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B Housset

Publications and source records attributed to B Housset.

At least 37 records · Page 2Linked to original sources
PubMed1999

Evaluation of clinical case definitions of influenza: detailed investigation of patients during the 1995-1996 epidemic in France.

Using clinical predictors, we evaluated clinical case definitions of influenza during the 1995-1996 outbreak in France. Thirty-five general practitioners collected virological specimens and clinical data. Predictors of influenza virus infection were selected with logistic regression models. The results varied with the influenza virus subtype: temperature of >38.2 degrees C, stiffness or myalgia, rhinorrhea, and cough were predictive of influenza A/H3N2, whereas fatigue, lacrimation or conjunctival injection, and the absence of stiffness or myalgia were predictive of influenza A/H1N1. On the basis of this analysis and data from the literature, 12 clinical case definitions were evaluated for their abilities to diagnose influenza virus infection. They were associated with positive predictive values of 27% to 40% and negative predictive values of 80% to 91%. We conclude that focused studies evaluating clinical case definitions of influenza with use of subsets of patients should accompany population-based disease surveillance for optimal estimates of the disease burden associated with influenza epidemics.

Disease Outbreaks↗
PubMed1999

[Asbestosis].

Explore the source record for details and available documents.

Asbestos↗
PubMed1999

[Asbestos-related occupational lung diseases. Role of the pneumology unit in screening and compensation].

The application of new decrees concerning the protection of individuals against sanitary risks linked to the various possible expositions to asbestos dusts is leading to a growing involvement of pulmonologists in diagnosis procedures not only for active workers regularly examined via the occupational medicine healthcare system, but also for those who are no longer, the unemployed or retired previously exposed to asbestos fibres. The present chapter presents and comments the revised guidelines about the compensation procedures for occupational diseases, and provides useful recommendations for establishing the records leading to their medical assessment. It emphasises the importance of a close cooperation between pulmonologists and radiologists in order to avoid radiation overdosing, which could increase the risk of lung cancer, as much as possible.

Asbestos↗
PubMed1999

[Biological markers and exposure to asbestos].

Review of published studies clearly demonstrates the absence of value of the CEA, CYFRA21-1 and NSE biomarkers, either alone or combined, for the screening of lung cancer. So far, diagnostic value of other biomarkers, such as p53 tumor suppressor gene or the detection of antibodies raised against receptors encoded by oncogene or against p21 protein (encoded by K-ras oncogne) remains speculative. This justifies that efforts should be reinforced in this field. Similarly, further studies are needed for biomarkers indicative of individual susceptibility to asbestos-related cancers, particularly in the field of P450 cytochromes or glutathione-S-transferase.

Asbestosis↗
PubMed1998

Antioxidant activity in alveolar epithelial type 2 cells of rats during the development of bleomycin injury.

Bleomycin (BLM) induces lung inflammation and subsequent fibrosis in human and in animal models. Alveolar epithelial type 2 cells (T2 cells) are known to play a crucial role in the repair process after BLM injury. We hypothesized that resistance of T2 cells to BLM-damage was associated with an increase in their antioxidant system activity. We developed an animal model of lung lesions preceding fibrosis, using daily intraperitoneal administration of BLM (1.5 mg/day over 7 and 14 days). We observed a body weight stabilization in BLM-treated rats from the third day. After 14 days of BLM treatment, the number of cells recovered by bronchoalveolar lavage was significantly increased (p < 0.05), with a dramatic increase (p < 0.01) in the percentage of neutrophils associated with a decrease in macrophage percentage (p < 0.01) No evidence of fibrosis was seen by microscopic studies at this time. However, T2 cells in 14-day-treated rats were swollen with enlarged lamellar inclusion bodies. Biochemical study of freshly isolated T2 cells displayed a significant decrease of lactate dehydrogenase (LDH) released by these cells when isolated from 14-day-treated rats as compared with 7-day. By contrast, BLM induced an increase in superoxide dismutase (SOD) and glutathione peroxidase activities. Cell content of glutathione was decreased and gamma-glutamyl transpeptidase activity was markedly increased. These results show that BLM induces changes in the antioxidant system of T2 cells, particularly in the glutathione system.

