[Faecal occult blood testing: comparison of a latex agglutination test (Hemolex) and an immunoturbidimetric test (QuikRead FOB)].
Occult blood detection is the most prescribed faecal examination.


OBJECTIVE
To compare results obtained with the latex agglutination test Hémolex LA (Orion diagnostica, Finlande) with those given by an immuno-turbidimetric test which allows an automatic reading (QuikRead FOB, Orion diagnostica, Finlande).


METHODS
this prospective study was carried out in 140 patients. The reference method was the latex agglutination test, Hemolex LA performed on stool extract obtained through weighting samples. On the base of the results, samples were separated into 2 groups: positive (n = 45) and negative (n = 95). As the QuikRead FOB test indicated a stool extract obtained through a sampling set, such an extraction was performed before Hemolex LA et QuikRead FOB testing.


RESULTS
all the 95 samples from the negative group gave similar results with the 3 methods. In contrast, 12/45 of the positive samples gave conflicting results, 11 results were negative with the 2 tests performed on stool extract obtained via sampling set, 1 result was negative with the QuikRead FOB method only.


CONCLUSIONS
analytical performance were similar with the 2 methods and discrepancies observed wi-thin the positive group were mainly related to the extraction method.
Bardot
L
L
Laboratoire de coprologie fonctionnelle, GH Pitié-Salpêtrière, Paris.
Gobert
J-G
JG
Kapel
N
N
D006801:Humans; D007159:Immunologic Tests; D007841:Latex Fixation Tests; D009780:Occult Blood; D011446:Prospective Studies