Benign asbestos-related pleuropulmonary diseases

Among the non malignant diseases related to asbestos exposure, pleural plaques are the most frequent. Pleural effusion and diffuse pleural thickening, as well as asbestosis, are uncommon nowadays in asbestos-exposed screened populations. Despite the absence of any useful treatment, accurate diagnoses of these diseases are needed for two reasons: on the one hand in order to save patients from anxiety related to diagnostic and prognostic discrepancies, and on the other hand in order to ensure a proper attribution of the high social and financial compensations which are provided in France for asbestos affected patients. CT scan of the thorax is the most sensitive and specific tool for a precise diagnosis of these lesions, but it often displays minute abnormalities which may give rise to major diagnostic discordances, owing to the absence of any tomodensitometric reference in populations proved to be free from any asbestos exposure. There is a need to seek for a suitable standardization of imaging technique and interpretation, for a consensus in the characterization of CTscan abnormalities that warrant compensation, and for a careful medico-psychologic assistance for patients affected by asbestos-related benign diseases.     

Quels outils doivent être utilisés pour le suivi post-professionnel ? Quel est le rythme de ce suivi ?

As long as the value of screening for cancers related to asbestos is not proven in the population at risk, the medical benefits of follow-up post-professional exposure remain uncertain and the only justification is to answer the questions of anxious retired workers concerning the consequences of their past-exposure and to provide compensation for any abnormalities that are demonstrated. In this country, to answer the questions posed in the title of this contribution in the case of pathologies related to asbestos, it is necessary, after verifying the fact and the level of exposure, to identify the pleural or pulmonary fibrosis and, above all, the pleural plaques, which constitute the essential lesions currently screened for. Thoracic CT scanning without contrast is the examination of choice to achieve this objective. There are, however, two significant problems. On one hand there is a high incidence of pulmonary micronodules, the necessary surveillance of which requires subsequent scans, leading to increased irradiation and anxiety. On the other hand the diagnostic uncertainty concerning discrete lesions is a source of confusion for the persons followed-up. There are, at present, neither scientific criteria to determine the optimum frequency of examination nor any arguments for replacing the pragmatic proposals of the consensus conference of 1999. It is important, therefore, to provide a medical assessment appropriate to the symptoms and anxiety expressed by a person previously exposed to asbestos. Overall it is necessary to question the benefit to the exposed person, in terms of quality of life, of a regular search for lesions that would usually be asymptomatic if not identified. Would it not be more judicious and more equitable to compensate persons whose past-exposure is sufficient to increase significantly their risk of cancer independently of the presence of benign abnormalities.     

Acute respiratory distress revealing acute myeloblastic leukaemia: case report

We report on the case of a patient diagnosed with acute leukaemic transformation of chronic myelomonocytic leukaemia. Its development was characterised by blastic pulmonary localisation and response to corticosteroids. We discuss the etiologies of respiratory distress in acute myeloblastic leukaemia and the corticosteroid sensitivity of this myeloid disease.     

Therapeutic of respiratory manifestations at the early phase of acute myeloid leukaemia

The effective management of the respiratory manifestations at the early phase of acute myeloid hemopathies, especially acute myeloid leukaemia, frequently requires a close collaboration between hematologists, pulmonologists and intensivists. Dominated by infectious etiologies, there are however "specific" disease entities that should not be neglected in the diagnostic and therapeutic approach. These include lung leukostasis, leukemic lung infiltration, the cell lysis pneumopathy and the secondary alveolar proteinosis. These were the subject of a review in the Revue des Maladies Respiratoires published in 2010. We wished to review the management of these clinical situations, the severity of which mean patients frequently require intensive care unit admission. We are only able to make proposals for management here as there is little consensus, except in the metabolic care of tumour lysis syndrome. These data must therefore be reinterpreted regularly as new publications become available.     

Occupational exposures and colorectal cancers: A quantitative overview of epidemiological evidence

A traditional belief widespread across the biomedical community was that dietary habits and genetic predisposition were the basic factors causing colorectal cancer. In more recent times, however, a growing evidence has shown that other determinants can be very important in increasing (or reducing) incidence of this malignancy. The hypothesis that environmental and occupational risk factors are associated with colorectal cancer is gaining ground, and high risks of colorectal cancer have been reported among workers in some industrial branches. The aim of this study was to investigate the epidemiologic relationship between colorectal cancer and occupational exposures to several industrial activities, by means of a scientific literature review and meta-analysis. This work pointed out increased risks of colorectal cancer for labourers occupied in industries with a wide use of chemical compounds, such as leather (RR = 1.70, 95%CI: 1.24-2.34), basic metals (RR = 1.32, 95%CI: 1.07-1.65), plastic and rubber manufacturing (RR = 1.30, 95%CI: 0.98-1.71 and RR = 1.27, 95%CI: 0.92-1.76, respectively), besides workers in the sector of repair and installation of machinery exposed to asbestos (RR = 1.40, 95%CI: 1.07-1.84). Based on our results, the estimated crude excess risk fraction attributable to occupational exposure ranged from about 11% to about 15%. However, homogeneous pattern of association between colorectal cancer and industrial branches did not emerge from this review.     

