[Influence of the COVID-19 pandemia on the ophthalmologic emergency department in the Toulouse University Hospital during the first lockdown from March the 17th to May the 10th of 2020]

INTRODUCTION

We conducted this study to assess the impact of the COVID-19 pandemic and the lockdown in France from March 17, 2020 to May 10, 2020, on the ophthalmic emergency department at Toulouse University Hospital, compared to the period from March 2 to March 16, 2020.

MATERIALS AND METHODS

This was a retrospective observational study, conducted in the ophthalmic emergency department of Toulouse University Hospital. We included the patients presenting to the emergency department from March 2 to May 10, 2020. We recorded age, sex, day of visit, time until care was received, past ocular history, outpatient or inpatient status, final diagnosis and its severity, outpatient or inpatient disposition, and medical or surgical treatment after the emergency department visit.

RESULTS

We found a substantial decrease in the number of patients per day, mostly during the first month of the lockdown: 44 patients per day before the lockdown compared to 23 patients per day during the first month, followed by 38 patients per day for the second month of lockdown; more patients visiting promptly; and elderly patients represented a higher proportion of patients.

CONCLUSION

The first lockdown in France due to the COVID-19 pandemic had an impact on the Toulouse ophthalmic emergency department, especially concerning the number of patients per day; this study helps to assess individual behavior in this context of a public health crisis.

Doramectin efficacy against Psoroptes ovis in sheep: Evaluation of pharmacological strategies

The aims of this study were to evaluate the efficacy of two injectable formulations of doramectin (DRM) against Psoroptes ovis in sheep infested under controlled experimental conditions and to characterize the DRM plasma disposition kinetics in the infested animals. To this end, sheep were experimentally infested with a P. ovis strain from a farm with a history of treatment failure, and then treated either with DRM 1% (traditional preparation) on days 0 and 7 or with DRM 3.15% (long-acting formulation) on day 0. The efficacy of each treatment was calculated by counting live mites in skin scrapings. Plasma samples were obtained from each animal and DRM concentrations were measured by HPLC. After the two doses of DRM 1%, the maximum efficacy (98.8%) was reached on day 28, whereas after the single dose of DRM 3.15%, the maximum efficacy (100%) was reached on day 35 and ratified on day 42. The long-acting formulation allowed obtaining higher exposure and more sustained concentrations of DRM than the traditional preparation. Although both DRM formulations studied were effective according to international protocols, they did not reach 100% effectiveness in the time required for approved pharmaceutical products against sheep scab, according to Argentine regulations.

Large number of imported chikungunya cases in mainland France, 2014: a challenge for surveillance and response

During the summer of 2014, all the pre-requisites for autochthonous transmission of chikungunya virus are present in southern France: a competent vector, Aedes albopictus, and a large number of travellers returning from the French Caribbean islands where an outbreak is occurring. We describe the system implemented for the surveillance of chikungunya and dengue in mainland France. From 2 May to 4 July 2014, there were 126 laboratory-confirmed imported chikungunya cases in mainland France.

[Transurethral resection (TUR) in saline plasma vaporization of the prostate versus standard TUR of the prostate: an economic evaluation]

OBJECTIVE

To evaluate and compare the hospital costs of the transurethral resection in saline plasma vaporization of the prostate (TURis-PVP) and the standard TUR of the prostate (TURP).

BACKGROUND

their efficiency and short terms outcomes are similar.

PATIENTS AND METHODS

In an observational retrospective and monocentric study, 86 consecutive patients with benign prostatic enlargement (BPE) secondary to benign prostatic hyperplasia (BPH) were enrolled in two non randomized groups. TURP was performed in 44 cases and TURis-PVP in 42 cases. Patients with prostate cancer, urethral stenosis or bladder neck stenosis were not included. Hospital costs with a 3-month follow-up were measured using the database and hospital cost accounting system of the Medical Information Department.