Animals↗
PubMed1998

Polycythemia impairs vasodilator response to acetylcholine in patients with chronic hypoxemic lung disease.

To investigate whether polycythemia associated with chronic hypoxemic lung disease (CHLD) increases vascular resistance by altering endothelium-derived nitric oxide (NO), we examined the responses to acetylcholine (ACh) infusions (5, 10, and 15 mg/min) on hemodynamics and gas exchange in 21 patients with CHLD of varying severity. Patients were classified into two groups based on whether their hemoglobin (Hb) level was less or greater than 15.5 g/dl. In the normocythemic patients (Hb = 13.6 +/- 0.3 g/100 ml, n = 10), ACh decreased pulmonary artery pressure (Ppa) from 30 +/- 2 mm Hg 26 +/- 2 mm Hg (p < 0.01); pulmonary vascular resistance (PVR), from 5.1 +/- 0.4 U/m2 to 3.4 +/- 0.3 U/m2 (p < 0.001); systemic arterial pressure (Psa), from 111 +/- 4 mm Hg to 108 +/- 4 mm Hg (p < 0.05); and systemic vascular resistance (SVR), from 27 +/- 2 U/m2 to 22 +/- 2 U/m2 (p < 0.01); and also increased the cardiac index (CI), from 3.8 +/- 0.2 to 4.7 +/- 0.3 L/min/m2 (p < 0.001). PaO2 fell from 59 +/- 3 mm Hg to 48 +/- 3 mm Hg (p < 0.001) whereas venous admixture (Qs/Qt) rose from 32 +/- 4% to 44 +/- 4% (p < 0.01). In contrast, in patients with polycythemia (17.7 +/- 0.5 g/100 ml, n = 11) ACh failed to produce any changes in PaO2 (49 +/- 2 mm Hg versus 51 +/- 2 mm Hg, p = NS), Ppa (34 +/- 1 mm Hg versus 33 +/- 1 mm Hg, p = NS), PVR (6.7 +/- 0.9 U/m2 versus 6.9 +/- 0.8 U/m2, p = NS) or Psa, but slightly increased the CI, from 3.6 +/- 0.3 L/min/m2 to 3.9 +/- 0.3 L/min/m2 (p < 0.01), and Qs/Qt, from 40 +/- 4% to 45 +/- 3% (p < 0.05). In the 21 patients, negative correlations with Hb concentrations were found for ACh-induced changes in PVR (r = -0.57, p < 0.01), Ppa (r = -0.46, p < 0.01), CI (r = -0.5, p < 0.05), PaO2 (r = -0.79, p < 0.01), and Qs/Qt (r = -0.79, p < 0.01). In the six polycythemic patients who received isovolemic hemodilution, with a decrease in Hb concentration from 18.6 +/- 0.9 g/dl to 15.3 +/- 0.3 g/dl as a result, infusion of ACh, which was without effect before hemodilution, caused decreases in Ppa from 28 +/- 1 mm Hg to 23 +/- 1 mm Hg (p < 0.05) and in PVR from 5.7 +/- 0.8 U/m2 to 3.6 +/- 0.5 U/m2 (p < 0.02), as well as an increase in CI from 3.4 +/- 0.4 L/min/ m2 to 4.1 +/- 0.4 L/min/m2 (p < 0.05). In contrast to ACh, inhaled NO (40 ppm) induced pulmonary vasodilation in both the normocythemic and polycythemic groups. Our results show that high hematocrit (Hct) levels inhibit endothelium-dependent vasodilation in response to ACh in patients with CHLD, possibly through inactivation of endothelial-derived NO by Hb.

Acetylcholine↗
PubMed1998

CPAP titration by an auto-CPAP device based on snoring detection: a clinical trial and economic considerations.

