E. coli patterns in newborns

E. coli patterns in newborns

 E. coli patterns in newborns

 
Mrs. Ola Jamil Jubeir Qawam Al-Din
 
 
Intestinal bacteria naturally arise in the alimentary canal a few days after birth, making up the normal flora in the intestine, and Escherichia coli is the main part of it. The appearance of bacteria in their intestines, for some children, the appearance of bacteria in their intestines begins 24 hours after birth and is delayed in others (Bischoff et al., 2002).
An illustration of coliform bacteria in the human intestine
 
Some studies have reported that E. coli was isolated from the feces of healthy children, so it was considered non-pathogenic, but some of its strains have the ability to become opportunistic and cause various diseases when they leave the original site (intestines) and reach other organs in the abdominal cavity, especially when appropriate conditions are available, such as weak immunity, so E. coli is one of the most important main pathogens, especially in hospital infections, as it causes many diseases when it enters the bodies of people in convalescent homes (Jawetz, et al., 2004; Cookes, 1985).
 
E. coli bacteria contribute greatly to cases of diarrhea in infants, and it has been divided into several strains that cause diarrhea in the digestive system and others capable of causing disease in sites outside the digestive system. The pathological groups include both enteropathogenic E. coli, and E. coli hemorrhagic Enteroinvasive E. coli, Enterotoxigenic E. coli, Enteroinvasive E. coli Enteroaggregative E. coli, Diffuse serogroup of E. coli is responsible for the identification of Adherence. Aetiology (Bueris et al., 2007; Kapar et al., 2004; Mulla et al., 1999;).
 
Some research reports that Escherichia coli is one of the most important bacteria that causes diarrhea in childhood. Diarrhea Escherichia was considered the most common cause of morbidity and mortality among infants and children, especially in developing countries, and it causes more than 85% of UTIs than other pathogenic bacteria (Levine et al., 1987).
 
Studies have shown that it is not possible to determine the serotypes that cause diarrhea and other diseases in infants based on the agricultural and biochemical characteristics, due to the difficulty of distinguishing them from the nonpathogenic E. coli that occurs naturally in the normal human stool, because the serotypes are not always associated with The pathogenesis, and the technique of polymerase chain reaction (PCR) has been used as a precise technique through which it is possible to identify the presence of genes encoding the pathological virulence factors carried by serotypes that help them in causing disease and through which the serotype can be diagnosed, as epidemiological studies in countries have proven Developing on children The most common strains of E. coli isolated from children less than one year old are EPEc, ETEc and EAEc (Theresa et al., 2009; Spano et al., 2008; Porat et al., 1998; Levine et al.,1993)
 
 
 
 
 
The modern classification of E. coli can be described as follows (Castellani and Chalmers, 1919):
 
Scope: Bacteria
 
Phylum: Proteobacteria
 
Class: Gammaproteobacteria
 
Order: Enterobacterialas
 
Family: Enterobacteraceae
 
Gender: Escherichia
 
Type: Escherichia coli
 
 
 
Bacterial patterns:
 
Escherichia coli bacteria were divided according to the site of disease into inflammatory strains within the intestinal tract and others capable of causing disease in sites outside the intestinal tract Kapar et al., 2004; Mulla et al., 1999)).
 
 Escherichia coli causing intestinal infections: E. coli is one of the most important bacteria causing diarrhea in childhood (Levine et al., 1985). It causes 30-40% of acute diarrhea in children (O'Ryan et al., 2005).
 
Diarrhea is the presence of at least three soft or liquid bowel movements every day, and it often leads to dehydration due to fluid loss due to its continuation for several days. Constipation per day or liquid stool with blood. Signs of dehydration include loss of the normal stretching of the skin and nervous behavior, lack of urination, loss of skin color, rapid heart rate and a decrease in response as it becomes more severe. Or a bacteria or parasite, a condition known as gastroenteritis, and this infection is acquired from food or water contaminated with feces or directly from one infected person to another (W.H.O., 2013; Morris et al., 1994).
 