RESULTS

Patients from both series had similar preoperative characteristics concerning the age, ASA score, urologic history, and antithrombosis treatments. Catheterization period, complications and rehospitalisation rates were similar. With TURis-PVP, prostatic volume was larger (60±24mL vs. 42±16mL; P<0.05), hospital stay was shorter (4.0±2.8days vs. 4.4±2.1days; P<0.05), single-used materials costs were higher (332±64€ vs. 40±18€; P<0.05). The costs of the first hospitalization were 3721±843€ with TURis-PVP and were 3712±880€ with TURP (P=0.14). Global costs with a 3-month follow-up were 3867±1104€ with TURis-PVP and were 4074±1624€ with TURP (P=0.53).

CONCLUSION

In this study, the costs for the hospital are lightly higher in TURis-PVP, due to single use systems, but there is no significant difference for global costs between TURP and TURis-PVP with a 3-month follow-up difference for the health care system.

[When the pupil becomes the teacher]

OBJECTIVE

To evaluate the theoretical teaching provided to ophthalmology residents in Toulouse during the 2006-2007 academic year using the PowerVote(®) system. PUPILS AND METHOD: This was a prospective study concerning all ophthalmology residents in Toulouse. Classes were given by the house doctors and senior registrars as PowerPoint presentations lasting about 45 min. Just before each lecture, the house doctors took a 5 min test comprising five multiple choice questions. There were two lectures per month on average. One month after the course of lectures ended, the course as a whole was evaluated using the PowerVote(®) tool, on objectives given to the house doctors in advance. The teaching concerned the macula.

RESULTS

Ten residents took part in the final evaluation in 2007. The residents who had given lectures obtained significantly better results, not only in the initial test but also in the final one.

DISCUSSION

Teaching can take many forms. We evaluated teaching by the students themselves. The more involved a house doctor was in teaching, the better he remembered the lesson.

CONCLUSION

Giving a theoretical lecture enables residents to reach a higher level, which is further improved if they are involved in the teaching. The use of PowerVote(®) is an interesting pedagogical tool.

[Results of 125-iodine seed implant with preplanning system in 250 patients with prostate cancer]

INTRODUCTION

We review the experience with prostate carcinoma patients treated with permanent implants of 125-I seeds and the outcome eight years after the beginning of this technique.

MATERIAL AND METHODS

From 2002 to 2007 we have performed 250 implants with LDR brachytherapy with RapidStrand(®) and preplanning system. Mean age was 68 (49-78). Mean PSA was 7.32 (2.31 - 14.6). T1-T2a was the stage in 98%, and Gleason ≤ 6 in 96%. Low risk cases were 81% and intermediate risk 19% (ten of them received 46 Gy EBRT). Hormonal treatment was used in 42%.

RESULTS

With a mean follow-up of 48 months, 14 patients (5.7%) showed biochemical failure (BF). Eleven patients (4.5%) with theoretical BF were observed and PSA decreased without treatment. Actuarial PSA relapse-free survival at 5 years was 91%, (92% low risk, 86% intermediate cases), and 92% vs 81% with PSA <10 vs >10 (p<0.05). Rectum complications were G2 in 0.6%. A urinary catheter was necessary in 6.5%. Sexual function was conserved in 60%. Mean V100 was 89% and D90 143 Gy.

CONCLUSION

The outcome of patients with low risk prostate carcinoma treated with I-125 seed is very good with very low complications rate. Cases with PSA bounces should be controlled before starting a salvage treatment.

Nationwide outbreak of Salmonella serotype Kedougou associated with infant formula, Spain, 2008

On 5 August 2008, the National Centre of Microbiology in Madrid, Spain, notified an increase in Salmonella Kedougou isolations compared to 2007, with 21 cases including 19 children under one year of age. Active case finding and a matched case-control study were carried out to confirm this increase, identify source, transmission mode and risk factors in order to implement control measures. Cases were defined as any child under one year of age with S. Kedougou isolated since 1 January 2008, and were matched for age, sex, medical practitioner and diagnosis week with controls who were selected among patients of the cases' medical practitioners. An ad hoc questionnaire was completed for cases and controls and a univariate analysis was conducted to identify risk factors. We found 42 isolates from 11 of the 19 Spanish Regions. Completed questionnaires were available for 39 of 42 patients identified; 31 were children under one year of age and fulfilled the case definition. The median age of the 31 cases was 4.3 months and 13 were male. Main symptoms were diarrhoea (n=31) and fever (n=13). Ten cases required hospitalisation. All 31 cases had consumed infant formula milk of Brand A which was associated with illness in the univariate analysis (exact matched odds ratio: 74.92; 95% confidence interval: 12.89-∞). All patient isolates showed indistinguishable pulsed-field gel electrophoresis and antimicrobial susceptibility patterns. Five milk samples from three cases' households were negative for Salmonella. Our results suggest that Brand A was the transmission vehicle of S. Kedougou in the outbreak that occurred in Spain between January and August 2008. Food safety authorities recalled five batches of Brand A milk on 26 August 2008. No further cases have been detected as of 15 September 2009.

