[Tuberculosis: current epidemiological-clinical problems]. / Tuberculose: actuele epidemiologisch-klinische problemen.

Tuberculosis (tb) mortality, morbidity and infection prevalence were very high in Belgium and in the other industrialised countries during the previous century, and the first half of this century. Therefore tb was an "export" pathology, especially towards developing countries. At the end of this century tb-epidemiological indices reached very low levels in the Western world, while tb became endemic in several non-Western countries and so it actually has become an "import" pathology. In the USA, as well as in many European countries, the tb-morbidity incidence started to increase again about ten years ago. The risk groups are, however, not identical in the USA and in Belgium. In the USA, it is particularly the AIDS-epidemic that is the cause of half of the increase in tb-incidence; in addition social outcasts, homeless and IV-drug addicts are important risk groups and due to their poor therapy compliance they are responsible for the many multidrug resistant forms emerging in New York and other large cities. In Belgium elderly males are an important risk group with a tb-incidence of 50 per 10(5) in 1993 (versus an overall incidence of 15 per 10(5)). Besides, in this group the diagnosis is often made late. A second important risk group consists of allochthones, with an incidence of 54 per 10(5), especially non-Western allochthones, with an incidence of 120 per 10(5). Above all others are the asylum seekers with an estimated incidence of 400 per 10(5) (which undoubtedly is an underestimation). In Belgium, the AIDS-epidemic does not represent a major problem so far; only 3.5% of the tb-cases have AIDS or are HIV-positive, and 50% of these are immigrants. Finally, also multidrug resistance is no real problem, since resistance against isoniazide and rifampicin has been found in only 0.5% of the tb-cases. Contact persons of tb-cases, however, still remain a very important risk group with an incidence of more than 200 per 10(5). The danger is especially great for as long as the diagnosis has not been made in the source of infection and no therapeutic measures have been taken. While the overall tb-threat increased in the last decade, the tb-organisations (in Flanders the VRGT, Vereniging voor Respiratoire Gezondheidszorg en Tuberculosebestrijding) have been more or less dismantled, which in consequence may lead to problems in the future!(ABSTRACT TRUNCATED AT 400 WORDS)

[The cobalt lung in diamond cutters: a new disease]. / De kobaltlong bij diamantslijpers: een nieuwe ziekte.

Although for forty years already broncho-pulmonary pathology has been described in workers exposed to hard-metal (i.e. alloys of tungsten carbide and cobalt) and although cobalt is considered the offending agent of this hazard, these abnormalities have almost not been found after exposure to cobalt alone except in animal experiments. Recently we detected clearcut broncho-pulmonary pathology in 48 diamond polishers (i.e. nearly 1% of those exposed) attributable to the ultrafine cobalt dust from the cutting surface of polishing disks, in which it was used as a cementing matrix for microdiamonds without any tungsten carbide. Nineteen of these patients presented with a fibrosing alveolitis documented in 6 by lung biopsy and in 12 by broncho-alveolar lavage, both of which revealed characteristic multinucleated giant cells. Thirteen suffered from asthma of occupational origin, in 9 proven by cobalt-inhalation tests, and in 5 by peak flow measurements at the workplace. Sixteen had mixed bronchial and alveolar pathology or were incompletely documented. A cross-sectional study in about 200 diamond polishers showed a significant correlation between exposure to cobalt and decrease in lung function. The strikingly harmful effects of cobalt can be explained by the chronic exposure to very small particles with markedly increased solubility. The pathogenesis of the broncho-pulmonary pathology may be attributed to the cytotoxic as well as to the sensitising (i.e. allergic and/or idiosyncratic) actions of cobalt.

The inherited association of interstitial lung disease, hypocalciuric hypercalcemia, and defective granulocyte function.

The history and pulmonary histopathology of 3 siblings, presenting with the association of idiopathic interstitial lung disease, hypocalciuric hypercalcemia, and an intrinsic defect in granulocyte function are described. Prospective examination of 40 family members indicated that the 3 abnormalities are inherited according to an autosomal dominant pattern with, however, a variable penetration. Lung biopsies in the index cases revealed an interstitial infiltration of inflammatory cells and aggregates of conchoid bodies surrounded by multinucleated giant cells. Bronchoalveolar lavage was performed in 11 subjects and often showed an elevated cell recovery and abnormal cell distribution indicative of active alveolitis. In several subjects, multinucleated giant cells were found. The diffusing capacity (in percent predicted) showed a significant decrease with age, independent of smoking habits. The hypocalciuric hypercalcemia was unaffected by steroids or parathyroidectomy. It was not associated with abnormal levels of parathyroid hormone, calcitonin, 25-hydroxy-vitamin D3, 1,25-dihydroxy-vitamin D3, or angiotensin-converting enzyme.

