Co-Infection by <em>Escherichia coli</em> O128, <em>Streptococcus equi</em> <em>subsp</em> <em>zooepidemicus</em>, <em>Klebsiella oxytoca</em> and <em>Enterococcus durans</em>, Ended Fatally–A Clinical Case

Escherichia coli, Streptococcus equi subsp zooepidemicus, Klebsiella oxytoca and Enterococcus durans cause a wide range of diseases in both animals and humans. These microorganisms are associated with fatal disease in immunocompromised and comorbid patients. The aim of this study is to present a rare clinical case of an unusual mixed infection of the indicated pathogens, which ended fatally. We found no such clinical case described in a patient with a fatal outcome in our literature review. We present a 65-year-old man admitted at the Clinic of Infectious Diseases, St. George University Hospital, Plovdiv, with severe diarrheal syndrome in a state of toxic-infectious shock. Patient has been ill for 2 days with general weakness, chest and abdominal pain, fever, and about 10 liquid, light brownish stools daily, without mucus and blood. One day before the onset of complaints, he consumed green salad and lamb. He has some accompanying diseases-chronic heart and liver failure with complications. After hospitalization, the patient's condition rapidly worsened, leading to death. Escherichia coli and Streptococcus equi subsp zooepidemicus were isolated from the microbiological examination of cadaver material from the intestinal wall, and from the spleen Klebsiella oxytoca and Enterococcus durans. Histological examination confirmed catarrhal enteritis with characteristic changes–fibrinous plaques, edema in the wall and mucosa and inflammatory infiltrate. To our knowledge, the present clinical case is the first report of a mixed infection by these four pathogens.