Amir Szeinberg - Academia.edu (original) (raw)

Papers by Amir Szeinberg

Research paper thumbnail of Serum lipase levels pre and post Landh meal: Evaluation of exocrine pancreatic status in cystic fibrosis

International Journal of Clinical & Laboratory Research, 1998

Determination of pancreatic function is essential in cystic fibrosis. The most-reliable method is... more Determination of pancreatic function is essential in cystic fibrosis. The most-reliable method is by measuring pancreatic enzymes in the duodenum following intravenous or oral stimulation. However, this is invasive, time consuming, and expensive. Indirect tests are non-invasive but tack accuracy. This study examines a simple test which combines pancreatic stimulation by Lundh meal and sequential serum lipase measurements. The test was performed on three groups: group A, 36 cystic fibrosis patients carrying two mutations associated with severe disease and pancreatic insufficiency (AF508, W1282X, G542X, N1303K, $549R); group B, 8 compound heterozygote cystic fibrosis patients carrying one mutation causing mild disease with pancreatic sufficiency (3849 + 10 kb C ~ T); group C, 17 healthy individuals. Basal lipase levels were 2-16.5, 16.4-73, and 8.5-27.8 U/1 in groups A, B, and C, respectively, with some overlapping between groups. There were three patterns of lipase activity (1) consistently low levels (group A) suggested a severely affected insufficient pancreas; (2) normal basal levels followed by a linear rise peaking 30 rain after the meal (found in 16 of 17 healthy individuals and 3 patients of group B) reflecting an unaffected sufficient pancreas; (3) elevated lipase levels not influenced by the meal (5 patients of group B). This reflects an ongoing destructive process in the pancreas which will eventually result in conversion from pancreatic sufficiency to pancreatic insufficiency. Hence serum lipase activity prior to and 30 min after Lundh meal

Research paper thumbnail of Lundh meal: a single non-invasive challenge test for evaluation of exocrine and endocrine pancreatic function in cystic fibrosis patients

International Journal of Clinical & Laboratory Research, 1999

Research paper thumbnail of Child abuse, osteogenesis imperfecta and the grey zone between them

Journal of medicine, 1993

We report a child who was thought to suffer a non-accidental injury. The parents were unable to c... more We report a child who was thought to suffer a non-accidental injury. The parents were unable to convince the child abuse team of their innocence. The eruption of lucent teeth established the diagnosis of osteogenesis imperfecta type IVB.

Research paper thumbnail of The critical first six months in cystic fibrosis: A syndrome of severe bronchiolitis

Pediatric Pulmonology, 1997

The syndrome of infantile bronchiolitis in cystic fibrosis (CF) carries a high mortality. Fifteen... more The syndrome of infantile bronchiolitis in cystic fibrosis (CF) carries a high mortality. Fifteen cases of CF encountered over the past 19 years with severe bronchiolitis with onset during the first 6 months of life are described. Treatment included steroids in high doses. All patients recovered. Further progress resembled the usual natural course of CF and showed no evidence of persisting lung damage. The mechanism of this syndrome is not clear and is probably dependent on many factors involved in early lung disease in CF. The frequency of severe bronchiolitis in cystic fibrosis may not be high, but it continues to be seen in clinical practice today.

Research paper thumbnail of Ruptured interventricular septum after blunt chest trauma: Ultrasonographic diagnosis

Pediatric Cardiology, 1995

A 6-year-old child was found under a heavy bookcase that compressed her chest. On admission to th... more A 6-year-old child was found under a heavy bookcase that compressed her chest. On admission to the emergency room she was found to be dyspneic with a systolic murmur and complete atrioventricular (A-V) block. Her condition deteriorated rapidly, leading to cardiogenic shock and loss of consciousness. Echocardiographic Doppler evaluation demonstrated a large ventricular septal defect and tricuspid insufficiency. A pericardial patch was put over the tear in the septum, and torn chordae tendinae were reimplanted to the papillary muscles. A pacemaker was inserted. Her situation improved, but on the third day cardiogenic shock and right ventricular dysfunction ensued and the patient expired. A review of the previous 13 cases from the pediatric literature is presented.

Research paper thumbnail of Congenital bilateral absence of vas deferens in the absence of cystic fibrosis

Research paper thumbnail of Nephrotic syndrome and fibrillary glomerulonephritis

Journal of Internal Medicine, 1997

A 28-year-old female with cystic fibrosis presented with nephrotic syndrome and progressive renal... more A 28-year-old female with cystic fibrosis presented with nephrotic syndrome and progressive renal failure. In addition, she complained of blurred vision and there was a purpuric skin eruption localized to her legs. A renal biopsy revealed fibrillary glomerulonephritis. Skin biopsy demonstrated swelling of capillary endothelium, thickening of arteriolar walls and deposition of IgA, C3 and fibrinogen by immunofluorescence. Opthalmoscopy and fluorescein angiography disclosed cotton wool spots with intraretinal haemorrhages and ischaemia of the macula. Albumin infusions resulted in worsening of eye symptoms and signs. The presence of these three clinicopathologic entities in a patient with CF may indicate the possibility of systemic involvement related to continued exposure to chronic bacterial lower lung infection.