This study aimed to assess the ability of an auto-nasal continuous positive airway pressure (nCPAP) device (REM + auto; NPBFD, Nancy, France) to predict the optimal constant nCPAP level. The apnoea/hypopnoea detection facility of the auto-nCPAP device was deliberately disabled and nasal mask pressure vibration detection was the only mode of pressure setting. The auto-nCPAP device was tested on 10 previously untreated patients with obstructive sleep apnoea during a single night, with ambulatory polysomnography performed in a conventional hospital room; the efficacy of the fixed pressure determined by the auto-nCPAP device was assessed by an ambulatory full polysomnography 2 weeks after the initiation of treatment at home. The fixed nCPAP pressure was effective (apnoea/hypopnoea and arousal indices <10 events x h(-1)) in all but two of the 10 patients studied. When the fixed nCPAP pressure was increased by 2 cmH2O in these two patients, sleep and respiration were normalized. Since only 12 ambulatory polysomnographic recordings were used to determine the effective nasal continuous positive airway pressure level, and as the device restored normal breathing and sleep in all 10 patients, it was concluded that this method of nasal continuous positive airway pressure titration may improve cost-effectiveness and reduce waiting lists in sleep laboratories.

Adult↗
PubMed1998

Routine use of granulocyte colony-stimulating factor is not cost-effective and does not increase patient comfort in the treatment of small-cell lung cancer: an analysis using a Markov model.

PURPOSE: The clinical indications and economic consequences of human granulocyte colony-stimulating factor (G-CSF) prescription during small-cell lung cancer (SCLC) chemotherapy remain controversial. The aim of this study, based on a Markov model, was to assess the impact of routine G-CSF use in the treatment of SCLC on costs and patient comfort. Markov models allow the modeling SCLC chemotherapy, in which the risk of febrile neutropenia (FN) is continuous over time and may occur more than once. PATIENTS AND METHODS: We used a Markov model to compare three strategies: a chemotherapy dose reduction after FN and nonuse of G-CSF ("never" strategy), secondary use of G-CSF ("CSF if FN" strategy) and primary use of G-CSF ("systematic CSF" strategy). Model baseline probabilities were based on a review of medical records for all patients (n = 39) treated for SCLC in our unit during 1993 (when G-CSF was not used) and on published reductions in the incidence of FN obtained by using G-CSF. Two different types of rewards were used: a cost-utility scale that took into account the costs of FN (CFN) episodes and G-CSF (CCSF) courses; and a comfort-utility scale that took into account the discomfort of FN and G-CSF therapy. Costs were analyzed from the health care payer's perspective and utilities were assessed prospectively in standardized interviews with treated SCLC patients. RESULTS: The never strategy was the least costly ($4,875 [United States] versus $5,816 and $7,690 for CSF if FN and systematic CSF) and gave the highest comfort value (378 U v 365 and 327 for CSF if FN and systematic CSF). Sensitivity analyses showed that the never strategy remains the less costly when the probability of a first FN episode was less than 49%, the probability of FN recurrence was less than 60%, or the CFN was less than $6,077, or the CCSF was greater than $863. In terms of patient comfort, the never strategy was the best choice, except for patients who considered that a course of G-CSF caused little or no discomfort, whether or not it prevented FN. CONCLUSION: Routine use of G-CSF during SCLC chemotherapy is not justified by clinical benefits, improved patient comfort, or economic considerations.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

[Thiamine deficiency. A cause of cardiac insufficiency not to be ignored].

Thiamine deficiency is one of the classical causes of high out put for heart failure. Deficiency of this vitamin may be nutritional or secondary to alcoholic intoxication. We felt it would be interesting to describe a typical case of cardiac beriberi in order to recall the clinical presentation and the pathophysiology.

Acidosis↗
PubMed1998

[Asbestos-associated occupational lung diseases. Role of the pneumology unit in screening and compensation].

The application of new decrees concerning the protection of individuals against sanitary risks linked to the various possible expositions to asbestos dusts is leading to a growing involvement of pulmonologists in diagnosis procedures not only for active workers regularly examined via the occupational medicine healthcare system, but also for those who are no longer, the unemployed or retired previously exposed to asbestos fibres. The present chapter presents and comments the revised guidelines about the compensation procedures for occupational diseases, and provides useful recommendations for establishing the records leading to their medical assessment. It emphasises the importance of a close cooperation between pulmonologists and radiologists in order to avoid radiation overdosing, which could increase the risk of lung cancer, as much as possible.

