genotypes and to compare the genotypes of isolates from the same patients during two consecutive years. A Belgian databank of the P. aeruginosa genotypes of all colonised CF patients was created. Sputum samples from a total of 276 P. aeruginosa colonised patients during 2003, and from a subgroup of 95 patients in 2004, were analysed. Patients were asked about any social contact between each other by questionnaire. All P. aeruginosa isolates exhibiting different colonial morphology on McConkey agar were first genotyped using arbitrarily primed PCR, whereafter single representatives of each randomly amplified polymorphic DNA-type were further genotyped by fluorescent amplified fragment length polymorphism analysis. In the 213 patients from whom P. aeruginosa could be cultured (resulting in 910 isolates), a total of 163 genotypes were found. The majority (75%) of patients harboured only one genotype. In most of the limited number of clusters, previous contacts between patients could be suspected. In 80% of the patients studied during both years, P. aeruginosa genotype remained unchanged. In conclusion, most colonised cystic fibrosis patients harbour only one Pseudomonas aeruginosa genotype, despite showing different colonial morphotypes. The number of clusters is limited, and most patients seem to retain the same genotypic strain during both years.

Adolescent↗
PubMed2006

Role of magnesium in the failure of rhDNase therapy in patients with cystic fibrosis.

BACKGROUND: In the management of cystic fibrosis (CF), rhDNase-I inhalation is widely used to facilitate the removal of the highly viscous and elastic mucus (often called sputum) from the lungs. However, an important group of CF patients does not benefit from rhDNase-I treatment. A study was undertaken to elucidate the reason for the failure of rhDNase-I in these patients and to evaluate strategies to overcome this. METHODS: The biochemical properties, physical properties, and degradation by rhDNase-I of sputum obtained from clinical responders and non-responders to rhDNase-I were compared, and the ability of magnesium to reactivate rhDNase-I in DNA solutions and in sputum was investigated. The effect of oral magnesium supplements on magnesium levels in the sputum of patients with CF was also examined. RESULTS: Sputum from clinical responders was extensively degraded in vitro on incubation with rhDNase-I, while sputum from clinical non-responders was not degraded: the median decrease in sputum elasticity in the two groups was 32% and 5%, respectively. Sputum from clinical responders contained significantly higher concentrations of magnesium than sputum from non-responders (2.0 mM v 1.3 mM; p = 0.020). Sputum that could not be degraded by rhDNase-I became degradable after preincubation with magnesium. The effect of magnesium on rhDNase-I activity was mediated through actin. Oral intake of magnesium enhanced the magnesium concentration in the sputum of CF patients. CONCLUSION: Increasing the magnesium concentration in sputum by, for example, oral magnesium supplements may be a promising new strategy to overcome the failure of rhDNase-I in patients with CF.

Administration, Inhalation↗
PubMed2005

Cystic fibrosis: terminology and diagnostic algorithms.

There is great heterogeneity in the clinical manifestations of cystic fibrosis (CF). Some patients may have all the classical manifestations of CF from infancy and have a relatively poor prognosis, while others have much milder or even atypical disease manifestations and still carry mutations on each of the CFTR genes. It is important to distinguish between these categories of patients. The European Diagnostic Working Group proposes the following terminology. Patients are diagnosed with classic or typical CF if they have one or more phenotypic characteristics and a sweat chloride concentration of >60 mmol/l. The vast majority of CF patients fall into this category. Usually one established mutation causing CF can be identified on each CFTR gene. Patients with classic CF can have exocrine pancreatic insufficiency or pancreatic sufficiency. The disease can have a severe course with rapid progression of symptoms or a milder course with very little deterioration over time. Patients with non-classic or atypical CF have a CF phenotype in at least one organ system and a normal (<30 mmol/l) or borderline (30-60 mmol/l) sweat chloride level. In these patients confirmation of the diagnosis of CF requires detection of one disease causing mutation on each CFTR gene or direct quantification of CFTR dysfunction by nasal potential difference measurement. Non-classic CF includes patients with multiorgan or single organ involvement. Most of these patients have exocrine pancreatic sufficiency and milder lung disease. Algorithms for a structured diagnostic process are proposed.