Nationwide outbreak of Salmonella serotype Kedougou associated with infant formula, Spain, 2008

On 5 August 2008, the National Centre of Microbiology in Madrid, Spain, notified an increase in Salmonella Kedougou isolations compared to 2007, with 21 cases including 19 children under one year of age. Active case finding and a matched case-control study were carried out to confirm this increase, identify source, transmission mode and risk factors in order to implement control measures. Cases were defined as any child under one year of age with S. Kedougou isolated since 1 January 2008, and were matched for age, sex, medical practitioner and diagnosis week with controls who were selected among patients of the cases' medical practitioners. An ad hoc questionnaire was completed for cases and controls and a univariate analysis was conducted to identify risk factors. We found 42 isolates from 11 of the 19 Spanish Regions. Completed questionnaires were available for 39 of 42 patients identified; 31 were children under one year of age and fulfilled the case definition. The median age of the 31 cases was 4.3 months and 13 were male. Main symptoms were diarrhoea (n=31) and fever (n=13). Ten cases required hospitalisation. All 31 cases had consumed infant formula milk of Brand A which was associated with illness in the univariate analysis (exact matched odds ratio: 74.92; 95% confidence interval: 12.89-infinity). All patient isolates showed indistinguishable pulsed-field gel electrophoresis and antimicrobial susceptibility patterns. Five milk samples from three cases' households were negative for Salmonella. Our results suggest that Brand A was the transmission vehicle of S. Kedougou in the outbreak that occurred in Spain between January and August 2008. Food safety authorities recalled five batches of Brand A milk on 26 August 2008. No further cases have been detected as of 15 September 2009.

Alveolar fibroblasts in acute lung injury: biological behaviour and clinical relevance

Although fibroblasts are key cells in the lung repair/fibrosis process, their characteristics are poorly studied in acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). The aims of our study were to: 1) determine the biological behaviour of alveolar fibroblasts during ALI; and 2) to evaluate the clinical relevance of positive alveolar fibroblast culture from patients with ALI/ARDS. Cells were cultured from bronchoalveolar lavage (BAL) obtained from 68 critically ill, ventilated patients: ALI n = 17; ARDS n = 31; and ventilated controls n = 20. Patients were followed for 28 days and clinical data was recorded. We studied proliferation, migration and collagen-1 synthesis capacities of fibroblasts. Cells expressing fibroblast markers were cultured from BAL obtained in six (35%) ALI patients and six (19%) ARDS patients, but never from ventilated controls. Alveolar fibroblasts exhibited a persistent activated phenotype with enhanced migratory and collagen-1 production capacities, with hyporesponsiveness to prostaglandin E(2) compared to normal lung fibroblasts (p< or =0.04). Positive fibroblast culture was associated with both an increased collagen-1 concentration and monocyte/macrophage percentage in BAL fluid (p< or =0.01), and with a reduced duration of mechanical ventilation (p<0.001). We conclude that activated alveolar fibroblasts can be cultured either in ALI or ARDS and that their presence might reflect the initiation of the organising phase of ALI.