Research paper thumbnail of Similar levels of mRNA from the W1282X and the delta F508 cystic fibrosis alleles, in nasal epithelial cells

Journal of Clinical Investigation, 1994

The effect of nonsense mutations on mRNA levels is variable. The levels of some mRNAs are not aff... more The effect of nonsense mutations on mRNA levels is variable. The levels of some mRNAs are not affected and truncated proteins are produced, while the levels of others are severely decreased and null phenotypes are observed. The effect on mRNA levels is important for the understanding of phenotype-genotype association. Cystic fibrosis (CF) is a lethal autosomal recessive disease with variable clinical presentation. Recently, two CF patients with mild pulmonary disease carrying nonsense mutations (R553X, W1316X) were found to have severe deficiency of mRNA. In the Jewish Ashkenazi CF patient population, 60% of the chromosomes carry a nonsense mutation, W1282X. Patients homozygous for this mutation have severe disease presentation with variable pulmonary disease. The presence of CF transcripts in a group of patients homozygous and heterozygous for this mutation was studied by reverse transcriptase PCR of various regions of the gene. Subsequent hybridization to specific CF PCR probes and densitometry analysis indicated that the CF mRNA levels in patients homozygous for the W1282X mutation are not significantly decreased by the mutation. mRNA levels were compared for patients heterozygous for the W1282X mutation. The relative levels of mRNA with the W1282X, and the AF508 or the normal alleles, were similar in each patient. These results indicate that the severe clinical phenotype of patients carrying the W1282X mutation is not due to a severe deficiency of mRNA. In addition, the severity, progression, and variability of the pulmonary disease are affected by other, as yet unknown factors.

Research paper thumbnail of The relation between age and time to maximal bronchoconstriction following exercise in children

Respiratory Medicine, 2009

Background: The exercise challenge test (ECT) is a common tool for assessment of asthma in childr... more Background: The exercise challenge test (ECT) is a common tool for assessment of asthma in children. Many studies suggest that the ''time to maximal bronchoconstriction'' (Nadir-t) after exercise challenge in asthmatic children may be age-dependent, although this has never been systematically studied. Such findings may influence epidemiological surveys where the schedule of post-exercise measurements is trimmed. This study systematically assesses the relation between age and time to maximal bronchoconstriction post-ECT. Methods: Data were collected retrospectively from 131 subjects (87 male; 3e18 years) who were referred for ECT. The routine ECT was performed according to ATS recommendation of a 6-min run. Spirometry was measured at 1, 3, 5, 10, 15, and 20 min post-exercise. The post-exercise nadir of FEV 1 (%baseline) (FEV 1-nadir) and the time to maximal fall in Nadir-t (minutes) were sought and values were related to age. Results: Baseline FEV 1 values (mean AE SD) were 90.5 AE 13.8% predicted. FEV 1-nadir was À23.6 AE 11.7% from baseline values. The Nadir-t was reached at 5.1 AE 2.6 min (range 2e12 min). A positive correlation between children's age and Nadir-t was observed (r 2 Z 0.542; SD of residuals Z 1.79; p < 0.001), regardless of FEV 1-nadir, whether the cutoff of point was À10% or À15% of baseline FEV 1. Children <10 years of age showed Nadir-t at 3.4 AE 1.7 min post-exercise and older children at 6.6 AE 2.5 min post-exercise (p < 0.0001). Conclusion: Our results indicate that the time to maximal bronchoconstriction is agedependent in children and adolescents, and imply that the schedule of post-exercise FEV 1 measurements should be cautiously trimmed.

Research paper thumbnail of Exercise Challenge Test in 3- to 6-Year-Old Asthmatic Children

