Pathogenicity of Cronobacter sakazakii isolated from powdered infant formula retailed in Lagos  metropolis, Nigeria

Olubukola Blessing  Oyetibo; Olufunke Bolatito  Shittu; Adebukunola Mobolaji  Omemu

Olubukola Blessing Oyetibo Department of Microbiology, College of Bioscience, Federal University of Agriculture, Abeokuta, Ogun State, 110212 Nigeria
Olufunke Bolatito Shittu Department of Microbiology, College of Bioscience, Federal University of Agriculture, Abeokuta, Ogun State, 110212 Nigeria
Adebukunola Mobolaji Omemu Department of Hospitality and Tourism, College of Food Science and Human Ecology, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria

Keywords: Histopathology, Necrotizing enterocolitis, Heamorrhagic lesion, Neuronal hyperplasia, Vascular thrombosis.

Abstract

Cronobacter sakazakii has been implicated as the causative agent for disease such as sepsis, meningitis and necrotizing

enterocolitis in neonates. One of the routes of entry of the C. sakazakii is through the consumption of contaminated

powdered infant formula. Although powdered infant formula was assumed to be sterile, research has proven otherwise.

The pathogenesis of C. sakazakii is an area of research that has been under explored. No data about the ability of C.

sakazakii to invade the intestinal tissue in Nigeria is available. In this study, two weeks old rats were housed in five per

cage. For each molecularly identified C. sakazakii strain isolated from powdered infant formula retailed in Lagos

metropolis, and serial dilutions (100, 10-1 , 10-2 , and 10-3 ) suspension was prepared in saline. Four groups of rats were

inoculated orally and intraperitoneally with 0.1 mL of either 100, 10-1 , 10-2 , or 10-3 dilution of bacterial. One group of the

rats was injected with normal saline and one group was not injected at all. The rats were observed for clinical signs and

mortality. Then, brain, caecum and liver were aseptically examined for hispathological changes. Sixty-five per cent of the

rats died before day seven; while the remaining 35% were euthanized and the caecum, brain, and liver were used for

histopathological analysis. Bacterial pathogenicity of mice was established with histopathological effects, varying from

moderate stunting of intestinal villi to various degrees of inflammation of the hepatic tissues and dilated vessel along with neutrophil vascularization of cranial tissue. This study indicates that C. sakazakii is a pathogenic organism of mice and can cause huge mortality within seven days of post infection. The infection also induces heamorrhagic lesion, vascular thrombosis and neuronal hyperplasia in cranial tissue of neonate mice, which indicate that the organism upon

gaining entry into the intestine of the mice find its way to the blood, liver, kidney and eventually to the brain.