Altered Nrf2/Keap1-Bach1 equilibrium in pulmonary emphysema

BACKGROUND

Oxidative stress, resulting from the increased oxidative burden and decreased level of antioxidant proteins, plays a role in the pathophysiology of smoking-related pulmonary emphysema. Expression of several antioxidant proteins, such as heme oxygenase-1 (HO-1), glutathione peroxidase 2 (GPX2) and NAD(P)H:quinone oxidoreductase 1 (NQO1), results from an equilibrium created by positive or negative regulation by the transcription factors Nrf2, Keap1 and Bach1, respectively. However, whether the expression of these transcription factors is altered in emphysema and could account for decreased expression of antioxidant proteins is not known. A study was undertaken to investigate the expression and subcellular localisation of Nrf2, Keap1 and Bach1 as potential regulators of HO-1, GPX2 and NQO1 in alveolar macrophages, a key cell in oxidative stress, in lung surgical specimens from non-smokers without emphysema and smokers with and without emphysema.

METHODS AND RESULTS

Western blot, immunohistochemical and laser scanning confocal analysis revealed that the Nrf2 protein level decreased significantly in whole lung tissue and alveolar macrophages (cytosol and nucleus) in patients with emphysema compared with those without emphysema. Conversely, Bach1 and Keap1 levels were increased in patients with emphysema. These modifications were associated with a parallel decrease in the expression of HO-1, GPX2 and NQO1 at the cellular level, which was inversely correlated with airway obstruction and distension indexes, and increased macrophage expression of the lipid peroxidation product 4-hydroxy-2-nonenal. Silencing RNA experiments in vitro in THP-1 cells were performed to confirm the cause-effect relation between the loss of Nrf2 and the decrease in HO-1, NQO1 and GPX2 expression. Nrf2/Keap1-Bach1 equilibrium was altered in alveolar macrophages in pulmonary emphysema, which points to a decreased stress response phenotype.

CONCLUSIONS

This finding opens a new view of the pathophysiology of emphysema and could provide the basis for new therapeutic approaches based on preservation and/or restoration of such equilibrium.

Modulation of bleomycin-induced lung fibrosis by serotonin receptor antagonists in mice

Serotonin (5-hydroxytryptamine; 5-HT) is known to increase proliferation and collagen synthesis by fibroblasts. Two receptor subtypes, 5-HT2A and 5-HT2B, have been shown to play the most important roles in the lung. In the present study, the role of serotonin in lung fibrosis was investigated using the bleomycin mouse model. Serotonin concentrations in lung homogenates increased significantly over the time course of bleomycin-induced fibrosis, with a maximum at day seven. The expression of serotonin receptors 5-HT2A and 5-HT2B increased in the lung after bleomycin treatment, as assessed by PCR, specific binding and immunohistochemistry. Blockage of 5-HT2A receptors by ketanserin and 5-HT2B receptors by SB215505 reduced bleomycin-induced lung fibrosis, as demonstrated by reduced lung collagen content and reduced procollagen 1 and procollagen 3 mRNA expression. Serotonin antagonists promoted an antifibrotic environment by decreasing the lung mRNA levels of transforming growth factor-beta1, connective growth factor and plasminogen activator inhibitor-1 mRNA, but had minimal effects on lung inflammation as assessed by bronchoalveolar lavage cytology analysis. Interestingly, the 5-HT2B receptor was strongly expressed by fibroblasts in the fibroblastic foci in human idiopathic pulmonary fibrosis samples. In conclusion, the present study showed involvement of serotonin in the pathophysiology of bleomycin-induced lung fibrosis in mice and identified it as a potential therapeutic target in lung fibrotic disorders.

Pulmonary sarcoidosis

Sarcoidosis is a multisystemic disease of unknown aetiology characterized by the formation of immune granulomas in involved organs. It is a worldwide disease that mainly affects 25-40 years old people with a lifetime incidence rate of 0.85-2.4%. Multiple clinical phenotypes are observed according to presentation, involved organs, disease duration and severity. Sarcoidosis primarily affects the lungs and the lymphatic system. The prevailing pathogenic hypothesis is that various antigens could promote sarcoidosis in genetically susceptible hosts, both these factors modulating the incidence and the clinical phenotype of sarcoidosis. So far, environmental agents have been suspected, including possible mycobacteria and propionibacteria. Interferon-gamma, tumour necrosis factor (TNF)-alpha, interleukin (IL)-12 and IL-18 play a critical role in driving the Th1 commitment in the course of granulomatous process. Evolution of sarcoidosis is often marked by spontaneous resolution within 12-36 months, but can be severe because of chronic cases with pulmonary fibrosis or involving other organs, including heart, central nervous system and eyes. Mortality, ranging between 0.5 and 5%, is most often related to pulmonary fibrosis. Corticosteroids can reverse the granulomatous process, but are only suspensive, and their long-term benefit remains under question. Corticosteroids are recommended when sarcoidosis shows unfavourable clinical tolerance and evolution. Alternative and corticosteroid-sparing therapies are of increased interest in difficult cases, while targeted new drugs such as anti-TNF-alpha are still under investigation.

