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Quantum 1/f noise is the manifestation of the coherent and conventional quantum 1/f effects (Q1/fE). The conventional Q1/fE is a fundamental quantum fluctuation of physical cross sections σ and process rates Γ, caused by the bremsstrahlung (recoil) energy and momentum losses of charged particles, when they are scattered, or accelerated in any way. The closely related coherent Q1/fE is present in any current carried by many particles. It is caused by the energy spread characterizing any coherent state of the electromagnetic field oscillators. According to the Heisenberg's uncertainty principle, because an approximation of the phase or position variable is known, exact knowledge of the energy is precluded. This energy spread results in nonstationary energy values, or fluctuations in the energy of the oscillators. To find the spectral density of these inescapable basic fluctuations, which are known to characterize any quantum state, which is not an energy eigenstate, we use an elementary physical derivation based on Schrödinger's definition of coherent states, which can be supplemented by a rigorous derivation from a well-known quantum-electrodynamical branch-point propagator. The example of a simple harmonic oscillator is also useful for illustrating the uncertainty that arises due to Q 1/f Noise. Clearly illustrating the relation between the uncertainty principle and Q 1/f noise.

Progression of pulmonary sarcoidosis in children remains poorly documented. The aim of this work was to gather follow-up information on pulmonary outcomes in children with sarcoidosis and to obtain data of relevance to a discussion of the optimal length and regimen of glucocorticoid therapy.In the present study, the authors experience of pulmonary sarcoidosis in 21 children referred to the paediatric pulmonary department over a 10-yr period is reported with a documented follow-up of at least 4 yr. Evaluation of the disease during the follow-up included analysis of clinical manifestations, chest radiographs, pulmonary function tests with measurements of the vital capacity (VC), dynamic lung compliance (CL,dyn), lung transfer for CO (TL,CO), and arterial blood gases, as well as bronchoalveolar lavage (BAL) with determination of total and differential cell counts.After initial evaluation the decision was a careful observation of four children without therapy. Corticosteroid treatment was initiated in 17 children. Analysis of results indicated that after 6–12 months of treatment most clinical manifestations of the disease and chest radiograph abnormalities disappeared, and beneficial effects on VC andTL,COwere apparent. After 18 months of steroids no benefit on pulmonary function tests could be noticed, with mainly persistence of alterations ofCL,dyn. Results of BAL studies documented the presence of an alveolitis with increased lymphocyte populations throughout the follow-up. Relapses were observed in four children during tapering of prednisone; they were not reported after discontinuation of steroid therapy.Taken together data obtained in the presented population can lead to the following suggestions for the management of pulmonary sarcoidosis in children. BAL should be performed at the initial evaluation to document alveolitis; however, nothing seems to be gained from repeating this investigation during follow-up in the absence of specific reasons. Once the decision to initiate glucocorticoid therapy is made, 18 months may be a reasonable treatment duration. Discontinuation of therapy can be decided even if the pulmonary function tests remain abnormal, but the child should then be carefully monitored for a relapse.

The dominant role of inflammation in airways disease progression in cystic fibrosis (CF) is now well established and, based on recent findings, the possibility of an inappropriate inflammatory response in the lung of patients with CF has emerged. In order to characterize this response, the aim of the present work was to evaluate the levels of a number of pro- and anti-inflammatory cytokines in the sputum of CF children and to compare these levels to those observed in the sputum from non-CF children with diffuse bronchiectasis (DB). Three groups of patients were investigated: a group of 25 CF children (mean age: 12.2 yrs), a group of 10 non-CF children with DB (mean age 11.5 yrs), and a group of five healthy young adults (mean age 24 yrs). Elevated concentrations of pro-inflammatory cytokines, tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-8 were found in children with CF and in non-CF children with DB, with significantly higher concentrations of IL-1beta in CF children. Analysis of the natural anti-inflammatory cytokine IL-1 receptor antagonist (IL-1ra) and type II TNF soluble receptor (sTNFRII) concentrations showed distinct patterns, with elevated levels of both inhibitors in CF patients, whereas only sTNFRII was found to be increased in non-CF children with DB. IL-10 data indicated low concentrations in the CF group. In all CF children, the concentrations of IL-6 in the airways were extremely low, independent of the clinical, bacteriological or functional status. By contrast, significantly increased IL-6 levels were found in non-CF children with DB. These results document distinct cytokine profiles in cystic fibrosis patients and noncystic fibrosis patients. They also suggest that impairment of interleukin-6 expression may represent an important component of the excessive inflammatory response observed in cystic fibrosis.

