Brucellosis 2003 proceedings - PHIDIAS

Poster Session
incubation. All the bottles detected positive by the instrument were subcultured; if not,
blind subcultures were performed at days 11, 16 and 21. By using a 11 days
incubation protocol and considering all bottles from each patient the Vital system
detected 24 positive cultures (77%) and the other 7 were revealed by blind
subcultures while the instrument showed a negative result (missed positive cultures
23%). Earlier detections were seen in 3 days and the latest ones at 11 days. The
median time-to-detection of B. melitensis was 6.6 days and the majority of isolates
(18 isolates, 79.2%) were detected within 7 days of incubation. Cumulative
percentage rates were 4.2%, 12.5%, 29.2%, 58.3%, 79.2%, 87.5%, 96%, 100% for
days 3,4,5,6,7,8,9 and 11, respectively. In our own experience the Vital system is
useful for isolating B. melitensis in blood cultures and a monitoring period of 11 days
can be used for practical reasons. In every case prolonged incubation and periodic
blindly subculturing of negative bottles is required to maximize the recovery of B.
melitensis.
37- EVALUATION OF AN AUTOMATED COMPLEMENT FIXATION TEST
SYSTEM FOR THE DIAGNOSIS OF ACTIVE BRUCELLOSIS.
M. Tognini 1 , P. Ardenghi 1 , E. Clavijo 2 , A. Orduna 3 , S. Jimenez 4 and R. Diaz 5 . (1) DIESSE
Diagnostica Senese SpA, Monteriggioni, Italy. (2) Hospital Virgen de la Victoria, Málaga, Spain. (3)
Departamento de Microbiología, Facultad de Medicina, Valladolid, Spain. (4) Consejería de Salud, La
Rioja, Spain. (5) Departamento de Microbiologia, Universidad de Navarra, Pamplona, Spain.
The CFT is reliable only when carefully standardized throughout. All reagents
involved must be used at optimal reactivity. Therefore it is imperative that all reagents
be carefully prepared and standardized to insure a completely balanced system.
These standardizations, which involve titrations of sheep red blood cells, haemolysin,
complement, and antigens before the test can be properly performed, render the
complement fixation test rather difficult and time consuming. Aim of this work is the
evaluation of the Seramat System for the performance of the CFT for the serological
diagnosis of brucellosis. The Seramat system is composed of the Seramat
instrument, that automatically processes the samples and of diagnostic kits:
haemolytic system set and antigens. The haemolytic system set kit contains pretitrated
and ready-to-use complement and haemolysin and stabilized (6-months shelf
life) sheep red cells. The haemolysin, being monoclonal, assures a higher sensibility
and a minor loss of activity and stability with time compared to the polyclonal ones.
Up to 40 samples/hour can be processed as the reaction takes place at 37°C. The
final results re calculated through the use of a dedicated software. The antigens used
for this work are B. abortus S 19 and B. melitensis cytosolic soluble extract. Sera
were from patients with current and past infection.
38- A COMPARISON OF ANTI-LPS IgG AS MEASURED BY THE 2ME TEST OR
BY ELISA IN HUMAN BRUCELLOSIS.
J.C. Wallach 1,2 , C. A Fossati 2 , M.V. Delpino 2 and P.C. Baldi 2 . (1) Servicio de Brucelosis, Hospital F.J.
Muñiz, Buenos Aires, Argentina. (2) IDEHU, Facultad de Farmacia y Bioquímica, Universidad de
Buenos Aires, Buenos Aires, Argentina.
Among traditional serological tests for human brucellosis, the value of tube
agglutination in the presence of 2-mercaptoethanol (2ME) has remained
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