Chest, 2007

The exercise challenge test (ECT) is a common tool to assess exercise-induced asthma (EIA) in sch... more The exercise challenge test (ECT) is a common tool to assess exercise-induced asthma (EIA) in school-aged children. EIA has not been explored in the early childhood setting. Objective: To assess the existence of EIA in children in this age group. Measurements and main results: A 6-min, controlled, free-run test was performed in 55 children (age range, 3 to 6 years old) who were classified into the following groups: 30 children in whom asthma had been previously diagnosed (group A); and 25 children with prolonged coughing (group B). Spirometry measurements were obtained before the run, and at 1, 2, 3, 5, 10, and 20 min after the run. A positive finding of EIA was defined as a 13% decrease from baseline FEV 1 or baseline forced expiratory volume in the first 0.5 s (FEV 0.5). The actual duration of each run was age-related (mean [؎ SD] duration, 4.8 ؎ 0.8 min). The nadir in indexes occurred after a mean time of 2.98 ؎ 1.31 min. A positive EIA finding determined by FEV 1 was present in 15 children, and by FEV 0.5 in 34 children. Twenty-six children were from group A, but only 8 children were from group B. Wheezing and/or prolonged expiration were associated with a positive test result in 31 of 34 children. Coughing was frequent in children with both negative and positive ECT findings. Conclusion: The present study documents for the first time the presence of EIA in response to a free-run test in early childhood. Our findings suggest that a free-run test for the presence of EIA is suitable, but that the running duration is limited by age. The duration of airflow limitation after exercise is significantly earlier and shorter in young children with asthma compared with older children. FEV 0.5 is a better index than the traditional FEV 1 for describing positive ECT results in young children. The association of wheezing and/or prolonged expiration may help in defining EIA in early childhood in the absence of a spirometer.

Research paper thumbnail of Effects of a movement and swimming program on vital capacity and water orientation skills of children with cerebral palsy

Developmental Medicine & Child Neurology, 2008

Wcng TR. Levison H. (1969) Standards of pulmonary function in Whitley JD. Schwnc LL. (1987) Compa... more Wcng TR. Levison H. (1969) Standards of pulmonary function in Whitley JD. Schwnc LL. (1987) Comparison o f heart rate children. American Rei?iew of Respiratory Disease 91: 879-94. responses: water walking versus treadmill wallung. Physical 't7ierapy67: 1501-3. Movement and Swimming Program in CP lksbuyabu Hutzleretal.

Research paper thumbnail of A. AugartenG. ParetI. AvneriH. AkonsM. AviramL. BenturH. BlauO. EfratiA. Szeinberg A. BarakE. KeremJ. Yahav Systemic inflammatory mediators and cystic fibrosis genotype

Research paper thumbnail of CAN RESPIRATORY MUSCLE STRENGTH AND VITAL CAPACITYSERVE AS INDICES FOR THE DEVELOPMENT OF HYPERCAPNEIC RESPIRATORY FAILURE IN DOUCHENNE'S MUSCULAR DYSTROPHY?

Research paper thumbnail of Pentamidine-induced torsades de pointes

The Pediatric infectious disease journal, 1993

Research paper thumbnail of Heliox in respiratory failure secondary to bronchiolitis: A new therapy

Pediatric Pulmonology, 1996

Research paper thumbnail of Spiral CT and 3D Image Reconstruction of Vascular Rings and Associated Tracheobronchial Anomalies

Journal of Computer Assisted Tomography, 1995

Spiral CT (SCT) angiography and three-dimensional (3D) reconstruction methods represent noninvasi... more Spiral CT (SCT) angiography and three-dimensional (3D) reconstruction methods represent noninvasive tools in diagnosis of vascular rings and associated tracheobronchial anomalies in the pediatric age group. Three patients suspected on clinical and conventional radiological grounds of having vascular and tracheobronchial anomalies were examined using SCT. Three-dimensional images were reconstructed using a surface rendering technique. In one case the diagnosis of complete double aortic arch was confirmed by angiography. In the other two patients the SCT and 3D reconstruction established the diagnosis of pulmonary sling and right aortic arch associated with left aberrant subclavian artery and angiography could be avoided. Spiral CT and color-coded 3D reconstruction represent important additional tools and perhaps alternatives to angiography or other noninvasive techniques used in evaluation of vascular anomalies of the thoracic aorta and pulmonary arteries in infants and children.

Research paper thumbnail of Hospital Versus Home Treatment For Acute Infectious Respiratory Exacerbations In Cystic Fibrosis

A53. CYSTIC FIBROSIS: CLINICAL PEDIATRIC STUDIES, 2010

Research paper thumbnail of The relation between age and time to maximal bronchoconstriction following exercise in children