An outbreak of Campylobacter jejuni enteritis in a school of Madrid, Spain

An outbreak of gastroenteritis caused by Campylobacter infection was identified in May 2003 in a school in Madrid, Spain. Eighty one cases were identified in a total of 253 people studied. A retrospective cohort study showed that a custard made with ultra high temperature (UHT) milk was associated with illness (RR: 3.15; 95% CI: 1.25-7.93). The custard was probably contaminated with Campylobacter jejuni from a raw chicken prepared a day previously in the same kitchen. Our recommendations were to periodically remind the school s authorities how to act if an outbreak should be suspected, to include the monitoring of a food handler s working day in each environmental investigation in order to detect any risk behaviour; to implement microbiological analysis from the surfaces and utensils of the collective kitchens and improve the sanitary education of food handlers.

An outbreak of Campylobacter jejuni enteritis in a school of Madrid, Spain

An outbreak of gastroenteritis caused by Campylobacter infection was identified in May 2003 in a school in Madrid, Spain. Eighty one cases were identified in a total of 253 people studied. A retrospective cohort study showed that a custard made with ultra high temperature (UHT) milk was associated with illness (RR: 3.15; 95% CI: 1.25-7.93). The custard was probably contaminated with Campylobacter jejuni from a raw chicken prepared a day previously in the same kitchen. Our recommendations were to periodically remind the school’s authorities how to act if an outbreak should be suspected, to include the monitoring of a food handler’s working day in each environmental investigation in order to detect any risk behaviour; to implement microbiological analysis from the surfaces and utensils of the collective kitchens and improve the sanitary education of food handlers.

Expression of apoptosis-regulatory proteins in lesions of pulmonary Langerhans cell histiocytosis

AIMS

Pulmonary Langerhans cell histiocytosis (PLCH) is characterized by the presence of lesions containing numerous activated Langerhans cells (LCs). An uncontrolled immune response sustained by activated LCs seems to be involved in the pathogenesis of the disease. The aim of this study was to establish whether disruption of LC apoptosis related to the expression of the Bcl-2 family proteins is implicated in the maintenance of PLCH lesions.

METHODS

Six patients with PLCH were evaluated by morphological and immunohistochemical techniques to explore the incidence of apoptosis in pathological LCs and to characterize the expression of Bcl-2-related proteins by these cells.

RESULTS

Very few LCs present in PLCH lesions exhibited nuclear apoptotic changes or expressed cleaved caspase-3, whereas they all strongly expressed the anti-apoptotic molecule Bcl-x(L). Interestingly, pulmonary LCs present in intervening lung tissue not involved by the pathological process and known to be immature dendritic cells did not express Bcl-2 family proteins.

CONCLUSIONS

These findings suggest that activated LCs present within PLCH lesions are poorly susceptible to apoptosis and, thus, are able to sustain the pathological process by causing continuous local stimulation of T cells. Functional studies are needed, however, to demonstrate that they are actually resistant to programmed cell death.

Upregulation of bronchioloalveolar carcinoma-derived C-X-C chemokines by tumor infiltrating inflammatory cells

OBJECTIVE AND DESIGN

The presence of increased numbers of tumor-infiltrating neutrophils is associated with poorer outcome in patients with adenocarcinoma of the bronchioloalveolar (BAC) subtype. We evaluated the role of inflammatory environment on C-X-C chemokine tumor production.

MATERIALS

Bronchoalveolar lavage from 31 consecutive patients with adenocarcinoma of the BAC subtype as well as tumor and normal pulmonary tissue samples. A549 BAC cell line. Peripheral blood mononuclear cells (PBMC), polymorphonuclear neutrophils (PMN) and alveolar macrophages (AM).