The involvement of the insulin-like growth factor (IGF) system in lung growth and repair following injury is sustained by a number of studies. Based on this knowledge, the aim of the present work was to document the expression of the IGFs and their binding proteins by alveolar cells obtained by bronchoalveolar lavage (BAL). Two groups were investigated: a control group of five children and a group of 11 children referred to the department for exploration of interstitial lung disease (ILD). Components of the IGF system studied included IGF-I, IGF-II and IGF-binding proteins (IGFBP). Expression of these factors was analysed at the level of messenger ribonucleic acid (mRNA) (by semi-quantitative reverse transcription polymerase chain reaction techniques), and of protein for the IGFBPs. In addition, expression of two major cytokines associated with the inflammatory process, tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta), was also documented. In children without parenchymal disease, the growth factor expressed was IGF-I, in association with the presence of mRNA for IGFBP-2 in all cases. In children with ILD, expression of IGF-I was observed in nine patients and of IGF-II in three patients, and the presence of IGFBP-2 was found in all extracts analysed (mRNA and proteins). Evaluation of IGFBP-2 expression indicated an increase in the group of children with ILD. Interestingly, a significant association was observed between the increase in IGFBP-2 expression and TGF-beta expression. The present data emphasize the presence on insulin-like growth factor-binding protein-2 in the BAL of all patients, and suggest that this protein may be an important factor of the injury/repair processes during the progression of alveolar inflammation.

Resume L'atteinte tuberculeuse au cours de la mucoviscidose n'a, curieusement, ete rapportee que tres rarement. Observation. Une adolescente de 14 ans, atteinte d'une mucoviscidose evoluant sur le mode subaigu habituel et regulierement suivie, est prise en charge devant l'apparition de deux foyers au niveau du poumon gauche, resistant au traitement habituel de la mucoviscidose. La decouverte de bacilles tuberculeux par culture sur milieu de Loewenstein dans un aspect bronchique fait mettre en place un traitement antituberculeux. Celui-ci, poursuivi pendant 1 an, a amene une guerison rapide en 2 mois. Aucun contage n'a ete retrouve. Conclusion. Tuberculose et mucoviscidose ne sont pas incompatibles, et il est necessaire de penser a une surinfection tuberculeuse et de rechercher les bacilles de Koch dans toute pneumopathie trainante, ne repondant pas au traitement de la mucoviscidose.

The colonization over time of cystic fibrosis patients by Aspergillus fumigatus was investigated using a DNA fingerprinting method. Aspergillus fumigatus isolates collected sequentially for more than one year from six patients with cystic fibrosis were typed by Southern blot hybridization with a repetitive DNA sequence. Each cystic fibrosis patient harbored several strains of Aspergillus fumigatus that were isolated recurrently over time. Isolates collected from a cystic fibrosis patient with aspergilloma displayed the same genotype, suggesting that the infection was due to a single strain. Continuous isolation of the same genotype in another cystic fibrosis patient, however, was not correlated clinically with an Aspergillus infection.

Spintronics is a new direction in electronics. It contains many applications, including spin valves, GMR devices, “spin batteries,” spin-controlled electronic devices, and even spin-controlled wide-bandgap compound semiconductors due to the development of rare-earth-doped nitrides with ferromagnetic properties. Spintronics allows for manipulation of both the spin transport and the charge transported by the electrons. It allows the downscaling to lower device sizes and extension of Moore's law to higher device densities, because it requires less energy to just control the spin of the electron, and the quantum 1/f noise associated with spin control is several orders of magnitude below that associated with conventional electronics. However, the injected spin-polarized current is subject to spin-flip due to various causes. The rate of each of these spin-flip currents is affected by quantum 1/f noise, because of the low-frequency photon emission amplitude that is associated with the elementary spin flip process, no matter what causes the spin flip. As a result, in a spin valve, the leakage current will show 1/f noise. In devices with injection and subsequent control of spin-polarized electrons, the effects obtained will also show this spintronic quantum 1/f noise. For instance, the light output of a spin-controlled LED will exhibit quantum 1/f intensity fluctuations. The present paper calculates the 1/f noise expected in spintronic currents. The spectral density of this fundamental 1/f noise is inherently proportional to the square of the current that is affected by it, but is also inversely proportional to the number of carriers defining this current. The latter dependence can cause the spectrum to be proportional to the first power of the current.