Respiratory Medicine, 2009

Background: The exercise challenge test (ECT) is a common tool for assessment of asthma in childr... more Background: The exercise challenge test (ECT) is a common tool for assessment of asthma in children. Many studies suggest that the ''time to maximal bronchoconstriction'' (Nadir-t) after exercise challenge in asthmatic children may be age-dependent, although this has never been systematically studied. Such findings may influence epidemiological surveys where the schedule of post-exercise measurements is trimmed. This study systematically assesses the relation between age and time to maximal bronchoconstriction post-ECT. Methods: Data were collected retrospectively from 131 subjects (87 male; 3e18 years) who were referred for ECT. The routine ECT was performed according to ATS recommendation of a 6-min run. Spirometry was measured at 1, 3, 5, 10, 15, and 20 min post-exercise. The post-exercise nadir of FEV 1 (%baseline) (FEV 1 -nadir) and the time to maximal fall in Nadir-t (minutes) were sought and values were related to age. Results: Baseline FEV 1 values (mean AE SD) were 90.5 AE 13.8% predicted. FEV 1 -nadir was À23.6 AE 11.7% from baseline values. The Nadir-t was reached at 5.1 AE 2.6 min (range 2e12 min). A positive correlation between children's age and Nadir-t was observed (r 2 Z 0.542; SD of residuals Z 1.79; p < 0.001), regardless of FEV 1 -nadir, whether the cutoff of point was À10% or À15% of baseline FEV 1 .C h i l d r e n<10 years of age showed Nadir-t at 3.4 AE 1.7 min post-exercise and older children at 6.6 AE 2.5 min post-exercise (p < 0.0001). Conclusion: Our results indicate that the time to maximal bronchoconstriction is agedependent in children and adolescents, and imply that the schedule of post-exercise FEV 1 measurements should be cautiously trimmed. ª

Research paper thumbnail of Prediction of mortality and timing of referral for lung transplantation in cystic fibrosis patients

Pediatric Transplantation, 2001

Lung transplantation (Tx) is an optional treatment for cystic fibrosis (CF) patients with end-sta... more Lung transplantation (Tx) is an optional treatment for cystic fibrosis (CF) patients with end-stage lung disease. The decision to place a patient on the Tx waiting list is frequently complex, difficult, and controversial. This study evaluated the current criteria for lung.Tx and assessed additional parameters that may identify CF patients at high risk of death. Data were extracted from the medical records of 392 CF patients. Forty of these.patients had a forced expiratory volume in 1 s (FEV 1 ) less than 30% predicted, and nine of these 40 patients were transplanted. A comparison was performed between the survival of those transplanted (n59) and those not transplanted (n531), by means of Kaplan-Meier survival curves. The influence on survival of age, gender, nutritional status, sputum aspergillus, diabetes mellitus, recurrent hemoptysis, oxygen use, and the decline rate of FEV 1 , were investigated by means of univariate and multivariate analyses. The rate of decline of FEV 1 was evaluated employing the linear regression model. CF patients with a FEV 1 ,30% and who did not receive a lung transplant had survived longer than CF patients who did receive a lung transplant. (median survival 7.33 vs. 3.49 yr, 5-yr survival 73% vs. 29%). Two factors -rate of decline in FEV 1 values and age ,15 yr -were found to influence the mortality rate, while the other parameters examined did not. Our results indicate that the current criterion of FEV 1 ,30% predicted, alone is not sufficiently sensitive to predict the mortality rate in CF patients and time of referral for Tx, as many of these patients survive for long periods of time. Additional criteria to FEV 1 ,30%, should include rapidly declining FEV 1 values and age ,15 yr..

Research paper thumbnail of The significance of sweat Cl/Na ratio in patients with borderline sweat test

Pediatric Pulmonology, 1995

Recently a few cystic fibrosis (CF) patients with borderline or normal sweat tests have been repo... more Recently a few cystic fibrosis (CF) patients with borderline or normal sweat tests have been reported. These patients present a diagnostic challenge. We aimed to study the sweat Cl/Na ratio in cystic fibrosis patients and to assess whether this ratio could be used as a diagnostic criteria. The mean sweat Cl/Na ratio of 3 groups was compared: Group A: 71 CF patients carrying 2 mutations known to be associated with severe disease presentation (delta F508, W1282X, G542X, N1303K, 1717-1G --&amp;amp;amp;amp;gt; A). Group B: 10 compound heterozygous patients who carry one mutation associated with mild clinical disease (3849 + 10 kb --&amp;amp;amp;amp;gt; T). Group C: 142 normal subjects. Sweat chloride levels higher than those of sodium were found in 96% of patients in Group A as compared to 3% of patients in Group C. In Group B 40% of the patients had sweat chloride levels higher than or equal to sodium levels. The mean Cl/Na ratio of Group A (1.2 +/- 0.1) differed significantly from that of Group B (0.94 +/- 0.1) and both groups had significant higher mean Cl/Na ratio compared to Group C (0.7 +/- 0.4) (P &amp;amp;amp;amp;lt; 0.001). Thus in individuals with a borderline sweat test and a Cl/Na ratio &amp;amp;amp;amp;gt; or = 1 the diagnosis of CF should be considered. However, a Cl/Na ratio &amp;amp;amp;amp;lt; 1 does not exclude CF, since patients carrying mild mutations may have sweat sodium levels higher than those of chloride. Our findings suggest that the sweat Cl/Na ratio in CF is genetically determined and it may be of help in establishing the diagnosis of CF in patients with a borderline sweat test.

