What is enterohemorrhagic E. coli?

Escherichia coli (or simply E. coli) is one of the many groups of bacteria that normally live in the intestines of healthy humans and most warm-blooded animals. E. coli bacteria help maintain the balance of normal intestinal bacteria against harmful bacteria.

However, there are hundreds of types or strains of E. coli bacteria. Different strains of E. coli have different characteristics.

One E. coli strain that causes a severe intestinal infection in humans is known as enterohemorrhagic E. coli (EHEC). It’s the most common strain to cause illness in people. It’s different from other E. coli because it produces a potent toxin called Shiga toxin. This toxin damages the lining of the intestinal wall, causing bloody diarrhea.

Enteropathogenic Escherichia coli (EPEC) is a gram-negative bacterial pathogen that adheres to intestinal epithelial cells, causing diarrhea.

Enterotoxigenic Escherichia coli (E. coli), or ETEC, is an important cause of bacterial diarrheal illness. Infection with ETEC is the leading cause of travelers’ diarrhea and a major cause of diarrheal disease in lower-income countries, especially among children.

Enterotoxigenic Escherichia coli (ETEC) LT is a significant marker for gastrointestinal health analysis. ETEC is a leading cause of traveler's diarrhea and is also a common contributor to diarrheal illnesses in developing countries, particularly affecting children. The "LT" in ETEC LT refers to the heat-labile enterotoxin produced by these bacteria. This toxin, similar in structure and function to cholera toxin, disrupts normal intestinal function by increasing the secretion of water and electrolytes in the small intestine, leading to diarrhea. The presence of ETEC LT in the gut microbiome is an indicator of an active or recent infection.

ETEC is a major cause of traveler’s diarrhea in adults in industrialized countries and a leading cause of infant diarrhea in developing countries. ETEC is estimated to cause 200 million episodes of diarrhea and approximately 380,000 deaths in children in the developing world and travelers to those areas. In the US, ETEC is estimated to cause approximately 17,800 foodborne illnesses annually. Enterotoxins produced by ETEC strains include heat-labile LT toxin and heat-stable ST toxin. ETEC illnesses are usually associated with acute watery diarrhea and sometimes nausea, headache, vomiting, or fever.

O que são eosinófilos?

Os eosinófilos são um tipo de glóbulo branco que ajuda a defender o organismo contra parasitas, alérgenos, bactérias e vírus. Embora representem menos de 5% dos glóbulos brancos, desempenham um papel fundamental na resposta imunológica.

Um nível elevado de eosinófilos pode indicar infecção ou reação alérgica, enquanto níveis muito altos podem ser um sinal de uma condição de saúde subjacente.

O que os eosinófilos combatem?

• Infecções fúngicas, bacterianas e virais
• Parasitas, como vermes

Como os eosinófilos funcionam?

Os eosinófilos destroem patógenos invasores e contribuem para a inflamação, especialmente em alergias, asma e eczema. Embora a inflamação ajude a controlar infecções, também pode causar danos aos tecidos, tornando os eosinófilos tanto protetores quanto agentes em doenças alérgicas.

Eosinófilos e Inflamação

Os eosinófilos estão no centro da resposta inflamatória do corpo, especialmente em casos de alergias. Quando o sistema imunológico identifica uma ameaça, como um parasita ou alérgeno, os eosinófilos liberam substâncias químicas para atacar o invasor. Esse processo desencadeia a inflamação, que ajuda a isolar e controlar a resposta imunológica no local da infecção ou irritação.

Embora a inflamação seja um mecanismo de proteção, ela também pode causar danos aos tecidos ao redor. A inflamação crônica, como a observada em alergias, asma ou eczema, pode levar a desconforto e outros efeitos de saúde a longo prazo.

Eosinophil Activation Protein (EDN/EPX) is a protein released by activated eosinophils which has strong cytotoxic characteristics. 

Cytotoxic means that a substance or process can damage cells or cause them to die. "Cyto" means cell and "toxic" means poison.

The protein plays a significant role in a variety of inflammatory and mast-cell mediated pathologies in addition to fighting pathogens, particularly viral infections.

Eosinophil Cationic Protein (ECP) is a ribonuclease that is part of the RNase A superfamily, primarily associated with the body's immune response mechanisms, especially in the context of allergic reactions and parasitic infections.

ECP is released by eosinophils, a type of white blood cell that plays a crucial role in the body's immune defense system. Eosinophils are known to be involved in the modulation of immune responses and the mediation of inflammatory processes, particularly in allergic conditions such as asthma, rhinitis, and eczema, as well as in responses to parasitic infections.

The presence and concentration of ECP in bodily fluids are used as a biomarker to indicate the activation of eosinophils and the intensity of the inflammatory response. High levels of ECP are often associated with active disease states in conditions characterized by eosinophilic inflammation. For instance, in patients with asthma, elevated ECP levels can reflect the severity of airway inflammation and have been linked to disease exacerbation and decreased lung function. Similarly, in allergic rhinitis and atopic dermatitis, increased ECP levels correlate with symptom severity and the extent of eosinophilic involvement.