METHODS

Elisa measurements and immunohistochemical studies of ENA-78, IL-8, IL-1beta and TNF-alpha. RNA isolation, reverse transcription, and PCR amplification of ENA-78 and IL-8.

RESULTS

C-X-C peptides were expressed by tumor cells of all the tumor specimens tested. ENA-78 and IL-8 were also expressed by AM. To better understand the regulation of the C-X-C production, BAC cell line was cultured alone or with inflammatory cells. PBMC upregulated both tumor ENA-78 and IL-8 mRNA expression and protein release whereas AM only upregulated ENA-78 mRNA expression and protein release; PMN had no effect. Anti-human IL-1beta antibodies (ab) inhibited the A549 ENA-78 and IL-8 production stimulated by PBMC-CM. Anti-human TNF-alpha ab inhibited A549 ENA-78 production stimulated by AM-CM. IL-1beta and TNF-alpha were expressed in vivo by inflammatory cells, although TNF-alpha was also expressed by tumor cells.

CONCLUSIONS

This work emphasizes the role of the host inflammatory response in promoting tumor growth in vivo.

Cryptosporidiosis outbreak in British tourists who stayed at a hotel in Majorca, Spain

On 22 July 2003, the Scottish Centre for Infection and Environmental Health

Cytokine profiles in idiopathic pulmonary fibrosis suggest an important role for TGF-beta and IL-10

Modulation of cytokine expression represents a potentially useful approach for the treatment of idiopathic pulmonary fibrosis (IPF). To identify potential targets for such intervention, semi-quantitative reverse transcriptase-polymerase chain reaction was used to compare the expression of messenger ribonucleic acids (mRNAs) coding for 17 cytokines in lung tissue obtained from patients with IPF at the time of diagnosis and control subjects. Some cytokines were also studied at the protein level by immunohistochemical techniques. mRNAs coding for all of the cytokines evaluated were detected in both control and fibrotic lung samples. Only transforming growth factor (TGF)-beta and interleukin (IL)-10 mRNAs were quantitatively increased in lung biopsies from patients with IPF compared with those of controls, results confirmed at the protein level by immunohistochemistry. Although mRNAs for platelet-derived growth factor (PDGF)-BB and keratinocyte growth factor (KGF) were expressed in similar amounts in lungs from patients with IPF and controls, localised accumulation of both factors was also observed in IPF. Hyperplastic alveolar epithelial cells were a prominent source of cytokines, where IL-10, PDGF-BB and KGF were present in increased amounts, although increased accumulation in fibroblasts, smooth-muscle cells and matrix components was also observed (PDGF-BB, TGF-beta). These results offer new insights into the cytokines produced in the lung in idiopathic pulmonary fibrosis and suggest that modulation of the production of transforming growth factor-beta and interleukin-10 may represent a potentially useful therapeutic strategy for this disabling disease.

[Adult pulmonary Langerhans' cell histiocytosis]

INTRODUCTION

Adult pulmonary Langerhans'cell histiocytosis, also referred to as histiocytosis X, is a disorder of unknown etiology which affects preferentially young smokers. The disease is characterized by granulomatous lesions which progressively invade and destroy distal airways, leading to the formation of characteristic cicatricial kystic lesions. Florid granulomas contain numerous Langerhans'cells, antigen-presenting cells of the dendritic cell lineage, associated with T lymphocytes and eosinophils. The diagnosis rests on the combination of clinical and radiologic data, and particularly on high-resolution CT scan findings showing a typical association of nodular and cystic changes, predominantly in the upper and middle lobes. Further evaluation with surgical lung biopsy is indicated in less typical situations.

CURRENT KNOWLEDGE AND KEY POINTS

The pathogenesis of Langerhans'cell histiocytosis is not fully understood, but several arguments suggest that the disease results from an abnormal immune reaction initiated by Langerhans'cells and directed against the bronchial epithelium. Other arguments suggest the presence of genetic abnormalities susceptible, for example, to increase the sensitivity of these cells to cytokines (GM-CSF, or others) known to influence their survival and maturation.

