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Mycobacterium avium subsp. avium and M. intracellulare are ubiquitous organisms in the environment. The reservoir of M. avium subsp. avium is generally accepted to be environmental, in particular, water and soil are sources of the organism. In contrast to M. avium infection in wild and domestic birds, M. avium infection in mammals occurs only sporadically and is rarely transmissible. Generalised disease is usually uncommon, owing to the non-progressive, chronic character of the infection. However, some cases of disseminated disease have been reported, e.g. in captive non-domestic hoofed animals as well as in immunosuppressed dogs and cats. The majority of M. avium and M. intracellulare infections in livestock are detected at slaughter and the diagnosis is confirmed by bacteriological procedures. Condemnation of affected portions of the carcass can result in significant economic losses, although gross lesions are mostly restricted to lymph nodes close to the alimentary tract. Successful treatment with antibiotics in combination with surgery has been reported in some affected domestic cats, but is not considered to be effective or economical in other species. In the past, differentiation of M. avium bacteria from the closely related M. avium subsp. paratuberculosis was based on the mycobactin dependence and prolonged incubation period of the latter. More recently, amplification of the genomic insertion sequence IS900 has proved to be a powerful tool for identification of M. avium subsp. paratuberculosis. The potential zoonotic importance of M. avium infections has been indicated, but requires clarification.

Un antigene glycolipidique a ete isole, purifie et caracterise a partir de Mycobacterium bovis An5. L'analyse chimique conjuguee a la spectroscopie infrarouge et a la resonance magnetique nucleaire a montre que ce glycolipide etait un diacyl-trehalose (DAT)-le 2,3-di-O-acyl trehalose-semblable a celui de M. tuberculosis. Cet antigene a ete utilise pour la mise au point d'un ELISA pour le serodiagnostic des bovins infectes par M. bovis. La sensibilite et la specificite de l'ELISA ont ete etudiees a l'aide des serums de bovins provenant de troupeaux indemnes de tuberculose et de troupeaux infectes par M. bovis. Aucune correlation n'a ete mise en evidence entre l'ELISA-DAT et l'intradermotuberculination, et entre l'ELISA-DAT et l'interferon gamma. Il semble que les titres d'anticorps ne soient pas lies a l'immunite cellulaire. Bien que l'antigene soit hautement specifique (95,9%), la sensibilite de l'ELISA-DAT, d'apres les essais confirmant bacteriologiquement la tuberculose, est faible (29 a 36,8%). La faible sensibilite de l'ELISA pourrait egalement etre attribuee a une relation reciproque entre la proliferation des cellules B et l'immunite protectrice due aux cellules T.

Un cas de tuberculose pulmonaire est décrit chez le dromadaire à Nouakchott (Mauritanie). Les lésions macroscopiques concernent le parenchyme pulmonaire, la plèvre diaphragmatique, le péricarde et les noeuds lymphatiques : nodules caséo-calcaires, tubercules miliaires et pendeloques hémorragiques. Au plan histologique, les lésions sont de type granulomateux, épithélioïde et à centre nécrotique, mais ne présentent pas de cellules géantes de Langhans. Mycobacterium bovis est isolé des prélèvements.

INTRODUCTION ANAEMtA IS a common cause of morbidity in cancer patients [1]. The lack of the normal feedback mechan i sm that stimulates the erythropoietic response to anaemia is one of the most interesting mechanisms implicated in the genesis of anaemia in these patients. Miller et al. [2] have demonstrated a significantly lower serum erythropoietin level in anaemic cancer patients compared to iron-deficient anaemic patients with equivalent haemoglobin values. This characteristically low erythropoietin response to anaemia in cancer patients reflects the lack of a l i nea r r e l a t i o n s h i p be t w e e n erythropoietin and haemoglobin levels in neoplastic disease. In iron deficiency or haemolytic anaemia, on the other hand, lower haemoglobin levels are directly related to higher erythropoietin levels [2]. The mildly blunted erythropoiesis found in cancer patients worsens with chemotherapy. Although the haematological toxicity of antineoplastic agents is usually more pronounced in white than in red blood cells, the nephrotoxic agent cisplatin exerts an especially toxic effect on erythropoiesis. Cisplatin-associated anaemia is generally normochromic, normocytic, with an inappropriately low reticulocyte count and a low erythropoietin response to anaemia [3,4]. Various trials have shown a greater than 2 g/dl haemoglobin drop in 9 to 40% of patients receiving a standard dose of cisplatin [5]. Although there is currently no sure relationship between cisplatin dosage and anaemia severity, cumulative dose and haemoglobin level seem to be related [6]. The present study, which is ongoing, is being conducted to establish whether or not the use of exogenous erythropoietin (r-HuEPO) in cancer patients can prevent cisplatin-induced ia t rogenic anaemia , and thereby improve this agent ' s therapeutic index.

Les constituants des milieux de Watson-Reid, de Herrold et de Middlebrook 7H10 sont compares a ceux du milieu de Loewenstein-Jensen. De plus l'influence des facteurs speciaux (albumine, dextrose, catalase) sur la croissance en milieu 7H10 est etudiee. La culture de souches de mycobacteries mycobactine-dependantes sur ces milieux est evaluee, en particulier celle des mycobacteries appelees Mycobacterium ⪡wood-pigeon⪢. Trois groupes de mycobacteries ont ete separes suivant leur exigence en facteur de croissance, ce qui a entraine les auteurs a recommander l'utilisation simultanee de milieux contenant de la mycobactine et du milieu de Middlebrook 7H10.