[Use of the Bactec TB 460 method for the bacteriological diagnosis of tuberculosis. Results of a multicenter study]. / Utilisation de la méthode Bactec TB460 pour le diagnostic bactériologique de la tuberculose. Résultats d'une étude multicentrique.

Isolation of Mycobacteria on Loewenstein-Jensen medium lasts many weeks. The use of Radiometric method (Bactec TB 460) reduces the delays. Results of 79,064 cultures are reported from a multicentric study associating 16 laboratories. The average was 4.8% of positivity and 2.51% of contamination. The comparison of the results with conventional method previously obtained shows that radiometric method is more sensitive and contaminations are less numerous. Concerning hemocultures the Bactec method is very usefull. Among 11,277 tests performed 907 were positive (8.04%). Mycobacterium avium was identified in 89% of the cases. Identification test utilizes Biochemical and NAP tests, but also more and more Nucleic probes. The antibiotic sensitivity is performed in five days. The mean delay of analysis is about 25 days, lessening by half the conventional method delays. Nevertheless, Bactec method has the following inconveniences: syringe inoculation, use of radiolabelled products, expensive cost.

[Critical study of techniques for the detection of "light" rheumatoid factors (author's transl)]. / Facteurs rhumatoïdes "légers". Etude critique des techniques de détection.

In a number of cases of true rheumatoid arthritis, it is not possible to demonstrate the presence of 19 S "heavy" rheumatoid factors by the Waaler-Rose and globulin latex techniques. However, in some of them, 7 S rheumatoid factors are suspected. Three techniques for the detection of these "light" rheumatoid factors are described and critically evaluated. The authors report their own experience of the immuno-absorption and indirect immunofluorescence technique performed on 156 sera from RA patients. Immuno-absorption is not felt to be a reliable technique on several grounds. Indirect immunofluorescence is of value only in the diagnosis of seronegative rheumatoid arthritis where it provides information in addition to that offered by classical techniques. It is positive in 53.3% of seronegative rheumatoid arthritis sera.