FUTURE PROSPECTS AND PROJECTS

These recent advances in the pathogenesis of Langerhans'cell histiocytosis could promote the development of new therapeutic strategies designed to regulate the number and activated state of Langerhans'cells in specific lesions.

Bronchopulmonary disposition of the ketolide telithromycin (HMR 3647)

Telithromycin (HMR 3647) is the first member of a new family of antimicrobials, the ketolides, developed specifically for the treatment of community-acquired respiratory tract infections. Telithromycin has proven in vitro activity against both common and atypical respiratory tract pathogens. The penetration of telithromycin into bronchopulmonary tissues and subsequent elimination from these sites were evaluated in four groups (groups A, B, C, and D) of six healthy male subjects who received telithromycin at 800 mg once daily for 5 days. Subjects in groups A, B, C, and D underwent fiberoptic bronchoscopy and bronchoalveolar lavage 2, 8, 24, and 48 h after receipt of the last dose, respectively. The concentration of telithromycin in the alveolar macrophages, epithelial lining fluid (ELF), and plasma was determined by the agar diffusion method with Bacillus subtilis ATCC 6633 as the test organism. The concentration of telithromycin in alveolar macrophages markedly exceeded that in plasma, reaching up to 146 times the concentration in plasma 8 h after dosing (median concentration, 81 mg/liter). Telithromycin was retained in alveolar macrophages 24 h after dosing (median concentration, 23 mg/liter), and it was still quantifiable 48 h after dosing (median concentration, 2.15 mg/liter). Telithromycin median concentrations in ELF also markedly exceeded concentrations in plasma (median concentration in ELF, 3.7 mg/liter 8 h after dosing). Telithromycin achieves high and sustained concentrations in ELF and in alveolar macrophages, while it maintains adequate levels in plasma, providing an ideal pharmacokinetic profile for effective treatment of community-acquired respiratory tract infections caused by either common or atypical, including intracellular, respiratory tract pathogens.

[Pathogeny-etiology of sarcoidosis]

It is now well established that sarcoidosis is a granulomatous disorder resulting from an uncontrolled cell-mediated immune reaction in response to unknown antigens. This reaction is characterized by the presence of typical granulomas at the sites of the disease, made of activated macrophages (epithelioid cells) and T lymphocytes. The interactions between both cell types lead to the production of numerous inflammatory mediators which are essential for the development of granulomas. Recently, sarcoid granulomas have been shown to express a Th1 pattern of cytokines. The modulation of the expression of some of them could be useful for the development of new therapies. The etiology of sarcoidosis remains unknown, but recent advances concerning this disorder suggest that it results from various causes involving a particular genetic background and exposure to specific environmental factors. Recent data have emphasized in some patients the expression of particular HLA haplotypes, the polymorphism of various genes, and the presence of oligoclonal T lymphocytes. The characterization of the antigenic specificity of these T cells could be helpful in identifying agents responsible for the disease. The role of mycobacterial agents is still controversial.

Is high-resolution computed tomography a reliable tool to predict the histopathological activity of pulmonary Langerhans cell histiocytosis?

High-resolution computed tomography (HRCT) has proved to be very useful in the diagnosis and follow-up of pulmonary Langerhans cell histiocytosis (PLCH), but the precise relationships between nodules and thin-wall cysts observed by HRCT, and granulomatous or cystic lesions present in lung tissue, remain to be established. The aim of this study was to compare quantitative data obtained by HRCT and those obtained by histopathological examination of corresponding lung tissue specimens in patients with biopsy-proven PLCH. The results demonstrated that the extent of nodular abnormalities was strongly correlated with the density of florid granulomatous lesions in lung tissue. A strong correlation was also found between the extent of cystic abnormalities and the density of cavitary lesions, but the latter included both still inflammatory cavitary granulomas and cicatricial fibrous cysts. Interestingly, small isolated florid granulomas were found in lung tissue from most patients with a predominant cystic CT scan pattern. Taken together, these results demonstrate that HRCT has to be considered with caution to evaluate the histopathological activity of PLCH. Patients presenting with predominant HRCT cystic abnormalities should benefit from a long-term follow-up. Because these patients are susceptible to developing severe respiratory insufficiency, they should also be considered for treatment as soon as an effective therapy for LCH is available.