Asbestos↗
PubMed1997

[Diagnosis of pleurisy].

Diagnosis of pleural effusion, suggested by chest pain or dyspnea, is assessed by physical examination, chest X-ray sometimes completed by other imaging techniques, and mainly by thoracentesis. Thoracentesis is mandatory for the diagnostic of pleural effusion as three diagnosis are associated with an emergency treatment: pulmonary embolism; hemothorax; empyema. If the fluid is a transudate, no further invasive studies are necessary. If the cause of pleural exsudat cannot be established by a careful history, physical examination and fluid analysis, generally closed pleural biopsy should be done, followed, in absence of an established diagnosis, by thoracoscopy. At this time, less than 10% of the cases remain without explanation, leading to a careful follow-up of patients since a carcinomatous lesion may develop in 1/3 of them.

Biopsy, Needle↗
PubMed1997

[Surgical pulmonary biopsies in patients with HIV infection: results apropos of a series of 21 cases].

This retrospective study reports the results of surgical lung biopsies in 21 patients infected by HIV. Diagnostic was assessed by surgical lung biopsies in 66% of cases with a 5% immediate post-operative mortality and a 80% survival rate after one month. Therapeutic management was modified in 38% of cases. These results are in concordance with previously published literature and emphasize that such a procedure should only be performed after other diagnostic procedures, including at least a bronchial endoscopy associated to a BAL and/or transbronchial biopsies.

Adult↗
PubMed1997

Influenza and influenza-like illness in general practice: drawing lessons for surveillance from a pilot study in Paris, France.

BACKGROUND: There are two types of inflenza surveillance techniques: qualitative laboratory-based surveillance and quantitative medical practice-based surveillance. The former is of great importance in isolating new strains of the virus, which helps in the decision-making process concerning the composition of the vaccine, and the latter provides estimates of morbidity, mortality or economic impact as a result of infection from the influenza virus. Rapid methods such as immunoflourescence (IF) or immunocapture assays (ICA) are now available for diagnosis of influenza infections. However, little is known about the use of these methods for influenza surveillance purposes. AIMS: To evaluate the feasibility of a rapid influenza diagnosis in ambulatory conditions, and to investigate the therapeutical outcomes of patients suffering from influenza-like illness (ILI) in relation to the virological diagnoses. METHOD: During the 1994-1995 influenza season, 130 patients presenting with ILI symptoms (< 36 hours) to 33 general practitioners (GPs) were included in a prospective study. Two nasal swabs and one throat swab per patient were collected and sent to the laboratory within 12 hours. Information concerning therapeutical outcomes was recorded during examination. Specimens were analysed using the immunofluorescence (IF) method and antigen immunocapture assay (ICA). RESULTS: Sixteen influenza A (12%) and 19 influenza B (15%) infections were diagnosed. The overall rate of influenza positive specimens was 17% in the pre-epidemic period and 31% during the epidemic (P = 0.1). The rates of usable specimens for IF assay, nasal ICA and throat ICA were 46%, 100% and 99% respectively. The combination of these three collections ensured a highly sensitive influenza virological diagnosis. There were no differences in therapeutical outcomes between the influenza positive and negative cases. The GPs prescribed antibiotics in 60% of the cases for a mean duration of 7 days (+/- 1.2). The mean duration of sick leave was 3.4 days (+/- 1.6). Twelve patients (four influenza positive, eight influenza negative) had been vaccinated at the beginning of the winter. The practitioner's intuition concerning 'which patient should be tested for influenza virus' did not prove useful in improving the aptness of virological diagnoses in the field of influenza surveillance. CONCLUSION: The only way to estimate the true impact of influenza is to carry out a systematic virological sampling based on a sensitive clinical definition and using sensitive laboratory methods.

Adult↗
PubMed1996

Oxidant-antioxidant balance in alveolar macrophages from newborn rats.