There are bacterial, parasitic, or viral causes that can cause diarrhea and there are non-infectious causes including lactose intolerance, irritable bowel syndrome, non-celiac gluten sensitivity, inflammatory bowel disease, celiac disease, hyperthyroidism and a number of medicatiThere are bacterial, parasitic, or viral causes that can cause diarrhea and there are non-infectious causes including lactose intolerance, irritable bowel syndrome, non-celiac gluten sensitivity, inflammatory bowel disease, celiac disease, hyperthyroidism and a number of medications in most Cases (Moon et al., 2015; DuPont, 2014; W.H.O., 2013; Basem and John, 2013; Sapone et al., 2012), and among the Diarrhea E coli bacteria that cause endemic and endemic diarrhea throughout The World (Nataro and Kaper, 1998). The DEC strains can be classified into six main strains on the basis of their virulence characteristics and different epidemiological and clinical characteristics, differing in the world from one region to another and even between and within countries in the same geographical region (Al_Gallas et al., 2007; Nguyen et al., 2005 ), in Nicaragua, EnteroPathogenic Escherichia coli (EPEC) and EnteroToxigenic Escherichia coli (ETEC) were found to be associated with diarrhea in Africa in children under 6 years of age, and children under 2 years of age were most affected, and in a multiple study conducted in Steele, EPEC was found to be more frequent in children with diarrhea (16%) than in healthy children (4%), however ETEC rates were not significantly different (28 cases and 16% were infected), and in a study Conducted in Lyon, ETEC was found in 38% of diarrhea cases in 1996, and this study largely exemplifies the difference in the prevalence of two types of DEC within the same country, as epidemiological studies in developing countries on children demonstrated that the most common strains of E. coli isolated from children which The fact that their age is less than one year only is (EPEc, ETEc and EAEc) (Theresa et al., 2010)).
The studies aimed to determine the relative prevalence of six types of E. coli that cause diarrhea in children under the age of 5 years (Mayatepek et al., 1993; Paniagua et al., 1997). About 1.6 to 5 billion cases of diarrhea occur annually, and the total deaths from diarrhea are estimated at 1.26 million in 2013, while the number of deaths was 2.58 million in 1990. In 2017, diarrhea was the second most common cause of death among children under five years of age. The death rate was 5.6 million compared to 2016, when the number of deaths reached 9.9 million children (W.H.O., 2017). Some studies have shown that malnutrition is a major cause of most cases of recurrent diarrhea in those under the age of five years, and it can produce other long-term health symptoms. Like stunted growth and poor intellectual development, diarrhea has become a major public health problem in developing countries and the second most important underlying cause of disease and death worldwide, as this disease causes the death of 760,000 children every year. Contaminated drinking water that carries many germs, as a child under the age of three suffers from three episodes of diarrhea (short-term diarrhea, long-term diarrhea, and bloody diarrhea), and each attack deprives the child of the nutrition necessary for his growth, so it is considered Hal is one of the most important causes of malnutrition, and in turn, children who (and John, 2013; Kosek et al., 2003).
1- Enterohaemorrhgic E. coli: It was also known as Vero toxin producing Escherichia coli for the first time as a cause of bloody diarrhea and human hemolytic uremic syndrome (HUS in 1982 when two epidemic cases of hemorrhagic colitis were recorded) Hemorrhagic Colitis (HC), which was associated with eating undercooked hamburgers in a fast food restaurant in America, and the diagnosis results showed that the cause is one of the EHEC bacteria strains that infer from the Stx-positive strains that contain specific pathogenicity islands called Locus of enterocyte effacement (LEE), All factors that lead to HUS are unknown except for Shiga-toxin, which is also called (vero toxin) plays an important role in the occurrence of renal injury (Welch, 2006).
This EHEC strain was known when epidemic cases of hemorrhagic colitis occurred. This infection develops as mild diarrhea not associated with blood into bloody diarrhea, and in some cases the infection extends to uremia thrombotic. These organisms share the ability to cause infections in the upper respiratory tract with EPEC. However, Escherichia coli EHEC is isolated from EPEC by A/E_ the lesions, children under five years of age are the most affected age group with this EHEC strain in addition to the elderly also may show bloody diarrhea and HUS_EPI, this strain caused a great problem in Europe, Japan and North America And in southern Africa, unpasteurized milk, undercooked hamburgers, and apple juice prepared from apples contaminated with cow manure manure have also been associated with swimming in a crowded water tank and drinking chlorinated water (Kawano et al., 2012; Welch, 2006).
The serotype H7:O157 is most common in strain EHEC, but serotypes O111, O26 cause similar diseases, and strains O114, O142, O124 obtained from E. coli isolates of poultry hatcheries (Babai and Mohammed, 2005).