Action Potentials↗
PubMed2005

Association of tumour necrosis factor alpha variants with the CF pulmonary phenotype.

BACKGROUND: The pulmonary phenotype in patients with cystic fibrosis (CF), even in those with the same CF transmembrane conductance regulator (CFTR) genotype, is variable and must therefore be influenced by secondary genetic factors as well as environmental factors. Possible candidate genes that modulate the CF lung phenotype may include proinflammatory cytokines. One such protein is tumour necrosis factor alpha (TNFalpha), a member of the immune system. METHODS: Three polymorphic loci in the promoter (-851c/t, -308g/a, -238g/a) and one polymorphic locus in intron 1 (+691g ins/del) of the TNFalpha gene were typed by a single nucleotide primer extension assay in CF patients and healthy controls. Spirometric data and first age of infection with Pseudomonas aeruginosa were collected retrospectively from patients' medical records. RESULTS: An association was found between the TNFalpha +691g ins/del polymorphic locus and severity of CF lung disease. Patients heterozygous for +691g ins and +691g del were more likely to have better pulmonary function (mean (SD) forced expiratory volume in 1 second (FEV1) 79.7 (12.8)% predicted) than patients homozygous for +691g ins (mean (SD) FEV1 67.5 (23.0)% predicted; p = 0.008, mean difference 12.2%, 95% CI 3.5 to 21.0). Also, patients heterozygous for +691g ins and +691g del were more likely to have an older first age of infection with P aeruginosa (mean (SD) 11.4 (6.0) years) than patients homozygous for +691g ins (mean (SD) 8.3 (4.6) years; p = 0.018, mean difference 3.1 years, 95% CI 0.5 to 5.6). An association was also found with the -851c/t polymorphic locus. In the group of patients with more severe FEV1% predicted, a higher proportion of patients were homozygous for the -851c allele than in the other group of patients (p = 0.04, likelihood ratio chi2, odds ratio = 2.4). CONCLUSION: TNFalpha polymorphisms are associated with the severity of CF lung disease in Czech and Belgian patients with CF.

Adolescent↗
PubMed2005

Mucociliary transport using 99mTc-albumin colloid: a reliable screening test for primary ciliary dyskinesia.

BACKGROUND: A study was undertaken to assess the reliability of the nasal mucociliary transport test using 99mTc-albumin colloid as a screening test for primary ciliary dyskinesia (PCD) and to compare it with the gold standard nasal biopsy for study of ciliary motility and ultrastructure. METHODS: During a 4 year period both tests were performed in 55 children referred with persistent or recurrent respiratory tract infections. Their median age was 4 years (range 1 month to 15 years). RESULTS: The nasal biopsy results were as follows: PCD, n = 8; secondary ciliary dyskinesia (SCD), n = 19; normal, n = 28. The mucociliary transport test was abnormal in 29 patients (all 8 with PCD, 7/19 with SCD, and 14/28 with a normal biopsy). The sensitivity of the mucociliary transport test to diagnose PCD was therefore 100% (8/8) (95% exact confidence limits 63.06 to 100.00); the specificity was only 55% (26/47) (40.95 to 69.89). The negative predictive value was 100% (26/26) (86.77 to 100.00) and the positive predictive value was 28% (8/29) (12.37 to 47.24). CONCLUSION: Mucociliary transport is a non-invasive screening test that can be performed even in infants. The sensitivity of the test is high but its specificity is low. A normal test result excludes PCD.

Adolescent↗
PubMed2004

Genotype/phenotype correlation of the G85E mutation in a large cohort of cystic fibrosis patients.

