Escherichia coli O104:H4

Pathophysiology

E. coli O104 is a Shiga toxin–producing E. coli (STEC). The toxins cause illness and the associated symptoms by sticking to the intestinal cells and aggravating the cells along the intestinal wall. This, in turn, can cause bloody stools to occur. Another effect from this bacterial infection is hemolytic uremic syndrome (HUS), which is a condition characterized by destruction of red blood cells, that over a long period of time can cause kidney failure.Some common symptoms of HUS are vomiting, bloody diarrhea, and blood in the urine.

Infection

A common mode of E. coli O104:H4 infection involves ingestion of fecally contaminated food; the disease can thus be considered a foodborne illness. Most recently in 2011, an outbreak of the  O104:H4 strain in Germany caused the death of several people, and landed hundreds of citizens in hospital. German authorities traced the infection back to fenugreek sprouts grown from contaminated seeds imported from Egypt, but these results are debated.

Diagnosis

To diagnose infection with STEC, a patient's stool (feces) can be tested in a laboratory for the presence of Shiga toxin. Testing methods used include direct detection of the toxin by immunoassay, or detection of the stx2 gene or other virulence-factor genes by PCR. If infection with STEC is confirmed, the E. coli strain may be serotyped to determine whether O104:H4 is present.

Treatment

E. coli O104:H4 is difficult to treat as it is resistant to many antibiotics, although  it is susceptible to carbapenems.

Prevention

Spread of E. coli is prevented simply by thorough hand-washing with soap, washing and hygienically preparing food, and properly heating/cooking food, so the bacteria are destroyed.