To evaluate the contribution of energy expenditure to the energy imbalance seen in cystic fibrosis patients, resting energy expenditure was measured using open-circuit indirect calorimetry in eight infants with cystic fibrosis, aged 2-7 months (mean, 4), without overt lung disease and in 10 healthy age-matched controls. In both groups, we found close, significant, linear correlations between resting energy expenditure and body weight and between resting energy expenditure and fat-free mass as measured by anthropometry. Cystic fibrosis patients had a 26% increase in resting energy expenditure per kilogram of fat-free mass as compared with controls and a 32% increase in resting energy expenditure as compared with predicted values for fat-free mass. These data from young infants free of clinical symptoms suggest a constitutional metabolic disorder in cystic fibrosis and support the need for early nutritional therapy in cystic fibrosis patients.

Resume Les adenites a mycobacteries atypiques sont observees electivement chez l'enfant de 1 a 3 ans non vaccine par le BCG. Leur siege est cervical, pretragien ou intraparotidien. L'analyse comparee de l'allergie tuberculinique et des tests cutanes aux antigenes de mycobacteries atypiques oriente le diagnostic. L'identification de la mycobacterie a partir de pus de ponction ganglionnaire fait la preuve de l'infection : Mycobacterium scrofulaceum ou avium-intracellulare ou plus rarement kansasii . L'evolution de ces adenites est plus courte et plus simple que celle des adenopathies tuberculeuses. Les medications antituberculeuses sont de peu d'interet. L'exerese chirurgicale des ganglions a des indications limitees.

For imaging and remote sensing applications, the noise of the THz detector must be minimized. The quantum 1/f theory is introduced and used to obtain analytical expressions of noise in n + p diodes, Schottky diode THz detectors and mixers, a new type of suggested MEMS resonator based Thz detectors, QWIPs and bolometers. For the DAR and for THz communications we also consider phase noise in RTD and GaN/AlGaN HFET based THz generators.

Summary The role of rapidly growing mycobacteria (RGM) in pulmonary disease is unclear. We report one case of lung disease caused by RGM in a 6-year-old child with cystic fibrosis. Mycobacterium chelonae was identified and was susceptible only to kanamycin and clarithromycin. The child, who clinically improved with clarithromycin, received treatment for 12 months and negativity of cultures was obtained. Diagnosis of lung disease caused by RGM is based on microbiologic, histologic, radiographic and clinical criteria. The majority of cases are caused by Mycobacterium chelonae abscessus . This organism is uniformly resistant to standard antituberculosis drugs and many other antibiotics, but clarithromycin has excellent activity against it; clinical trials of this newer macrolide are ongoing to evaluate the role of this agent for treatment of M. chelonae abscessus lung disease.

A 14-year-old girl with high fever, dyspnea and bilateral miliary nodules on chest X-ray, developed a rapidly progressive respiratory failure associated with histiocytic hemophagocytosis. Histologic examination of bone marrow biopsy revealed tuberculous granulomas with caseating necrosis. We report a pediatric case in which treatment with extracorporeal lung support and epipodophyllotoxin VP 16-213 was successful.

The aim of this prospective study was to evaluate the consequences of neonatal treatment with a venovenous extracorporeal respiratory assistance.Thirty nine neonates (28 boys) with acute respiratory failure were included. Extracorporeal respiratory assistance consisted of an apnoeic oxygenation with low frequency positive pressure ventilation and extracorporeal membrane CO2 removal through a venous single canula perfusion circuit. The causes of respiratory distress were: 15 meconium aspiration syndrome, 12 respiratory distress syndrome, six hyaline membrane disease, three sepsis, two diaphragmatic hernia, and one post-surgery Mendelson syndrome. The mean duration of mechanical ventilation was 18 days, including 5 days of extracorporeal respiratory assistance. The prospective follow-up included physical examination, chest radiographs, scintigraphy and pulmonary function tests. These tests studied the following parameters: functional residual capacity by helium dilution technique, lung resistance and dynamic lung compliance by the esophageal balloon technique and blood gases with arterialized blood samples.The mean duration of the follow-up was 21.3 months (6 months to 5 years). Results showed in the first year 33% of children with chronic obstructive pulmonary disease and chest (X-ray abnormalities, such as bronchopulmonary dysplasia in 23% of children. Data of pulmonary function test at the end of the first year: lung resistance and functional residual capacity were within limits of predicted values for height, and dynamic lung compliance was slightly decreased; according to the analysis of the functional profile: 31% without abnormality, 41% of obstructive syndrome and 26% with restrictive pattern. Blood gases were normal in 37 children. At the end of the second year, we noticed normal functional residual capacity, an increase of lung resistance while lung compliance was normalized; functional profile was quite different: with a decrease of the number of patients without abnormality (22%) and increase of those with obstructive syndrome (56%).The percentage of abnormalities is high but these are moderate in most cases, especially if we compare with the initial seriousness of the pulmonary pathology. We suggest a regular follow-up to study the respective incidence of pulmonary disease and/or extracorporeal respiratory assistance over these abnormalities.