In this European study, the phenotype in 68 patients, homozygous or compound heterozygous for the G85E mutation, was investigated. Each index case was compared with two cystic fibrosis (CF) patients from the same clinic, matched for age and sex: one with pancreatic sufficiency (PS) and one with pancreatic insufficiency (PI). When comparing 31 G85E/F508del and F508del/F508del patients, there were no differences in median age at diagnosis, mean sweat chloride value, most recent weight for height, most recent forced expiratory volume in one second % predicted, prevalence of chronic Pseudomonas aeruginosa colonisation and typical CF complications. However, PI was less frequent in the G85E/F508del group. Comparison of 55 G85E patients (with second mutation known and not classified as mild) with PS controls (n=44) showed that the G85E patients had a significantly higher sweat chloride, more often failure to thrive at diagnosis, higher prevalence of PI, worse current weight for height, higher prevalence of chronic P. aeruginosa colonisation and liver cirrhosis. Pulse-chase experiments revealed that G85E cystic fibrosis transmembrane conductance regulator failed to mature on a M470 as well as on a V470 background. Therefore, G85E is a class II mutation. Although there is variability in its clinical presentation, G85E mutation results in a severe phenotype.

Adolescent↗
PubMed2004

Epidemiology of Burkholderia cepacia complex colonisation in cystic fibrosis patients.

In Belgian cystic fibrosis (CF) clinics, sputum samples are evaluated on selective MAST medium routinely every 3 months. In this study, in 1993 and 1999, isolates were further examined by recA restriction fragment length polymorphism analysis and pulsed-field gel electrophoresis of genomic DNA restricted with SpeI. In 1993, 12 patients were colonised with Burkholderia cepacia complex (Bcc): B. cenocepacia (n=6), B. multivorans (n=3), B. stabilis (n=3). Four patients were colonised with the same B. cenocepacia strain; two with the same B. stabilis strain. After 5 yrs, three B. cenocepacia- and one B. multivorans-colonised patients had died. In 1999, Bcc was isolated in 12 patients: B. multivorans (n=9), B. stabilis (n=1) and B. cenocepacia (n=2). Three patients were colonised by the same B. multivorans strain. Compared to matched controls, the 5 yr outcome was poor; four B. cepacia patients died and none of the control patients died. Lung-function evolution was poor. In conclusion, the rate of colonisation in Belgian cystic fibrosis patients is stable and low. Burkholderia cenocepacia was most prevalent in 1993; Burkholderia multivorans in 1999. The cross-infection rate is low. Three patients had transient colonisation. The impact of Burkholderia cepacia complex on morbidity in the Belgian cystic fibrosis population is high and not limited to Burkholderia cenocepacia.

Adolescent↗
PubMed2002

Pediatric emergencies: thoracic emergencies.

Emergencies always require rapid diagnosis and an urgent or semi-urgent medical, interventional, or surgical action. In most cases radiology plays an essential role in making an accurate diagnosis. Reviewing the causes of acute respiratory pathology in the different pediatric age groups, we thought it would be interesting to divide the pathologies into two main parts: one part concerning pathologies involving the air flow and the other part concerning pathology affecting the pulmonary parenchyma. We acknowledge, however, that both conditions can occur concomitantly. The esophagus is another anatomic structure in the thorax that can be responsible for acute pathology in children. Acute pathology predominantly involving the air flow can be intrinsic and/or extrinsic, affecting the upper airways, trachea, main and segmental bronchi, and the small airways. Acute lung pathology can be congenital, infectious, or less frequently, tumoral or traumatic in children. Pleural pathology and cardiogenic emergencies are discussed also. Acute esophageal pathology is discussed briefly.

Child↗
PubMed2002

Variability of fecal pancreatic elastase measurements in cystic fibrosis patients.