Research paper thumbnail of Serum lipase levels pre and post Landh meal: Evaluation of exocrine pancreatic status in cystic fibrosis

International Journal of Clinical & Laboratory Research, 1998

Determination of pancreatic function is essential in cystic fibrosis. The most-reliable method is... more Determination of pancreatic function is essential in cystic fibrosis. The most-reliable method is by measuring pancreatic enzymes in the duodenum following intravenous or oral stimulation. However, this is invasive, time consuming, and expensive. Indirect tests are non-invasive but tack accuracy. This study examines a simple test which combines pancreatic stimulation by Lundh meal and sequential serum lipase measurements. The test was performed on three groups: group A, 36 cystic fibrosis patients carrying two mutations associated with severe disease and pancreatic insufficiency (AF508, W1282X, G542X, N1303K, $549R); group B, 8 compound heterozygote cystic fibrosis patients carrying one mutation causing mild disease with pancreatic sufficiency (3849 + 10 kb C ~ T); group C, 17 healthy individuals. Basal lipase levels were 2-16.5, 16.4-73, and 8.5-27.8 U/1 in groups A, B, and C, respectively, with some overlapping between groups. There were three patterns of lipase activity (1) consistently low levels (group A) suggested a severely affected insufficient pancreas; (2) normal basal levels followed by a linear rise peaking 30 rain after the meal (found in 16 of 17 healthy individuals and 3 patients of group B) reflecting an unaffected sufficient pancreas; (3) elevated lipase levels not influenced by the meal (5 patients of group B). This reflects an ongoing destructive process in the pancreas which will eventually result in conversion from pancreatic sufficiency to pancreatic insufficiency. Hence serum lipase activity prior to and 30 min after Lundh meal

Research paper thumbnail of Lundh meal: a single non-invasive challenge test for evaluation of exocrine and endocrine pancreatic function in cystic fibrosis patients

International Journal of Clinical & Laboratory Research, 1999

Research paper thumbnail of Child abuse, osteogenesis imperfecta and the grey zone between them

Journal of medicine, 1993

We report a child who was thought to suffer a non-accidental injury. The parents were unable to c... more We report a child who was thought to suffer a non-accidental injury. The parents were unable to convince the child abuse team of their innocence. The eruption of lucent teeth established the diagnosis of osteogenesis imperfecta type IVB.

Research paper thumbnail of The critical first six months in cystic fibrosis: A syndrome of severe bronchiolitis

Pediatric Pulmonology, 1997

The syndrome of infantile bronchiolitis in cystic fibrosis (CF) carries a high mortality. Fifteen... more The syndrome of infantile bronchiolitis in cystic fibrosis (CF) carries a high mortality. Fifteen cases of CF encountered over the past 19 years with severe bronchiolitis with onset during the first 6 months of life are described. Treatment included steroids in high doses. All patients recovered. Further progress resembled the usual natural course of CF and showed no evidence of persisting lung damage. The mechanism of this syndrome is not clear and is probably dependent on many factors involved in early lung disease in CF. The frequency of severe bronchiolitis in cystic fibrosis may not be high, but it continues to be seen in clinical practice today.

Research paper thumbnail of Ruptured interventricular septum after blunt chest trauma: Ultrasonographic diagnosis

Pediatric Cardiology, 1995

A 6-year-old child was found under a heavy bookcase that compressed her chest. On admission to th... more A 6-year-old child was found under a heavy bookcase that compressed her chest. On admission to the emergency room she was found to be dyspneic with a systolic murmur and complete atrioventricular (A-V) block. Her condition deteriorated rapidly, leading to cardiogenic shock and loss of consciousness. Echocardiographic Doppler evaluation demonstrated a large ventricular septal defect and tricuspid insufficiency. A pericardial patch was put over the tear in the septum, and torn chordae tendinae were reimplanted to the papillary muscles. A pacemaker was inserted. Her situation improved, but on the third day cardiogenic shock and right ventricular dysfunction ensued and the patient expired. A review of the previous 13 cases from the pediatric literature is presented.

Research paper thumbnail of Congenital bilateral absence of vas deferens in the absence of cystic fibrosis

Research paper thumbnail of Nephrotic syndrome and fibrillary glomerulonephritis

Journal of Internal Medicine, 1997

A 28-year-old female with cystic fibrosis presented with nephrotic syndrome and progressive renal... more A 28-year-old female with cystic fibrosis presented with nephrotic syndrome and progressive renal failure. In addition, she complained of blurred vision and there was a purpuric skin eruption localized to her legs. A renal biopsy revealed fibrillary glomerulonephritis. Skin biopsy demonstrated swelling of capillary endothelium, thickening of arteriolar walls and deposition of IgA, C3 and fibrinogen by immunofluorescence. Opthalmoscopy and fluorescein angiography disclosed cotton wool spots with intraretinal haemorrhages and ischaemia of the macula. Albumin infusions resulted in worsening of eye symptoms and signs. The presence of these three clinicopathologic entities in a patient with CF may indicate the possibility of systemic involvement related to continued exposure to chronic bacterial lower lung infection.