An oxidant-antioxidant imbalance in neonatal alveolar macrophages (AMs) may contribute to the increased susceptibility to lung injury described in the neonatal period. We therefore evaluated oxygen radical production by rat AMs at various postnatal ages, and measured in parallel cellular antioxidant enzyme activities. AMs were obtained by bronchoalveolar lavage from rats aged < 24 h, 21 days and 5 weeks, and results were compared to those obtained with adult rat AMs. Intracellular production of oxygen radical species, estimated fluorometrically using 2',5'-dichlorofluorescein diacetate as the substrate, was significantly reduced in neonates as compared with adults, both in the presence and in the absence of cell stimulation with phorbol myristate acetate (PMA) or opsonized zymosan. A similar pattern was observed for the extracellular release of oxygen radical species, evaluated by lucigenin-enhanced chemiluminescence (CL) or peroxidase-catalysed CL oxidation of luminol: peak CL values measured after cell stimulation with PMA or opsonized zymosan remained significantly lower for AMs from newborn rats than for AMs from adults. By contrast, high values for antioxidant enzyme activities (superoxide dismutase and glutathione peroxidase) in AMs were demonstrated in newborns as compared to adults. We conclude that high antioxidant activity in rat AMs after birth may be at least partly responsible for the low production of oxygen metabolites observed during the same period.

Aging↗
PubMed1996

BAL in children: a controlled study of differential cytology and cytokine expression profiles by alveolar cells in pediatric sarcoidosis.

STUDY OBJECTIVE: The development of BAL in children for both research and clinical purposes has been limited so far by the difficulty in establishing reference values. The aim of the study was (1) to define composition of BAL cellular components in control children and to evaluate the ability of these cells to express various cytokines, and (2) to study modifications of differential cytology and BAL cell cytokine responses in children with interstitial lung disorders. POPULATIONS AND METHODS: Two groups were investigated: a control group of 16 children who were concluded to be free of parenchymal lung disease after complete pulmonary investigation, and a group of 11 children with pulmonary sarcoidosis. Differential cytology was evaluated by standard techniques. BAL cell cytokine expression was studied at the level of messenger RNA (mRNA) by reverse transcription-polymerase chain reaction (RT-PCR) methods. RESULTS: In the control group, differential cell counts appeared to be similar to values reported in adult populations with normal distribution of the data and no influence of age. In this group, no transcripts for interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), IL-6, and transforming (correction of tranforming) growth factor-beta (TGF-beta) could be detected. In children with sarcoidosis, different profiles of IL-1beta, TNF-alpha, IL-6, and TGF-beta expression were individualized which seemed to be related to the activity and/or severity of the disease, IL-6 and TGF-beta mRNA being observed only in the more severe forms. CONCLUSION: These data provide information on BAL cell number and function in children. Characterization of BAL cytokine expression patterns during the course of interstitial lung diseases in children may be of great interest for evaluation of disease activity and/or severity and therefore for planning of therapy.

Actins↗
PubMed1996

[Diagnostic strategies of pulmonary pneumocystis infection in patients with HIV infection. Decision analysis and medico-economic consequences].

P. carinii pneumonia is one of the most frequent opportunistic infections in HIV-infected patients. Clinical and radiological manifestations are non-specific and reference diagnostic procedure remains broncho-alveolar lavage which is costly and invasive. Alternative diagnostic strategies have been proposed. We report here our experience as well as literature date in this field with the purpose to show the usefulness of decision analysis techniques in choosing an optimal cost-effective strategy.

AIDS-Related Opportunistic Infections↗
PubMed1995

[Clinical aspects and outcome of COPD].

Chronic obstructive pulmonary disease (COPD) is a frequent disease which is too often diagnosed when already severe. Major known risk factors are tobacco smoking, occupational exposure, and severe respiratory infections during childhood. Diagnostic should be evoked on functional non specific symptoms: chronic cough and sputum, progressive dyspnea. Some physical signs, correlated with the degree of airway obstruction, may be more specific but their diagnostic value remains to be assessed. These signs reflect distension of the chest as well as airway obstruction: pursed lips breathing, increased expiration duration, Hoover and Campbell signs, inspiratory contraction of scalen muscles. COPD results over years in chronic respiratory insufficiency and evolution is associated with episodes of bronchial and parenchymal infections as well as pulmonary emboli which are particularly frequent in these patients.

Adult↗