Apport de la biologie moléculaire au diagnostic de la tuberculose

Reducing delays in diagnosing tuberculosis should contribute to lower the lethality and to reduce the transmission. Microscopy examination is an easy to perform and rapid technique, but lacks sensitivity and specificity. Culture and biochemical identification are sensitive and specific, but require two to eight weeks DNA probes performed on solid or liquid media are very efficient for M. tuberculosis complex strains identification. Nucleic acid amplification techniques are available to directly detect the M. tuberculosis complex in clinical samples. Performances are variable. Very good results are obtained with experienced teams who scrupulously follow the specified guidelines.     

Leucémie/lymphome T de l'adulte HTLV-1+

Adult T-cell leukemia/lymphoma (ATLL) is a lymphoproliferative disorder of mature T cells caused by human T-cell lymphotropic virus (HTLV-1). The clinical features of the disease can vary greatly. The most common acute subtype is characterised by a combination of generalized lymphadenopathy, hepatosplenomegaly, skin rash, hypercalcemia and circulating neoplastic cells. The diagnosis is suggested by the morphological, immunophenotypical and genetic characteristics of neoplastic cells, histopathological and immunohistochemical features of involved tissues and serological status of patients (HTLV-1 healthy carriers). To confirm the diagnosis it is necessary to show the clonal integration of HTLV-1 in neoplastic cells. Whatever the clinical subtype the prognosis is poor because of cell resistance to conventional intensive chemotherapy.     

Pathologies attribuables à la consommation de coquillages

From a literature survey, a long list of germs and pollutants found in shellfish has been drawn up, which are potential pathogens when eaten. These consist of microbes, which, carried by the effluent from human or animal communities, reach shoreline ponds and oyster production sites. Transmission from faecal material to the eaten seafood is the origin of a variety of clinical conditions: septicaemia, typhoid, viral hepatitis A, neurological syndromes, and gastro-enteritis induced by bacteria, parasites or viruses.Other illnesses are associated with specific agents coming from the water environment: vibrios and toxic seaweeds, whose growth has been affected by nutrients in the untreated, surrounding waters, and depends on climatic and ecological conditions. The treatment of waste water from communities, and the protection of production sites are the sole means of illness prevention, since the case of shellfish, eaten alive and raw, and having been taken directly from the natural production environment, is a paradox in our ⪡hyper-secure⪢ food system.All food intake in the festive season has risks: for these to be acceptable, producers and control mechanisms must work together to reduce them.     

Nouvelles approches dans le traitement des leucémies aiguës de l'enfant

The cure rate of children with acute lymphoblastic leukemia approaches 80 %. Numerous prognostic factors have been identified, based on clinical, biological and therapeutic data. The treatment can be more intensive for patients with a high risk of relapse. On the other hand, a less aggressive therapy may be administered to patients with good probability of long term survival. Prognostic factors of childhood ALL include : age, white blood cell count, cytogenetics, early response to treatment. The detection of minimal residual disease with new molecular or immunological techniques is useful to adapt the intensity of the treatment. Treatment consists of multiagent chemotherapy, with remission induction, consolidation, prevention of central nervous system relapses. For the majority of children with ALL, this treatment is based on intensive systemic therapy and methotrexate administered intrathecally.Delayed intensification has contributed to improve the outcome of childhood ALL. Continuation therapy is required in ALL, with daily administration of 6-mercaptopurine and weekly administration of methotrexate. With more and more patients who become long term survivors of childhood ALL, it is important to evaluate and to prevent the late sequelae.The outcome of patients with acute myeloid leukemia is not as successful as for patients with ALL. Treatment consists of several courses of an association of anthracyclines and aracytine. Genoidentical bone marrow transplantation in first complete remission is indicated for the majority of the patients ; ATRA has substantially improved the prognosis of patients with acute promyelocytic leukemia.The studies of gene expression profile at diagnosis of acute leukemia could improve the characterization of prognostic factors and could help to find new therapeutic targets.