What are the symptoms of E. coli infection?
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Symptoms of E. coli Infection
Common Symptoms: Diarrhea and Abdominal Cramps
Diarrhea is the most frequently reported symptom of E. coli infection, often presenting as either bloody or non-bloody diarrhea. Bloody diarrhea, also known as hemorrhagic colitis, is particularly associated with E. coli O157:H7 infections. Non-bloody diarrhea is also common and can range from mild to severe, with some cases experiencing up to 40 bowel movements per day. Abdominal cramps are another prevalent symptom, often severe and debilitating .
Additional Gastrointestinal Symptoms: Vomiting and Nausea
Vomiting and nausea are also reported, though less frequently than diarrhea and abdominal cramps. Vomiting is more common in children than in adults. In some cases, E. coli infections can cause mucoid diarrhea, which is characterized by the presence of mucus in the stool.
Systemic Symptoms: Fever and Fatigue
Fever is documented in less than half of the cases of E. coli O157:H7 infections. However, it is more commonly observed in children with atypical enteropathogenic E. coli (aEPEC) infections. Fatigue and a general feeling of malaise can accompany these symptoms, particularly in severe cases.
Severe Complications: Hemolytic Uremic Syndrome and Thrombotic Thrombocytopenic Purpura
Severe complications such as hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) can occur, especially in vulnerable populations like the very young and the elderly. HUS is characterized by the destruction of red blood cells, leading to kidney failure, and can be life-threatening. TTP involves blood clot formation in small blood vessels, which can lead to organ damage.
Neurological Symptoms: Cognitive Impairment and Seizures
During the 2011 outbreak of Shiga toxin-producing E. coli O104:H4 in Germany, a significant number of adult patients developed neurological symptoms. These included cognitive impairment, aphasia, and epileptic seizures. Neurological symptoms typically appeared a few days after the onset of diarrhea and were associated with increased levels of blood urea nitrogen and serum creatinine.
Asymptomatic Carriage
Interestingly, a high proportion of E. coli infections can be asymptomatic, meaning individuals carry the bacteria without showing any symptoms. This asymptomatic carriage can still pose a risk of transmission to others.
Conclusion
E. coli infections present a broad spectrum of symptoms, ranging from mild gastrointestinal issues like diarrhea and abdominal cramps to severe complications such as HUS and neurological symptoms. Understanding the variety of symptoms and their severity can aid in early diagnosis and treatment, potentially reducing the risk of severe outcomes.
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