What is the management of Shiga toxin-producing Escherichia coli (E. coli) infection?

From the Guidelines

Management of Shiga toxin-producing Escherichia coli (STEC) infection primarily involves supportive care with close monitoring for complications, and antibiotics are generally not recommended as they may increase the risk of hemolytic uremic syndrome (HUS) by triggering increased toxin release. Treatment focuses on maintaining hydration through oral rehydration solutions or intravenous fluids depending on severity, as stated in the 2017 Infectious Diseases Society of America clinical practice guidelines for the diagnosis and management of infectious diarrhea 1. Electrolyte imbalances should be corrected as needed. Anti-diarrheal medications like loperamide should be avoided as they can slow toxin clearance and potentially worsen outcomes. Patients require careful monitoring of kidney function, blood counts, and neurological status to detect early signs of HUS, which occurs in 5-10% of STEC infections, particularly in children under 5 years, as noted in the guidelines 1. If HUS develops, specialized care may include dialysis, blood transfusions, and intensive supportive measures. Prevention of spread through proper hand hygiene and food safety practices is essential. Healthcare providers should report cases to public health authorities to identify potential outbreaks. Most patients recover within 5-10 days with appropriate supportive care, though those who develop HUS may have longer recovery periods and potential long-term complications.

Some key points to consider in the management of STEC infection include:

• The importance of early identification of STEC infections to reduce the risk of complications and person-to-person transmission, as highlighted in the guidelines 1.
• The need to perform both cultures for STEC O157 and test for Shiga toxin (or the genes that encode this toxin family) to detect all STEC serotypes, as recommended in the guidelines 1.
• The association between STEC carrying Shiga toxin 2 (stx2) genes and increased risk of both bloody diarrhea and HUS, as noted in the guidelines 1.
• The potential for new multiplex nucleic acid amplification tests (MP-NAATs) to detect evidence of multiple pathogens and toxins, and to distinguish between Shiga toxins 1 and 2, as discussed in the guidelines 1.

Overall, the management of STEC infection requires a careful and supportive approach, with a focus on preventing complications and promoting recovery, as emphasized in the guidelines 1.

From the Research

Management of Shiga Toxin E Coli Infection

• The management of Shiga toxin-producing Escherichia coli (STEC) infections is crucial to prevent the development of hemolytic uremic syndrome (HUS) 2.
• Certain management practices optimize the likelihood of good outcomes, such as avoidance of antibiotics during the pre-hemolytic uremic syndrome phase, admission to hospital, and vigorous intravenous volume expansion using isotonic fluids 2.
• The successful management of STEC infections is based on recognition that a patient might have an STEC infection, and appropriate use of the microbiology laboratory 2.

Treatment Options

• There is no specific form of therapy for STEC HUS, but appropriate fluid and electrolyte management, avoiding antidiarrheal drugs, and possibly avoiding antibiotic therapy, are recommended as the best practice 3.
• Antibiotics should not be used to treat STEC infections, as they may increase the risk of developing HUS 4.
• Interventions such as antibiotics, bovine colostrum, Shiga toxin binding agents, and monoclonal antibodies against Shiga toxin have been investigated, but the evidence is uncertain and more studies are needed to assess their efficacy 5.

Long-term Outcomes

• The outcomes of STEC HUS have improved, and the acute mortality rate in children is 1-4% 6.
• About 70% of patients recover completely from the acute episode, and the remainder have varying degrees of sequelae, including proteinuria, hypertension, chronic kidney disease, and end-stage kidney disease 6.
• Length of anuria and prolonged dialysis are the most important risk factors for a poor acute and long-term renal outcome 6.

Differential Diagnosis

• STEC-associated HUS can be considered in differential diagnosis with the onset of inflammatory bowel disease (IBD), as the clinical presentation and symptoms may be similar 3.
• Severe gastrointestinal involvement may result in life-threatening complications, such as toxic megacolon and transmural necrosis of the colon with perforation, similar to IBD 3.