A case of hemolytic uremic syndrome documented co-infection of vertoxin producing Escherichia coli O157 and other pathogens

Abstract

We reported a case of a 3-year-old girl with hemolytic uremic syndrome (HUS), which showed hemolytic anemia (Hemoglobin 8.2 g/dl, lactate dehydrogenase 1277 IU/l and total bilirubin 0.6 mg/dl), small purpura on the skin (platelet 7.3 x 10(4)/microliter) and slightly decreased output of urine (creatinine 0.4 mg/dl and blood urea nitrogen 27.2 mg/dl). Verotoxin producing Escherichia coli (E. coli) O157 was not isolated, but Salmonella agona and E. coli O125, which is one of the enteropathogenic E. coli, were detected from her stool culture. However, the IgM antibody against verotoxin producing E. coli (VTEC) O157 lipopolysaccharide was detected in both serum of the acute and convalescent phase by immunoblot assay. In addition verotoxin DNA was demonstrated in the stool by PCR method. Therefore, we think this HUS might be due to VTEC O157, which must have been co-infected with Salmonella agona and E. coli O125. There have been four cases including the present case of co-infection with VTEC O157 so far, and the other three cases were of the Salmonella species. Although the reason of co-infection was unknown, we may infer that food might be contaminated with some pathogens including Salmonella species or that these patients might be already infected with Salmonella species prior to VTEC infection. Even when some other pathogens were detected by a stool culture from a patient with HUS, we should pay attention to demonstrate associated of VTEC and HUS by the specific antibodies and PCR for verotoxin DNA.