Since the cloning of the defective gene in cystic fibrosis, much has been learned on the function of CFTR and on the mechanisms regulating its expression. Based on the current understanding of the processes involved in lung disease progression, a number of approaches have been developed using gene therapy and pharmacological agents. Several of these agents have been reported to restitute a function to CFTR with specific mutations. Other molecules act on channels other than CFTR, and may be effective by bypassing CFTR itself. In the present review the various therapeutical strategies currently investigated are discussed.

Cystic fibrosis is characterized by the accumulation of thick viscous purulent secretions. Recombinant human deoxyribonuclease I (rhDNase) breaks down extracellular DNA, which contributes to the increased viscosity of sputum. A multinational, open-label study was conducted in 974 cystic fibrosis patients with moderate lung disease [forced vital capacity (FVC) 40-70% of predicted values] to examine the safety and efficacy of aerosolized rhDNase, 2.5 mg, once daily over a period of at least 12 weeks. Patients were assessed under conditions reflecting routine clinical practice. During rhDNase therapy, at least one respiratory tract infection (RTI) requiring intravenous antibiotics was experienced by 29.5% of patients. Forced expiratory volume in 1 second (FEV1) and FVC were significantly improved from baseline by a mean of 10.5% and 7.2%, respectively. Voice alteration and pharyngitis were the most frequent rhDNase-related adverse events, but only 2% of all patients discontinued treatment due to adverse events. The results obtained were similar to a subanalysis of data from the first 3 months of a placebo-controlled U.S. study. The patients in the present study had a similar frequency of RTIs and improvement in pulmonary function, and reported fewer rhDNase-related and cystic fibrosis-related adverse events than patients in the U.S. study. We conclude that administration of rhDNase is safe, well tolerated, and effective under conditions reflecting routine clinical practice in patients with cystic fibrosis and moderate lung disease.

Gorham's disease usually manifests as diffuse osteolysis but may be complicated with pleural effusion. We describe the case of a 12 year-old boy who had repeated pleural effusions. Radiographs show a mediastinal widening and an interstitial syndrome related to hemolymphangiomatous involvement.

Tuberculosis is rarely seen in patients with cystic fibrosis.A 14-year old female adolescent, regularly followed for a well-tolerated form of cystic fibrosis, developed an acute respiratory infection with consolidation of the left inferior lobe, and no response to the usual antibiotic treatment of cystic fibrosis. Mycobacterium tuberculosis was found in aspirate by fibroscopy, on Loewenstein medium. No familial or social infection contact were identified. Antituberculous chemotherapy with three drugs brought about a prompt improvement of sytemic signs, weight gain, resolution of pulmonary foci and sedation of biological findings referable to inflammation.This case report reminds us that tuberculosis may occur in cystic fibrosis patients. Loewenstein cultures should routinely be made when faced with an unexplainable worsening of the condition.

More than 600 mutations have been identified in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene and are known to cause cystic fibrosis (CF). This large number of mutations makes the search of the molecular defects in CF patients difficult. We have used the techniques of denaturing gradient gel electrophoresis (DGGE) and direct DNA sequencing to detect the mutations in 334 CF chromosomes mostly of French origin. The whole coding sequence of the CFTR gene corresponding to the 27 exons and their exon-intron boundaries was studied. 45 different mutations were identified. This method allowed us to detect the molecular defect in 90.5% of the mutant alleles and to report a novel mutation D979V.

Positive diagnosis of acute bronchopneumopathy in the child is relatively easy, but defining its aetiology is another matter. Criteria to distinguish between pneumopathy of viral or of bacterial origin should be known but are often on the wrong track. Some clinical and radiological pictures, associated with epidemiological data, can also orient toward an infectious agent and should be taken into account. When clinical severity or the background requires precise diagnosis in order to better adapt the treatment, a choice will need to be made among the numerous techniques now available to detect the responsible infectious agent.

Burkholderia cepacia, Stenotrophomonas maltophilia, and Alcaligenes xylosoxidans have been isolated with increasing frequency from the sputum of patients with cystic fibrosis in a pediatric hospital. In 1994-95, 27 of 120 patients were persistently colonized, 17 with Burkholderia cepacia, eight with Alcaligenes xylosoxidans, and five with Stenotrophomonas maltophilia. Genotyping of 220 clinical isolates revealed that most of the Burkholderia cepacia strains were clonally related, suggesting either cross-infection or a common source of exposure. In contrast, neither cross-infection nor a common source of exposure appear to have occurred in the cases of Alcaligenes xylosoxidans or Stenotrophomonas maltophilia.