2: Enterotoxigenic Escherichia coli: It is the strains that cause diarrhea and dehydration in infants in hot countries with poor health. This strain adheres to the cells of the small intestine and multiplies on its surface and excretes toxins, which leads to a severe imbalance in the lining of the intestine and severely affects the intestines. Mechanisms of emptying and absorption, these strains are the cause of diarrheaons in most Cases (Moon et al., 2015; DuPont, 2014; W.H.O., 2013; Basem and John, 2013; Sapone et al., 2012), and among the Diarrhea E coli bacteria that cause endemic diarrhea in all2: Enterotoxigenic Escherichia coli: It is the strains that cause diarrhea and dehydration in infants in hot countries with poor health. This strain adheres to the cells of the small intestine and multiplies on its surface and excretes toxins, which leads to a severe imbalance in the intestinal lining and severely affects the intestines. The mechanisms of excretion and absorption, these strains are the cause of frequent diarrhea in humans and animals alike, as this strain causes 600 million cases of diarrhea and 800,000 deaths annually worldwide in children under the age of five in developing countries, contaminated weaning food is the main cause of infection Infants, contaminated water and hands contaminated with faeces through contact is one of the rare causes of infection (Welch, 2006; W.H.O., 1999).
This strain is the most important cause of diarrhea for travelers that affects those coming from industrialized countries to hot areas. ETEC causes watery diarrhea that can be mild in nature or sometimes be severe, like symptoms of cholera, as it causes rapid dehydration that can lead to death, and in Endemic areas Diarrhea is the main cause of travelers' diarrhea in adults who visit endemic areas (Welch, 2006).
The reason for the danger of this strain is due to its possession of virulence factors such as heat_labile enterotoxin (LT), which is similar in structure and function with the toxins secreted by cholera, in addition to the enterotoxin LT secreted by ETEC heat_stabile enterotoxin strains, which also contribute to the occurrence of watery diarrhea, which is Toxins STa, STs and STb strains of ETEC Children and infants under 5 years of age are the most affected by it. The incubation period of these bacteria for the onset of symptoms of the disease is estimated to be less than 10 - 12 hours, which is abdominal cramps, acidosis, fatigue, dehydration and a slight rise in the temperature Heat and symptoms last for less than 5 days (Welch, 2006; Sixma et al., 1993; Spangler et al., 1992).
The most important strains belonging to this group, which were found in isolates that cause diarrhea in humans, are O157, O111, O104 (Benenson, 2011), and there are also other strains isolated from diarrhea isolates, namely O26, O103, O113, where these strains possess virulence factors represented by unstable toxins. Heat_ labile toxin Heat_ stable toxin Adhesive factors CFAI, CFAII and E8775 that help in causing injury (Nataro and Kaper, 1998).
3: Enteroinvasive Escherichia coli: It is the strain that causes inflammation of the mucous and submucosal layer of the intestine, and it is a strain that is able to invade the colonic epithelial cells of the large intestine and spread from one cell to another, which causes inflammatory reactions that result in ulcers, which may cause Sometimes dysentery (Nataro and kaper, 1998). Symptoms caused by this strain include severe abdominal cramps, malaise, watery stools, tenesmus and fever, and 10% of cases develop into liquid stools that contain blood and mucus frequently and little and contain a quantity of white blood cells. Symptoms of disease appear 18 hours after ingestion of contaminated food. These pathogenic bacteria are closely related to ETEC. There are few biochemical characteristics that can be used to distinguish between ETEC and EIEC, as EIEC isolates 70% of them are not lactose-fermenting, in addition to their inability to analyze carboxylates (Silva et al., 1980).
EIEC causes colitis and inflammatory dysentery with clinical symptoms (blood, mucus, stool accompanied by fever and severe cramps) (Welch, 2006). Several genes that encode for virulence factors that aid in cell invasion and cause various seizures are found on a large plasmid <200kb) in EIEC, and interestingly, their inability to produce DE-carboxylate lysine is a common trait between EIEC and ETEC which is the result of mutations and gene rearrangements. in the cad C gene (Casalino et al., 2003).
Plasmids carry an important type III secretion gene system that receives signals from the host cell for membrane analysis. A role in the spread of bacterial cells to other host cells (Welch, 2006).
This group possesses many serotypes that have a high ability to adhere to the epithelial cells of the intestine and possess high levels of toxins, the most important of which are O28ac, O29, O124, O136, O143, O144, O152, O164, O167, O86, O119, O127 (Nataro and Kaper, 1998).
4: Enteropathogenic Escherichia coli: It is the strains that cause diarrhea of ??different severity, causes inflammation of the intestinal epithelium and microvilli, the cells of the gastro-intestinal coli, and this bacteria is an important cause of infection in infants in developing countries, this bacterial group caused summer epidemics in In the years 1940 and 1950 in infant centers, nurseries and maternity homes, this bacterial group caused diarrhea in infants who did not exceed one year of age (W.H.O., 2014). EPEC causes watery diarrhea that may contain mucus but usually no blood. Clinical symptoms include vomiting, fever, malaise, and dehydration. Symptoms may last for a short period of several days, to prolonged periods, and may be a chronic condition that may cause a high rate of Mortality: Infection occurs with contaminated feeding and weaning foods, incubation period of less than 9-12 hours (Welch, 2006).
