IREB2 and cholesteryl ester measurement: In contrast, the following virulence factors: toxin (hlyF and senB), invasion (AslA), iron uptake (fyuA, iroN, irp2, iucC, iutA, and sitA), and protectin (capU, cia, cma, colE7, cvaC, mchBCF, and mcmA) were frequently present (<43%) in CE isolates and absent from non-CE.