The pathology of drug-induced pulmonary toxicity in children is poorly understood and probably under-estimated, in the absence of any prospective studies evaluating in a systematic fashion the side effect of medication on the respiratory apparatus. The pulmonary toxicity of thoracic irradiation has markedly receded with more restricted indications for this sort of treatment. Three clinical patterns are most commonly encountered in drug induced lung disease in children: interstitial lung disease, hypersensitivity lung disease and non-cardiogenic pulmonary oedema. The diagnosis is a diagnosis of exclusion and rests on a group of clinical arguments and also on the progress of the disease. Broncho-alveolar lavage rules out infectious disease. Respiratory function tests show non-specific anomalies. A lung biopsy may be indicated. The mechanism of the pulmonary toxicity are associated with disequilibrium of the oxidant/antioxidant and protease/antiprotease system as well as disturbance of the immune response or alteration of the pulmonary matrix by disease of the collagen system. Increased toxicity may be seen in children because of a very significant cumulative dose. The cytotoxic drugs which are most often implicated in causing this are bleomycin, methotrexate, cyclophosphamide and busulfan. Other drugs which are responsible for toxic lung disease are nitrofurantoin, sulfasalazine, D-penicillamine, betalactams, Diphenyl-hydantoin and carbamazepine. Acute post-radiation lung disease is rare. Post-radiation fibrosis is found six months after irradiation and hinders thoraco-pulmonary growth in the child. It is important to assess lung function in all children before any chemotherapy or thoracic irradiation. Cytotoxic drugs are the most common cause of toxic lung disease. This iatrogenic disease requires a multi-discipline approach to ensure the quality of care for these children.

Mucoepidermoïd carcinomas (MEC) are very rare (less than 20 cases reported in the literature) and potentially malignant bronchial gland carcinomas.Three children, two boys (11 and 7 years old) and one girl (5 years old) suffered from respiratory symptoms such as cough, recurrent pneumonia and/or hemoptysis for 2 to 12 months. Bronchial endoscopy showed a mass into the left (two cases), or the right main bronchus (one case). Chest CT scan identified local extension, and lung-associated lesions. Histopathological study concluded to MEC in the three cases. The patients were treated by segmental bronchial resection, completed with left upper lobectomy (two cases), bronchotomy (one case). All the tumor could be removed; there was no metastasis. The outcome was uneventful with a 8 to 24 months follow-up.Bronchial tumors of children must be considered in patients with chronic cough, recurrent pneumonia and/or hemoptysis and require bronchial endoscopy for their diagnosis.

Since 1987, Pseudomonas cepacia has been isolated with an increasing frequency in the expectorants of children with cystic fibrosis followed at the Hôpital d'enfants Armand Trousseau (Paris, France). Colonization by P. cepacia may be responsible for serious secondary infections and rapid deterioration in respiratory function in these patients. Among the 130 children attending our centre, 14 (8 girls and 6 boys) aged 3 to 18, exhibited chronic colonization. 132 isolates, originating from sputum obtained between 1992 and 1994 were studied. Nine biochemical patterns and 6 antibiotic susceptibility patterns at least were defined, therefore exhibiting great polymorphism. Chromosome restriction patterns with Xba I after pulsed field gel electrophoresis enabled 4 pulsotypes to be identified: A, B, C and D. Thirteen patients harboured pulsotypes A, C and D, and 1 patient pulsotype B, the last being quite distinct from the first three. Pulsotypes A, C and D were almost similar, suggesting that closely related strains, probably the same strain, was harboured by 13 of the 14 patients. The origin could be contamination from a single source, or stem from patient-to-patient crossed transmission.

rhDNase (Pulmozyme) is a new agent in the therapeutic strategy for patients with cystic fibrosis. It is one of the first specific treatments aimed at the respiratory tract. It affects the extracellular DNA which is present in abundant quantities in the bronchial secretions of these patients. rhDNase significantly reduces the incidence of infections and improves respiratory function. It should be used as a major treatment in combination with all other treatments in patients over 5 years of age with a vital capacity of at least 40% the theoretical value. It is important to schedule the respiratory exercises as a function of rhDNase intake. The long-term therapeutic benefit remains to be evaluated.