Research paper thumbnail of Similar levels of mRNA from the W1282X and the delta F508 cystic fibrosis alleles, in nasal epithelial cells

Journal of Clinical Investigation, 1994

The effect of nonsense mutations on mRNA levels is variable. The levels of some mRNAs are not aff... more The effect of nonsense mutations on mRNA levels is variable. The levels of some mRNAs are not affected and truncated proteins are produced, while the levels of others are severely decreased and null phenotypes are observed. The effect on mRNA levels is important for the understanding of phenotype-genotype association. Cystic fibrosis (CF) is a lethal autosomal recessive disease with variable clinical presentation. Recently, two CF patients with mild pulmonary disease carrying nonsense mutations (R553X, W1316X) were found to have severe deficiency of mRNA. In the Jewish Ashkenazi CF patient population, 60% of the chromosomes carry a nonsense mutation, W1282X. Patients homozygous for this mutation have severe disease presentation with variable pulmonary disease. The presence of CF transcripts in a group of patients homozygous and heterozygous for this mutation was studied by reverse transcriptase PCR of various regions of the gene. Subsequent hybridization to specific CF PCR probes and densitometry analysis indicated that the CF mRNA levels in patients homozygous for the W1282X mutation are not significantly decreased by the mutation. mRNA levels were compared for patients heterozygous for the W1282X mutation. The relative levels of mRNA with the W1282X, and the AF508 or the normal alleles, were similar in each patient. These results indicate that the severe clinical phenotype of patients carrying the W1282X mutation is not due to a severe deficiency of mRNA. In addition, the severity, progression, and variability of the pulmonary disease are affected by other, as yet unknown factors.

Research paper thumbnail of The relation between age and time to maximal bronchoconstriction following exercise in children

Respiratory Medicine, 2009

Background: The exercise challenge test (ECT) is a common tool for assessment of asthma in childr... more Background: The exercise challenge test (ECT) is a common tool for assessment of asthma in children. Many studies suggest that the ''time to maximal bronchoconstriction'' (Nadir-t) after exercise challenge in asthmatic children may be age-dependent, although this has never been systematically studied. Such findings may influence epidemiological surveys where the schedule of post-exercise measurements is trimmed. This study systematically assesses the relation between age and time to maximal bronchoconstriction post-ECT. Methods: Data were collected retrospectively from 131 subjects (87 male; 3e18 years) who were referred for ECT. The routine ECT was performed according to ATS recommendation of a 6-min run. Spirometry was measured at 1, 3, 5, 10, 15, and 20 min post-exercise. The post-exercise nadir of FEV 1 (%baseline) (FEV 1-nadir) and the time to maximal fall in Nadir-t (minutes) were sought and values were related to age. Results: Baseline FEV 1 values (mean AE SD) were 90.5 AE 13.8% predicted. FEV 1-nadir was À23.6 AE 11.7% from baseline values. The Nadir-t was reached at 5.1 AE 2.6 min (range 2e12 min). A positive correlation between children's age and Nadir-t was observed (r 2 Z 0.542; SD of residuals Z 1.79; p < 0.001), regardless of FEV 1-nadir, whether the cutoff of point was À10% or À15% of baseline FEV 1. Children <10 years of age showed Nadir-t at 3.4 AE 1.7 min post-exercise and older children at 6.6 AE 2.5 min post-exercise (p < 0.0001). Conclusion: Our results indicate that the time to maximal bronchoconstriction is agedependent in children and adolescents, and imply that the schedule of post-exercise FEV 1 measurements should be cautiously trimmed.

Research paper thumbnail of Exercise Challenge Test in 3- to 6-Year-Old Asthmatic Children

