Flotation—A New Method to Circumvent PCR Inhibitors in the Diagnosis of Lawsonia intracellularis

Table 2

The results from PCR analyses of 24 selected samples prepared by an optimized small-scale flotation setup. Aliquots of the samples had previously been judged as strongly positive^a, weakly positive^b, partly inhibited^c (inh), or inhibited^d by boiling lysate combined with nested PCR.

Samples, previous results
Results, flotation	Strongly positive, n=6	Weakly positive, not inh, n=6	Weakly positive, partly inh, n=6	Inhibited, n=6
Positive	4	1	4	—
Negative	2	5	2	5
Inhibited	—	—	—	1

^aThe signal from the sample amplicon was equal to the positive control and the internal control was outnumbered.
^bThe signal from the sample amplicon was weaker than the signal from the internal control.
^cThe signal from the sample amplicon was equal to the signal from the sample^b but the internal control was not visualised.
^dNo signal was visualised.