Chronic respiratory failure (CRF) with hypoxia and hypercapnia is the last ineluctable phase in cystic fibrosis (CF). Nasal positive pressure ventilation (NPPV), a non-invasive method, may be given to CF children with CRF, especially to patients accepted for transplantation (T). This method improves ventilatory function by resting the chronically exhausted respiratory muscles, facilitates bronchial drainage by physiotherapy, prevents the exacerbations of the illness and prepares patients for T.NPPV was used in 6 CF patients (mean age 13 years 6 months). One of them was transplanted 15 days later, two of them were accepted for T. All had hypoxia. Five of them had hypercapnia.NPPV was given to four patients for 3 to 14 months. The preliminary results were positive. One patient gained weight, two had more fluid sputum. One patient showed an increase in functional respiratory tests (FRT: PaO2, vital capacity, FEV-1) while these tests were stabilized in the others.NPPV in an effective non-invasive method for use with CF children. It is indicated for CF patients accepted for T and also earlier, for CF patients with CRF in order to prevent acute exacerbations and functional respiratory deterioration.

Among all organ transplantations, those of heart or heart-lung carry the greatest risk of toxoplasmosis. The disease is observed mainly when the donor is seropositive and the recipient seronegative. In these mismatched couples the risk may be as high as 57 percent. Cardiac tissue transplants are responsible for most contaminations. A subclinical serological reactivation can be observed in seropositive recipients. Patent forms are associated with seroconversion in seronegative subjects. Toxoplasmosis is often severe with multivisceral foci; interstitial pneumonia is possible. The serological diagnosis is easy in cases with significant antibody movements, but it may be difficult if the titre is low or stable. The parasitological diagnosis rests on the isolation of toxoplasma in blood, cerebrospinal fluid, bronchoalveolar lavage fluid and cardiac or cerebral biopsy. Immune defence against toxoplasmosis is primarily cellular, with lymphocytosis and inversion of the CD4/CD8 ratio. Macrophages play a crucial role. Interferon-gamma is the major mediator of cellular resistance. In spite of its immunosuppressive action, cyclosporin clearly has an antiparasitic action in vitro and in vivo. A cytomegalovirus infection might facilitate toxoplasma reactivation. Prevention of toxoplasmosis in transplant recipients includes systematic serology of the recipient and, if possible, the donor, detection of mismatched couples and systematic treatment with pyrimethamine of recipients at risk (in seronegative recipients, this drug has reduced the risk from 57 to 14 percent). Cyclosporin should be used as immunosuppressant in preference to other drugs of this kind. Corticosteroids administered in rejections increase the risk of toxoplasmosis.

Extraocular, facial, bulbar and intercostal muscles are frequently affected in juvenile myasthenia gravis, especially during exacerbations. Acetylcholine receptor antibodies are often present in the blood in this type of myasthenic syndrome.A girl presented with an exertional dyspnea at the age of 13 years, that improved after rest. All investigations were negative, except for lung function tests that showed a restrictive pattern. The diagnosis of juvenile myasthenia gravis was finally made at the age of 15 years because of the recurrence of sudden exertional dyspnea and a history of subtle weakness on repetitive movement leading to poor suckling, together with vocal and occasional swallowing difficulties. Dyspnea immediately improved after intravenous injection of 1 mg neostigmine, but the response was transient. No acetylcholine receptor antibody was found and a search for thymoma proved negative. Ambenonium chloride (Mytelase) was effective on clinical exacerbations, but the only improved test after 9 months of treatment was the functional residual capacity.Anticholinesterase drugs must be tried in patients who present exertional dyspnea without bronchopulmonary or cardiac disease on the presumption of myasthenia gravis even when ocular or bulbar manifestations are absent.

In two infants with recurrent lower respiratory tract infections starting within a few weeks of birth, dynamic electromyographic studies of sucking and swallowing evidenced a disorder of lingual and pharyngeal activities responsible for the episodes of aspiration. The central location of the anomaly was demonstrated by the absence of peripheral neuromuscular anomalies and by the presence of impaired blinking reflexes and brain stem potential anomalies. These neurofunctional anomalies improved over time and magnetic resonance imaging failed to disclose and structural anomalies of the central nervous system. The occurrence of the swallowing disorder as an isolated manifestation and its long duration, with follow-ups of 23 months and 4 years, are two unique features in these cases. Neurophysiologic investigations are essential for documenting the neurologic etiology of the swallowing disorders, demonstrating their location above or within the medulla oblongata, and differentiating functional and organic anomalies.