Occupational exposures and chronic respiratory symptoms. A population-based study

Data from a random sample of 8,515 white adults residing in 6 cities in the eastern and midwestern United States were used to examine the relationships between occupational exposures to dust or to gases and fumes and chronic respiratory symptoms; 31% of the population had a history of occupational dust exposure and 30% reported exposure to gas or fumes. After adjusting for smoking habits, age, gender, and city of residence, subjects with either occupational exposure had significantly elevated prevalences of chronic cough, chronic phlegm, persistent wheeze, and breathlessness. The adjusted relative odds of chronic respiratory symptoms for subjects exposed to dust ranged from 1.32 to 1.60. Subjects with gas or fume exposure had relative odds of symptoms between 1.27 and 1.43 when compared with unexposed subjects. Occupational dust exposure was associated with a higher prevalence of chronic obstructive pulmonary disease as defined by an FEV1/FVC ratio of less than 0.6, when comparing exposed and unexposed participants (OR = 1.53, 95% Cl = 1.17-2.08). Gas or fume exposure was associated with a small, but not significant, increase in COPD prevalence. Significant trends were noted for wheeze and phlegm with increasing duration of dust exposure. Although 36% of exposed subjects reported exposure to both dust and fumes, there was no evidence of a multiplicative interaction between the effects of the individual exposures. Smoking was a significant independent predictor of symptoms, but did not appear to modify the effect of dust or fumes on symptom reporting. These data, obtained in random samples of general populations, demonstrate that chronic respiratory symptoms and disease can be independently associated with occupational exposures.     

A bilateral diaphragmatic paralysis due to Parsonage and Turner syndrome--its evolution over eight years

The diaphragmatic paralysis is a rare disease whose causes and evolving forms are numerous. We report the development to eight years of paralysis diaphragmatic bilateral attributed to a Parsonage-Turner syndrome: the lack of recovery is proved by respiratory functional follow-up. The therapeutic possibilities, limited, are discussed.     

Prévalence et valeur diagnostique des anticorps antinucléaires de spécificité antigénique indéterminée : étude rétrospective à propos d’une série de 90 patients

Purpose

The objective of this study was to determine the clinical relevance and the diagnostic significance of positive antinuclear antibodies (ANA) without identified antigenic target by the usual characterization technique.

Patients and methods

Retrospective study conducted in the Laboratory of Immunology of Habib Bourguiba Hospital (Sfax, Tunisia) during 18 months. The inclusion criteria were the presence of an ANA titer greater or equal to 1/320 with negative characterization result. ANA screening was performed by indirect immunofluorescence (IIF) on Hep2 cells. Each positive serum was tested by IIF on Crithidia luciliae (anti-native DNA) and by immunodot (anti-nucleosome, anti-histone, anti-Sm, anti-RNP, anti-SSA, anti-SSB, anti-Scl 70, anti-PM-Scl, anti-Jo1, anti-PCNA and anti-ribosomal protein). Sera of systemic lupus erythematosus (SLE), myositis, and scleroderma patients were tested for anti-Ku, anti-PL7, anti-PL12 and anti-Ro-52 using dot myositis.

Results

Sera of 90 patients were studied: 18 men and 72 women (average age: 44 years). Drug-induced ANA was found in eight patients. The most frequent clinical symptoms were joint (56.7%), cutaneous (54.4%) and constitutional symptoms (45.6%). The diagnosis of an autoimmune disease was suspected in 49 patients (54.5%) and confirmed in 30 (33.3%) including 20 cases of connective tissue disease: myositis (n = 6), scleroderma (n = 5), Sjögren's syndrome (n = 3), SLE (n = 4), rheumatoid arthritis (n = 6) and antiphospholipid syndrome (n = 4). Other autoimmune diseases were less frequent. The anti-Ku antibody was detected in the majority of patients with connective tissue disease. The diagnosis of non-autoimmune diseases was established in 25.5% of patients. Eighteen patients (20%) had no diagnosis orientation.

Conclusion

Our study demonstrated the diagnostic value of the presence of ANA even in the absence of known antigenic target, confirmed the role of the IIF as “gold standard” test for ANA screening, and suggested the usefulness of the addition of Ku antigen in the immunodot classic profile.     

Intérêt des allergènes recombinants dans le diagnostic de l’allergie alimentaire

To date, neither in vitro nor in vivo tests can establish with reliability the diagnosis of food allergy. The availability of recombinant allergens (RA) has led to improvement in the standardization of allergenic extracts and enrichment of natural extracts, resulting in more sensitive screening tests. These biotechnological advances facilitate the diagnostic approach which now rests on an individual reaction profile (component resolved diagnosis) with well-characterized allergens classified on a molecular basis. Development of diagnostic tests using RA or peptides expressing some distinctive epitopes of interest may improve the prediction of severe and/or persistent food allergies and guide the choice of the therapeutic measures that follow.