VACTERL with hydrocephalus and isolated tracheo-oesophageal fistula in a first cousin

A male infant is described of VACTERL with hydrocephalus where a female first cousin of this child had isolated oesophageal atresia with tracheo-oesophageal fistula. Possibly modes of inheritance are discussed.

[Diesel particles and allergy: cellular mechanisms]

Urbain air pollutants, particularly diesel exhaust particles are now known to contribute to the increased prevalence of asthma and allergic rhinitis. Diesel exhaust particles act as adjuvants in the immune response and may lead to the enhancement of allergic inflammation. This was first suggested by epidemiological studies and now largely confirmed by numerous experimental studies in animals and humans. We review the different mechanisms involved, including effects on cytokine and chemokine production, as well as activation of different immune cells. We also discuss the metabolic and cellular activation pathways used by polycyclic aromatic hydrocarbons, allergens and their interaction with diesel particles which act in synergy in this immune response toward IgE production and induction of allergic inflammation.

Evidence that Langerhans cells in adult pulmonary Langerhans cell histiocytosis are mature dendritic cells: importance of the cytokine microenvironment

Because Langerhans cells (LC) in peripheral tissues are generally "immature" cells with poor lymphostimulatory activity, the contribution of immune responses initiated by LC to the pathogenesis of pulmonary LC histiocytosis (LCH) has been uncertain. In this study we demonstrate that LC accumulating in LCH granulomas are phenotypically similar to mature lymphostimulatory dendritic cells present in lymphoid organs. LC in LCH granulomas intensely expressed B7-1 and B7-2 molecules, whereas normal pulmonary LC and LC accumulating in other pathologic lung disorders did not express these costimulatory molecules. The presence of B7+ LC in LCH granulomas was associated with the expression in these lesions, but not at other sites in the lung, of a unique profile of cytokines (presence of GM-CSF, TNF-alpha, and IL-1beta and the absence of IL-10) that is known to promote the in vitro differentiation of LC into cells expressing a lymphostimulatory phenotype. Finally, LCH granulomas were the only site where CD154-positive T cells could be identified in close contact with LC intensely expressing CD40 Ags. Taken together, these results strongly support the idea that an abnormal immune response initiated by LC may participate in the pathogenesis of pulmonary LCH, and suggest that therapeutic strategies aimed at modifying the lymphostimulatory phenotype of LC may be useful in the treatment of this disorder.

In situ expression of B7 and CD40 costimulatory molecules by normal human lung macrophages and epithelioid cells in tuberculoid granulomas

Normal alveolar macrophages (AM) are not efficient in inducing the proliferation of resting T lymphocytes, and, rather, tend to inhibit pulmonary immune responses. In contrast, epithelioid cells (EC), activated macrophages that play an essential role in the course of granulomatous responses, appear to stimulate T cell proliferation efficiently. The inability of macrophages to deliver potent costimulatory signals through the B7/CD28 and CD40/CD40L pathways could explain their weak accessory cell activity. Using MoAbs and immunohistochemical techniques, however, we found that essentially all AM in normal human lung tissue expressed B7-1, B7-2 and CD40 molecules, and most of these cells were strongly positive. Pulmonary macrophages in other compartments also expressed these costimulatory molecules; no differences in expression were observed comparing macrophages from smokers and non-smokers. Most AM recovered by bronchoalveolar lavage from normal lung segments also strongly expressed B7-1, B7-2 and CD40 molecules. In comparison, resting blood monocytes were B7-1- and only moderately positive for B7-2. Activation of monocytes with lipopolysaccharide (LPS) induced expression of these costimulatory molecules to levels similar to that of AM from the control subjects. EC in granulomatous lesions also expressed easily detectable levels of B7-1, B7-2 and CD40. T lymphocytes within and surrounding the granulomas expressed CD28, the counter-receptor for B7, and many of these T cells also expressed B7-1 and B7-2. These findings suggest that both AM and EC can deliver costimulatory signals through B7-1, B7-2 and CD40 molecules, and indicate that the impairment in accessory cell activity observed for normal AM cannot be attributed to the absence of expression of these costimulatory molecules.