Cobalt lung in diamond polishers.

Five diamond polishers with interstitial lung disease attributed to cobalt not alloyed to carbides of hard metals are described. The exposure originated from high-speed grinding tools with a polishing surface of microdiamonds cemented in very fine cobalt. Mineralogic analysis of lung tissue, lavage fluid, filtered air, and exhaust dust in the work environment revealed cobalt as the only toxic agent. Complaints consisted of work-related rhinitis, cough, chest tightness, dyspnea, anorexia, and weight loss, and were intensified in the absence of an adequate exhaust ventilation. Three subjects were in a rather subacute stage, as documented by open lung biopsy in 2 of them, and had a severe restrictive defect and markedly decreased diffusing capacity. Two patients presented a more chronic histologic pattern and had a less decreased diffusing capacity. Open lung biopsies showed in these 4 a fibrosing alveolitis, mainly of the centrilobular zones. In the former 2 patients, subacute lesions consisting of a mural mononuclear cell infiltrate, marked intra-alveolar desquamation, and multinucleated giant cells were found, whereas in the latter 2, centrilobular fibrosis with some microcyst formation was also already seen. Multiple multinucleated giant cells were present in the bronchoalveolar lavage fluid. Interruption of the exposure, with or without corticotherapy, caused a rapid regression of the complaints and a partial improvement of lung function.

Cervical mediastinoscopy and anterior mediastinotomy in patients with lung cancer and radiologically normal mediastinum.

In the period 1975-1980, 1504 patients presented with lung cancer, 291 were presumably operable, and had no radiological evidence of mediastinal lymph node invasion. Two thirds (192 patients) underwent pre-operative surgical mediastinal exploration, and one third (99 patients) were operated right away. Of the 162 cervical mediastinoscopies, 16% had lymph node invasion (19.7% with right-sided, 10.6% with left-sided tumor); 28.9% of the 45 left-anterior mediastinotomies were positive. There was only one positive cervical mediastinoscopy of 46 cases with lower-lobe tumor, and no positive anterior mediastinotomy in 5 cases with left lower-lobe tumor. Mediastinal exploration yields, thus, a relatively higher percentage of positive results if the cervical mediastinoscopy is restricted to tumors affecting the right upper and middle lobes (25%), and if the anterior mediastinotomy is restricted to the left upper lobe (32.5%). A left anterior mediastinotomy should, thus, be recommended instead of cervical mediastinoscopy for tumors of the left upper lobe.

Rifampim-combined chemotherapy in coal worker's pneumoconio-tuberculosis.

Results of a retrospective study of rifampin-combined chemotherapy in 59 coal miners with pneumoconio-tuberculosis are reported. In 43 patients pneumoconiosis had attained the stage of progressive massive fibrosis. The follow-up period ranged from 24 to 78 months, except in 8 patients who died before the twenty-fourth month. Twenty-seven of the 59 patients were treated for the first time, and 32 were in retreatment. In none of them had rifampin been administered before. Although the objective was to administer rifampin in combination with one, 2, or even 3 companion drugs that had not been administered before and that had proved to be active on the patients' bacilli in vitro, this goal was fully reached only in the first treatment group; in 8 of the 32 retreated patients the drugs combined with rifampin were considered ineffective. The speed and rate of bacteriologic conversion were most impressive. Sputum conversion was obtained in 90 per cent of the patients; in the initial treatment group 100 per cent of the patients converted their sputum on culture at 5 months and in the retreatment group the corresponding figure was 84.4 per cent. These bacteriologic results are nearly as favorable as those obtained in cases of advanced pulmonary tuberculosis without pneumoconiosis treated with the same rifampin-containing drug regimens. It was concluded that rifampin-combined chemotherapy largely eliminates the handicap caused by the coexistence of tuberculosis and pneumoconiosis. Side effects due to rifampin were without practical significance. In 3 patients of 57 treated with ethambutol, visual impairment was observed. Mortality was high (27 per cent) but was caused by nontuberculous diseases, especially cardiorespiratory insufficiency. In 10 of the 16 patients who died, death occurred after bacteriologic conversion.