. has been identifiedEnterocoliform (EPEC) genes have been identified based on serotypes such as O55:H6, O127:H6, and there is a great diversity of E. coli serotypes that possess these characteristics, and they are classified as atypical EPEC (Trabulsi et al., 2002).
The diarrheal EPEC strain that causes attachment and effacing lesions (A/E) on the intestinal epithelium, but lacks Vero toxins, has been known. The result of a complex system of proteins that the strain injects into the epithelial cells of host cells results in diarrheal pathogen serotypes containing specific pathogenic islands called locus of enterocyte effacement (LEE) that encode the genes responsible for the A/E lesion. Most EPEC strains share EPEC adherence factor plasmids (EAF) that encode for adhesion factors and results from human voluntary studies indicate the presence of these disease-inducing plasmids. , This strain was eliminated in the late sixties as a pathogen in North America and Europe, but it is still one of the most important causes of diarrhea events in southern America, Africa and Asia (Behrman et al., 2016; Levine et al., 1987).
This group is considered one of the most important groups of Escherichia coli, which contains many serotypes that invade intestinal cells and cause diarrhea. They are O26, O55, O86, O111, O114, O119, O125, O127, O128, O142, O158, in addition to serotypes that play an important role in causing diarrhea in children, the most important of which are O2: H2, O2: H25, O15: H2 (Albert et al. ., 1993).
5: Enteroaggregative Escherichia coli: These strains were defined as E. coli strains HEP_2 with a pattern called auto aggregative (Nataro and Kaper, 1998). This strain is considered the largest cause of persistent diarrhea in infants, as this strain has been associated with an increased cause of diarrhea in children in developing countries with diarrhea lasting more than 14 days, EAEC was defined by its ability to enter into epithelial cells distinct pattern, as the spores of this strain By sticking to the intestinal cells and forming a thin and compact layer of mucus on them, which is the main cause of death or disease, it is a cause of watery diarrhea caused by strains of E. coli belonging to this class, which are often persistent and can be inflammatory, or this strain may be associated with intermittent diarrhea in Children and adults in both developing and developed countries, and it has been identified as the cause of the outbreak of many diseases worldwide, as this strain was observed accompanying persistent diarrhea in India, and persistent diarrhea is diarrhea that cannot be controlled before the passage of at least two weeks, as it was observed In Mexico, Bangladesh, Congo and Brazil and cases in the United Kingdom and Germany, it causes a few cases in industrialized countries (Nataro et al., 1998).
The aetiology of EAEC strains is poorly understood, although several factors of virulence have been used to diagnose this strain. EAEC strains encode “Aggregative adherence fimbriae” (AAF), EAEC isolates frequently produce the “Pic” gene that has the ability to encode the DNA of a gene similar to the one encoding enterotoxin, EAEC strains produce heat_stable endotoxin “EAST1” is similar to the toxins produced by ETEC “ST1” strains, the O126 strain is the most important serotypes belonging to this group, in addition to the O111, O42 strain that researchers isolated from human diarrhea (Mohammad zadeh et al., 2016; Welch, 2006).
Adherence Escherichia coli: It is the strains that have the ability to stick and is considered the last group that was discovered after other groups, and it can infect infants and school children, a distinct pattern is defined from the patterns to HEp_2 cells (Nataro and Kaper, 1998). The name of this strain is derived from its special characteristic which is the adhesion to cells mediated by fimbria_mediated. E. coli is the most important cause of urinary tract infection because of its stability in the digestive system. (Johnson et al., 2001a; John et al., 2001b; Peeters, 1994). The global epidemiological statistics of children with urinary tract infection who are treated in the hospital amounted to 40,000 children annually, and the infection rate is 1% for females and 3% for males in the first year and after birth, 2% for children less than three months old and 5% for children. Those whose age is more than three months, male children, especially children who have not undergone circumcision, whose age is less than a year and immediately after birth, are exposed to urinary tract infection (W.H.O., 2010).
The most important bacteria that cause UTIs are Escherichia coli 68% and possibly more, isolated serotype O18:K1:h7 from UTI cases: Proteus mirabilis 12%, Klebsiella aerogenes 4%, Enterococcus faecalis 6%, Staphylococcus epidermis or Staphylococcus saprophytics 10 , be bacteria K. aerogenes and E. faecalis are the most prevalent in hospitals and cause urinary tract infection in children, other causes of inflammation are congenital anatomical abnormalities, stones in the urinary system increase the possibility of infection with these diseases, E. coli causes 85% of urinary tract infection in infants, especially Females of them, due to the shortness of the urine canal, are more likely to get a urinary tract infection because of the presence of these bacteria naturally in the intestines, on the skin, and around the rectum or vagina in females. Especially children under the age of one year (Corinne et al., 2007)).

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