Chest, 2007

The exercise challenge test (ECT) is a common tool to assess exercise-induced asthma (EIA) in sch... more The exercise challenge test (ECT) is a common tool to assess exercise-induced asthma (EIA) in school-aged children. EIA has not been explored in the early childhood setting. Objective: To assess the existence of EIA in children in this age group. Measurements and main results: A 6-min, controlled, free-run test was performed in 55 children (age range, 3 to 6 years old) who were classified into the following groups: 30 children in whom asthma had been previously diagnosed (group A); and 25 children with prolonged coughing (group B). Spirometry measurements were obtained before the run, and at 1, 2, 3, 5, 10, and 20 min after the run. A positive finding of EIA was defined as a 13% decrease from baseline FEV 1 or baseline forced expiratory volume in the first 0.5 s (FEV 0.5). The actual duration of each run was age-related (mean [؎ SD] duration, 4.8 ؎ 0.8 min). The nadir in indexes occurred after a mean time of 2.98 ؎ 1.31 min. A positive EIA finding determined by FEV 1 was present in 15 children, and by FEV 0.5 in 34 children. Twenty-six children were from group A, but only 8 children were from group B. Wheezing and/or prolonged expiration were associated with a positive test result in 31 of 34 children. Coughing was frequent in children with both negative and positive ECT findings. Conclusion: The present study documents for the first time the presence of EIA in response to a free-run test in early childhood. Our findings suggest that a free-run test for the presence of EIA is suitable, but that the running duration is limited by age. The duration of airflow limitation after exercise is significantly earlier and shorter in young children with asthma compared with older children. FEV 0.5 is a better index than the traditional FEV 1 for describing positive ECT results in young children. The association of wheezing and/or prolonged expiration may help in defining EIA in early childhood in the absence of a spirometer.

Research paper thumbnail of Effects of a movement and swimming program on vital capacity and water orientation skills of children with cerebral palsy

Developmental Medicine & Child Neurology, 2008

Wcng TR. Levison H. (1969) Standards of pulmonary function in Whitley JD. Schwnc LL. (1987) Compa... more Wcng TR. Levison H. (1969) Standards of pulmonary function in Whitley JD. Schwnc LL. (1987) Comparison o f heart rate children. American Rei?iew of Respiratory Disease 91: 879-94. responses: water walking versus treadmill wallung. Physical 't7ierapy67: 1501-3. Movement and Swimming Program in CP lksbuyabu Hutzleretal.

Research paper thumbnail of A. AugartenG. ParetI. AvneriH. AkonsM. AviramL. BenturH. BlauO. EfratiA. Szeinberg A. BarakE. KeremJ. Yahav Systemic inflammatory mediators and cystic fibrosis genotype

Research paper thumbnail of CAN RESPIRATORY MUSCLE STRENGTH AND VITAL CAPACITYSERVE AS INDICES FOR THE DEVELOPMENT OF HYPERCAPNEIC RESPIRATORY FAILURE IN DOUCHENNE'S MUSCULAR DYSTROPHY?

Research paper thumbnail of Pentamidine-induced torsades de pointes

The Pediatric infectious disease journal, 1993

Research paper thumbnail of Heliox in respiratory failure secondary to bronchiolitis: A new therapy

Pediatric Pulmonology, 1996

Research paper thumbnail of Spiral CT and 3D Image Reconstruction of Vascular Rings and Associated Tracheobronchial Anomalies

Journal of Computer Assisted Tomography, 1995

Spiral CT (SCT) angiography and three-dimensional (3D) reconstruction methods represent noninvasi... more Spiral CT (SCT) angiography and three-dimensional (3D) reconstruction methods represent noninvasive tools in diagnosis of vascular rings and associated tracheobronchial anomalies in the pediatric age group. Three patients suspected on clinical and conventional radiological grounds of having vascular and tracheobronchial anomalies were examined using SCT. Three-dimensional images were reconstructed using a surface rendering technique. In one case the diagnosis of complete double aortic arch was confirmed by angiography. In the other two patients the SCT and 3D reconstruction established the diagnosis of pulmonary sling and right aortic arch associated with left aberrant subclavian artery and angiography could be avoided. Spiral CT and color-coded 3D reconstruction represent important additional tools and perhaps alternatives to angiography or other noninvasive techniques used in evaluation of vascular anomalies of the thoracic aorta and pulmonary arteries in infants and children.

Research paper thumbnail of Hospital Versus Home Treatment For Acute Infectious Respiratory Exacerbations In Cystic Fibrosis

A53. CYSTIC FIBROSIS: CLINICAL PEDIATRIC STUDIES, 2010

Research paper thumbnail of The relation between age and time to maximal bronchoconstriction following exercise in children