The incidence of asthma in infancy is rising but its clinical and physiological components remain unclear.A total of 24 infants, aged less than 48 months, in whom the first wheezing episode (WE) appeared before the age of 30 months (mean age: 9 months) underwent clinical examination and pulmonary function tests at least 2 weeks after the last WE.The mean WE frequency was 1.1 per month and the mean number of admissions for WE was 1.8. 63% of patients showed symptoms between WE and 50% had an allergic profile. There was no evidence of thoracic distension. Bronchial obstruction (BO) occurred in 71% of patients; among these, BO was distal or generalized in 59% and medium or severe in 47%. 12.5% of patients were hypoxemic at testing. BO was less severe in patients treated with theophylline; it was more frequent (87%) in those with symptoms between WE and/or several admissions, and/or admission to the intensive care unit.This study provides additional evidence that infants presenting with asthma at an early age have severe clinical and physiological profiles.

The value (in terms of decreased numbers of attacks and of hospitalizations for attacks, decreased need for asthma medications, and improved tolerance to allergens) of rush immunotherapy to a mixture of allergens was studied in children with multiple sensitizations and severe asthma (as evaluated on the number of attacks, number of hospitalizations, and dependence on corticosteroids) already receiving optimal medical therapy. Because syndromic reactions are common, rush immunotherapy should be performed in the hospital and premedication with corticosteroids may be warranted in the most severe cases.

Peak-flow measurement increasingly seems to be very useful for routine monitoring of asthma in children. The purpose of this study was to evaluate the reliability and reproductibility of three different peak-flow meters: Miniwright, Vitalograph and Assess. This prospective study was conducted in 100 primary school children aged from 6 to 11 years. In each child, 9 measurements of expiratory peak-flow rate (EPF) were performed with these 3 peak flow meters in a random order. Reproductibility was assessed for each instrument by the greatest divergence observed between the 3 EPF values measured in the same session. Reliability was assessed by comparison between the values obtained with each instrument and theoretical EPF values calculated from a formula which included age, sex and size. Our study validated the reliability and reproductibility of the 3 peak flow meters studied. EPF values were more scattered and less reproductible with Assess, but the difference was not significant.

Between 1977 and 1990, 11 children with carinal bronchogenic cysts were operated in our institution: 8 girls and 3 boys, ranging in age from 1 month to 5 years. All were symptomatic (acute respiratory distress and recurrent bronchiolitis). Chest X-ray showed an unilateral over distension in 10/11 cases. Barium oesophagogram showed a compression in 6/10 cases. Bronchoscopy noticed an extrinsic compression in 10/11 cases and a tracheal and/or bronchial diskinesia in 5/11 cases. The computed tomography showed a low density mass in 4/4 cases. 9 cysts were left-sided and 2 right-sided. Both children underwent a second surgery for a second cyst. 2 pneumonectomies for complete parenchyma destruction were realised. 1 left pulmonary hypoplasia was noticed. A tracheal and/or bronchial diskinesia in post-operative was noticed in 5/6 cases. The clinical and functional respiratory following was good in 10/11 cases. An early surgery treatment is necessary before definitive sequelae.

Compliance with treatment is a crucial factor in the management of asthmatic children which depends on the understanding of the disease and its treatment. The understanding of, and compliance with treatment were evaluated by means of a questionnaire in 50 parents of asthmatic children. 50% of these parents used anti-histamines as maintenance treatment and 30% also used these drugs during attacks. Half the parents knew about the bronchodilator effects of theophylline and B2-agonists. 42% and 30% respectively of the parents thought that the side-effects of theophylline or corticosteroids were few or inexistent; 86% claimed regular attendance to out-patient clinics, but 30% confessed that they had forgotten such drugs as theophylline and antihistamines. 50% took the appropriate therapeutic measures when confronted with a moderate or severe attack of asthma. Each child received 2.3 drugs on average for his or her asthma. This study shows that parents have an insufficient knowledge of asthma treatments, and this may partially explain the poor compliance with therapy as well as the morbidity and mortality associated with childhood asthma.

A series of 27 children (mean age: 12 yrs, 5 mos.) presenting with thoracic sarcoidosis is reported. This series, collected from 1961 to 1988 shows the rarity of the disease at that age. However the low rate of asymptomatic forms (22%) suggests that the frequency of the disease is underestimated, as it is not diagnosed. The histological proof is necessary for the diagnosis. When peripheral lesions available for biopsy are lacking, a liver needle biopsy is helpful (93% of positivity). This study shows the frequency of multivisceral types, the intensity of the macrophagic and lymphocytic alveolitis. The therapeutic indications depend on the comparison of the radiological stage, the results of pulmonary function tests (PFT), those of the bronchoalveolar lavages (BAL) and of the serum granulomatous activity markers, especially concerning angiotensin converting enzyme (ACE). When present at the beginning of evolution, several risk factors lead to use a corticosteroid treatment: age of onset before 4 years, multivisceral involvement, presence of functional pulmonary signs, delayed diagnosis and onset of treatment, impaired respiratory function (especially concerning the alveolo-capillary diffusion), PMN cells greater than or equal to 2% in the initial BAL, and IgG proteins greater than 4 SD. Thus sarcoidosis in children differs from that seen in adults as it has a more marked evolutive tendency and leaves severe sequelae in one third of patients.

