ABSTRACT. Vieira T.B., Pereira V.L.A., Franco R.M., do Nascimento E.R., Silva R. de C.F. & Tortelly R. [Pathogenic potential and septic character of the Escherichia coli by identification of virulence factors iss and felA from cellulitis and offal of broiler by Sanitary Inspection.] Potencial patogênico e caráter séptico de Escherichia coli pela identificação dos fatores de virulência iss e felA em celulite e miúdos de frangos sob Inspeção Sanitária. Revista Brasileira de Medicina Veterinária, 36(2):144-152, 2014. Departamento de Medicina Veterinária. Universidade Federal do Mato Grosso, Campus Universitário de Sinop, Avenida Alexandre Ferronato, 1200, Setor Industrial, Sinop, MT 78557367, Brasil. E-mail: firstname.lastname@example.org Brazil is the third largest chicken producer and first in exports of broiler meat. Skin lesions such as avian cellulitis are becoming increasingly frequent in large-scale production due to premises type and management of broilers, leading to total or partial condemnation at slaughter throughout the world. In this study, we used 51 broilers with typical lesions of cellulitis, diagnosed by Sanitary Inspection. Recovery of Escherichia coli strains from cellulitis lesions and offal (liver and heart) from studied broilers established the of septic characteristic of the isolates. These E. coli isolates were tested by Polymerase Chain Reaction (PCR) for the genes of the virulence factors responsible for adhesion (F11 fimbria-felA) and serum resistance (iss). The cellulitis at inspection was characterized as skin ulcer, being eight with skin thickening, color changes tending to reddish-yellow, and irregular skin surface. At cutting, gelatinous fluid and yellowish patches were seen, in some cases, with involvement of the adjacent musculature. E. coli was isolated from 50 broilers, being 19, from cellulitis, 11 from cellulitis and liver, five from cellulitis and heart, 14, from cellulitis, liver and heart, and one only from liver and heart. E. coli isolates were recovered from 96% of cellulitis, 50.98% from liver and 41.17% from the heart samples. There was no significant association between cellulitis lesion size and E. coli rate of recovery from cellulitis and offal (liver and heart) by chi-square test (p> 0.05). Of 190 E. coli isolates from the 51 studied broilers, 59.47% were positive for iss gene and 4.2% for the felA gene. The recovery of E. coli from cellulitis and offal strengthen the idea that the partial removal of cellulitis lesions at slaughter only minimizes the repulsive aspect of the carcass which turns out to be more aesthetic than hygienic, not contributing to poultry products safeness.