ABSTRACT
Background: Isolation of Brucellai is the gold standard in the laboratory diagnosis of brucellosis. As Brucellai is intracellular and the number of circulating bacteria is usually low, removal/dilution
of antibacterial substances, concentration of bacteria and optimal culture conditions
may enhance the rate of isolation.
Aims and Objectives: The objective of the following study was to compare the lysis concentration (LC),
clot culture and conventional Castaneda blood culture techniques for the isolation
rate and recovery time in the diagnosis of human brucellosis.
Materials and Methods: Blood cultures by LC, clot culture and conventional method were performed in 169
patients who had antibody titers ≥160 international units by the serum agglutination
test.
Results: Overall blood culture positivity was found to be 24.8%, 43.1% and 34.9% by conventional,
LC and clot culture techniques in that order. The mean recovery time by LC and clot
culture techniques was significantly less than conventional method, resulting in an
overall difference of nearly 6 and 4 days respectively.
Conclusions: For the isolation of Brucellai from blood, LC and clot culture techniques are better than the conventional technique.
Key words:
Blood culture - brucella - clot culture - lysis concentration