Respiratory Medicine, 2009

Background: The exercise challenge test (ECT) is a common tool for assessment of asthma in childr... more Background: The exercise challenge test (ECT) is a common tool for assessment of asthma in children. Many studies suggest that the ''time to maximal bronchoconstriction'' (Nadir-t) after exercise challenge in asthmatic children may be age-dependent, although this has never been systematically studied. Such findings may influence epidemiological surveys where the schedule of post-exercise measurements is trimmed. This study systematically assesses the relation between age and time to maximal bronchoconstriction post-ECT. Methods: Data were collected retrospectively from 131 subjects (87 male; 3e18 years) who were referred for ECT. The routine ECT was performed according to ATS recommendation of a 6-min run. Spirometry was measured at 1, 3, 5, 10, 15, and 20 min post-exercise. The post-exercise nadir of FEV 1 (%baseline) (FEV 1 -nadir) and the time to maximal fall in Nadir-t (minutes) were sought and values were related to age. Results: Baseline FEV 1 values (mean AE SD) were 90.5 AE 13.8% predicted. FEV 1 -nadir was À23.6 AE 11.7% from baseline values. The Nadir-t was reached at 5.1 AE 2.6 min (range 2e12 min). A positive correlation between children's age and Nadir-t was observed (r 2 Z 0.542; SD of residuals Z 1.79; p < 0.001), regardless of FEV 1 -nadir, whether the cutoff of point was À10% or À15% of baseline FEV 1 .C h i l d r e n<10 years of age showed Nadir-t at 3.4 AE 1.7 min post-exercise and older children at 6.6 AE 2.5 min post-exercise (p < 0.0001). Conclusion: Our results indicate that the time to maximal bronchoconstriction is agedependent in children and adolescents, and imply that the schedule of post-exercise FEV 1 measurements should be cautiously trimmed. ª

Research paper thumbnail of Prediction of mortality and timing of referral for lung transplantation in cystic fibrosis patients

Pediatric Transplantation, 2001

Lung transplantation (Tx) is an optional treatment for cystic fibrosis (CF) patients with end-sta... more Lung transplantation (Tx) is an optional treatment for cystic fibrosis (CF) patients with end-stage lung disease. The decision to place a patient on the Tx waiting list is frequently complex, difficult, and controversial. This study evaluated the current criteria for lung.Tx and assessed additional parameters that may identify CF patients at high risk of death. Data were extracted from the medical records of 392 CF patients. Forty of these.patients had a forced expiratory volume in 1 s (FEV 1 ) less than 30% predicted, and nine of these 40 patients were transplanted. A comparison was performed between the survival of those transplanted (n59) and those not transplanted (n531), by means of Kaplan-Meier survival curves. The influence on survival of age, gender, nutritional status, sputum aspergillus, diabetes mellitus, recurrent hemoptysis, oxygen use, and the decline rate of FEV 1 , were investigated by means of univariate and multivariate analyses. The rate of decline of FEV 1 was evaluated employing the linear regression model. CF patients with a FEV 1 ,30% and who did not receive a lung transplant had survived longer than CF patients who did receive a lung transplant. (median survival 7.33 vs. 3.49 yr, 5-yr survival 73% vs. 29%). Two factors -rate of decline in FEV 1 values and age ,15 yr -were found to influence the mortality rate, while the other parameters examined did not. Our results indicate that the current criterion of FEV 1 ,30% predicted, alone is not sufficiently sensitive to predict the mortality rate in CF patients and time of referral for Tx, as many of these patients survive for long periods of time. Additional criteria to FEV 1 ,30%, should include rapidly declining FEV 1 values and age ,15 yr..

Research paper thumbnail of The significance of sweat Cl/Na ratio in patients with borderline sweat test

Pediatric Pulmonology, 1995

Recently a few cystic fibrosis (CF) patients with borderline or normal sweat tests have been repo... more Recently a few cystic fibrosis (CF) patients with borderline or normal sweat tests have been reported. These patients present a diagnostic challenge. We aimed to study the sweat Cl/Na ratio in cystic fibrosis patients and to assess whether this ratio could be used as a diagnostic criteria. The mean sweat Cl/Na ratio of 3 groups was compared: Group A: 71 CF patients carrying 2 mutations known to be associated with severe disease presentation (delta F508, W1282X, G542X, N1303K, 1717-1G --&amp;amp;amp;amp;gt; A). Group B: 10 compound heterozygous patients who carry one mutation associated with mild clinical disease (3849 + 10 kb --&amp;amp;amp;amp;gt; T). Group C: 142 normal subjects. Sweat chloride levels higher than those of sodium were found in 96% of patients in Group A as compared to 3% of patients in Group C. In Group B 40% of the patients had sweat chloride levels higher than or equal to sodium levels. The mean Cl/Na ratio of Group A (1.2 +/- 0.1) differed significantly from that of Group B (0.94 +/- 0.1) and both groups had significant higher mean Cl/Na ratio compared to Group C (0.7 +/- 0.4) (P &amp;amp;amp;amp;lt; 0.001). Thus in individuals with a borderline sweat test and a Cl/Na ratio &amp;amp;amp;amp;gt; or = 1 the diagnosis of CF should be considered. However, a Cl/Na ratio &amp;amp;amp;amp;lt; 1 does not exclude CF, since patients carrying mild mutations may have sweat sodium levels higher than those of chloride. Our findings suggest that the sweat Cl/Na ratio in CF is genetically determined and it may be of help in establishing the diagnosis of CF in patients with a borderline sweat test.