Studies of congenital toxoplasmosis in twins confirm the definite role of the placenta in the modalities and mechanism of fetal contamination. In single-chorion twin pregnancies, clinical manifestations are generally identical in both infants. Conversely, twins from double-chorion pregnancies usually have different clinical patterns; occasionally, only one of the twins is affected (1 case). The diagnosis can be ascertained antenatally by sampling blood from each of the fetuses (2 cases). The cases reported herein illustrate some of the diagnostic pitfalls that may lead to inappropriate discontinuation of monitoring and treatment: negative placental studies, absence of specific IgM antibodies, transient fall in IgG antibody titers, delayed fetal contamination after a negative fetal blood study, and need for routine tests for increased CSF albumin levels.

The authors report the case of an intralobar pulmonary sequestration in a newborn presenting congestive heart failure. The clinical symptoms mimicked a persistent ductus arteriosus. Clinical, radiographic and echographic data suggested the diagnosis which was confirmed by the angiography. A surgical treatment was realised at seven weeks consisting in the ligation of the abnormal artery and a right lower lobectomy. This is the 9th case found in the literature. A congestive heart failure in a neonate with normal intracardiac anatomy may suggest a pulmonary sequestration.

We report the follow-up of 13 infants aged 2.5 to 24 months in whom cystic fibrosis disease presented as respiratory distress. All infants received an intensive treatment. Mean clinical, radiological and microbiological follow-up was 3.1 years. Ten children aged 1.5 to 8.5 years are still alive. One of them presents with serious respiratory failure, with a Shwachman score of 50. The Shwachman score is between 85 and 70 for 8 of 13 and 65 for one. The prognosis of this group did not differ from the one usually observed in the disease. It depends partially on early intensive care management and is not altered by mechanical ventilation.

The only available method for quantitative exploration of skin allergy to tuberculin is intradermal injection, since there is no other satisfactory method to evaluate the induration observed. Below 5 mm the induration has no significance. Between 5 and 10 mm it corresponds to an allergic reaction induced by BCG vaccine or by usually inapparent infections due to atypical mycobacteria. A diameter of 10 mm or more suggests either M. tuberculosis infection or allergy to BCG. The intensity of allergic reaction varies under the influence of numerous factors which may be genetic or nutritional, or associated with viral infections, antiviral vaccines and medicinal treatments. Exploring this allergy is of interest on the scores: (1) for epidemiological purposes, to obtain information on the annual risk tuberculosis infection or on the quality of the protection conferred by the vaccine in a given population; (2) for diagnostic purposes, to detect tuberculosis, and especially primary tuberculosis in children; (3) for vaccinal purposes, to determine the limitation of BCG. In subjects who have been vaccinated tuberculosis is rare but remains possible, and in such cases reactions to tuberculin may be difficult or even impossible to interpret.

ENT involvement is very frequent in mucoviscidosis, particularly rhinitis and sinusitis. This prospective study, which spanned from September 1st, 1988 to August 31st, 1989 anc included 27 children with cystic fibrosis of pancreas was carried out with the intent of determining the incidence of the various associated diseases, their bacteriologic profile, and the optimal therapeutic procedure. Less than a child in 5 is symptomless when the nose and sinuses are affected. Polyposis is found to occur in 6/27 cases, and all children have sinus radio-opacities. Ear disease is rare (1/4 of cases) and is manifested by asymptomatic tubal dysfunction with minimal audiometric repercussions. Bacteriologic specimens of sputum and sinus purulent discharge show simultaneous germ positivity (10 times out of 11). Our therapeutic recommendations are based on our own experience as well as literature data, and are, in our opinion, only relevant for children with clinical signs of disease, as opposed to advocating systematic treatment of sinus foci found on X-ray.

The short term prognosis of the esophageal atresia has been improved by the progress of diagnosis and surgical techniques. The long term prognosis still depends upon the occurrence of bronchopulmonary complications. Having investigated fourteen cases and a review of the literature, the authors studied the cause of these respiratory complication. Two factors seem to play an important role: the gastroesophageal reflux and the tracheomalacia. This has important therapeutical implications: treatment of the gastro-esophageal reflux and long term respiratory kinesitherapy. The authors suggest for these patients a management plan over several years.