BACKGROUND: the fecal pancreatic elastase-1 (EL-1) test is a new non-invasive test for pancreatic function. The aim of the study was to evaluate the intra-patient variability of the fecal EL-1 test in a cystic fibrosis (CF) population. METHODS: 26 CF patients were recruited. Mean patient (S.D.) age was 13.7 years (5.39). Nineteen patients had classical pancreatic insufficiency (PI) based on a clinical syndrome of malabsorption plus steatorrhea on a 72 h fecal fat balance. They were all treated with enzyme supplements. Four patients had classical pancreatic sufficiency (PS): no symptoms of malabsorption, no steatorrhea on a 72 h fecal fat balance, no enzyme treatment. Two patients had symptoms suggestive of PI but had a normal 72 h fecal fat balance: (doubtful pancreatic status (PD)). The CF patients were asked to collect stool samples on 7 consecutive days. EL-1 content in the samples was measured in duplicate. A cut-off of 200 microgEL-1/g stool was used for diagnosing PI. RESULTS: mean intra-assay variability was 4.06%. All PI patients had EL-1 levels below detection limit. For the PS group maximal intra-patient variability was 35%, one stool sample EL-1 level was below the 200-microg cut-off. In the PD group the maximal intra-patient variability was 37% and EL-1 levels were inconclusive for the diagnosis of PI in both patients. CONCLUSIONS: the EL-1 test can be used for diagnosing severe PI in CF patients with overt clinical symptoms of malabsorption. However, in CF patients where the clinical picture is less clear the EL-1 test may be inconclusive due to significant intra-patient variability.

Adolescent↗
PubMed2002

Evaluation of dietary fiber intake in Belgian children with cystic fibrosis: is there a link with gastrointestinal complaints?

BACKGROUND: Pancreatic enzyme replacement is the cornerstone of treating pancreatic insufficiency in patients with cystic fibrosis. Additionally, a high-calorie/high-fat diet is required to compensate for the increased energy requirement and the incomplete fat digestion. Even with adequate enzyme treatment, gastrointestinal problems, varying from simple constipation to inspissated stools, and distal intestinal obstruction syndrome (DIOS) may occur. Apart from residual fat malabsorption, a low fiber intake is suspected to be an underlying factor in gastrointestinal complaints. METHODS: We evaluated fiber intake in 40 patients with cystic fibrosis based on the dietary history method. Patients were classified according to gastrointestinal problems: group 1, no gastrointestinal complaints; group 2, nonspecific and mild gastrointestinal complaints; and group 3, documented DIOS. RESULTS: Overall fiber intake was adequate when compared with current recommendations. We could not show a relation between fiber intake and gastrointestinal complaints or DIOS. On the contrary, in patients with DIOS, fiber intake was higher, possibly as a therapeutic response to their gastrointestinal complaints. CONCLUSION: Overall fiber intake is adequate in our cystic fibrosis population. We could show no relation between low fiber intake and gastrointestinal problems in our patients with cystic fibrosis.

Adolescent↗
PubMed2001

Systemic cidofovir in papillomatosis.

An 8-year-old patient with severe recurrent respiratory papillomatosis and pulmonary spread was treated by systemic administration of cidofovir in association with laser treatment for tracheal lesions. Complete disappearance of the lesions in the pharynx and larynx and a significant yet incomplete regression in the bronchi and lung parenchyma were observed without deleterious side effects. This is the first case report of systemic use of cidofovir to treat recurrent respiratory papillomatosis.

Antiviral Agents↗
PubMed2001

Pulmonary sequestration: a comparison between pediatric and adult patients.

OBJECTIVE: Modern large single institutional reports on pulmonary sequestration (PS) are extremely rare. We were interested in comparing patients with PS referred by our pediatric versus adult pulmonologists. METHODS: Hospital notes of all patients operated on between 1978 and 1997 for a congenital broncho-pulmonary malformation were reviewed. In 28 patients, the parenchymal lesion was vascularized by a systemic artery and was separated from the bronchial tree, thus matching the strict definition of PS. Patient characteristics and outcome were analyzed comparing the pediatric group (< or =16 years: n=13; mean age, 3+/-5 years) versus the adult group (>16 years: n=15; mean age, 33+/-13 years). RESULTS: No significant differences between both groups were observed in sex, side, type of sequestration, pulmonary venous drainage, associated anomalies, hospital and late outcome, and patient's overall score. Patients (n=21) with the intralobar type of sequestration presented significantly more often with an infection when compared with patients (n=7) with the extralobar type (91 versus 14%; P=0.0033). When compared with the pediatric group, patients in the adult group had significantly more respiratory infections (87 versus 38%; P=0.016), and also required a lobectomy more often (67 versus 31%; P=0.056). CONCLUSIONS: The extralobar type of sequestration often remains asymptomatic, and is usually an incidental finding during infancy. The intralobar type mostly presents with recurrent infections in adulthood resulting in more lobectomies. We believe these findings support our current policy to remove any pulmonary malformation whenever diagnosed in order to: (1), prevent infection and other potentially serious late complications which may compromise the surgical outcome; and (2), enhance the chance of a parenchymal-sparing resection.

Adolescent↗
PubMed2001

Evaluation of impulse oscillation system: comparison with forced oscillation technique and body plethysmography.

The impulse oscillation system (IOS) has been developed recently to measure respiratory system resistance (Rrs) and reactance (Xrs) at different frequencies up to > or = 25 Hz. IOS has, however, not been validated against established techniques. This study compared IOS with the classical pseudorandom noise forced oscillation technique (FOT) and body plethysmographic airway resistance (Raw) in 49 subjects with a variety of lung disorders and a wide range of Raw (0.10-1.28 kPa x L(-1) x s). Rrs,IOS was slightly greater than Rrs,FOT, especially at lower frequencies, with a mean +/- SD difference at 5-6 Hz of 0.14 +/- 0.09 kPa x L(-1) x s. Comparisons with the wave-tube technique applied on two analogues indicated an overestimation by IOS. Xrs,IOS and Xrs,FOT were very similar, with a slightly higher resonant frequency with IOS than with FOT (mean difference +/- SD 1.35 +/- 3.40 Hz). Raw was only moderately correlated with Rrn,FOT and Rrs-IOS; although the mean differences were small (0.04 +/- 0.14 kPa x L(-1)s for Rrs6,FOT and -0.10 +/- 0.14 kPa x L(-1) x s for Rrs5,IOS), IOS and FOT markedly underestimated high resistance values. In conclusion, the impulse oscillation system yields respiratory system resistance and reactance values similar, but not identical to those provided by the forced oscillation technique.

Adolescent↗
PubMed2001

Bilateral cataract and high myopia in a child with trichothiodystrophy: a case report.

Trichothiodystrophy refers to a group of autosomal recessive disorders that have in common brittle sulphur-deficient hair (7). The abnormalities are usually obvious at birth and the clinical expression is variable. Ocular abnormalities are common with bilateral cataract being the most frequent one. We report on a four year old boy with trichothiodystrophy (complementation group TTD-A) who presented to us with strabismus, high myopia and bilateral cataract.

Abnormalities, Multiple↗
PubMed2000

Sputum induction in young cystic fibrosis patients.

A culture from the lower airway secretions is the optimal sample to guide antibiotic therapy in cystic fibrosis (CF) lung disease. The authors therefore examined whether sputum induction is an efficient, safe and acceptable procedure in CF children without spontaneous expectorations. Nineteen patients were studied. Their mean age (range) was 8.6 yrs (4.3-15.2 yrs). Their mean forced expiratory volume in one second (FEV1) was 88% predicted (46-122%). NaCl solutions from 0.9-6% were inhaled, after baseline lung function tests before and after salbutamol. All patients did produce secretions. Alveolar macrophages were present in 16/19 induced samples. The procedure induced minor but significant bronchoconstriction: the mean change (range) in postsalbutamol FEV1 (% pred) was -7 (-24-16). Percutaneous oxygen saturation remained above 90% in all children. The test had to be discontinued in one child because of cough and wheeze. Acceptability of the procedure evaluated using a visual analogue scale from -7-7 showed a mean value (range) at the final concentration of -1.23 (-6.16-5.88). It is concluded that sputum induction is possible, safe and acceptable in cystic fibrosis children who do not expectorate spontaneously.

Adolescent↗