neonatal epidemic diarrhea
Introduction
Introduction to neonatal epidemic diarrhea Epidemic diarrhea (epidemicdiarrheaofnewborn) refers to the outbreak of epidemic diarrhea in the maternity babies or hospital neonatal wards. Due to impaired immune function and environmental factors, infections are prone to occur. The pathogens are more common in bacteria, viruses, fungi, and parasites, and are mainly transmitted through the mother's birth canal, contaminated dairy products, water, nipples, food utensils, and adult carriers. basic knowledge Sickness ratio: 0.05%-0.08% Susceptible people: infants and young children Mode of infection: digestive tract spread Complications: dehydration, metabolic acidosis, thrush, diaper dermatitis, pneumonia, sepsis, anemia
Cause
Neonatal epidemic diarrhea
(1) Causes of the disease
1. Bacteria are more common with Escherichia coli, pathogenic Escherichia coli (EPEC), toxic Escherichia coli (ETEC) and hemorrhagic Escherichia coli (EHEC) have had neonatal epidemics Sexual diarrhea, especially EPEC is a common cause, epidemic, sometimes can cause the epidemic of infant diarrhea in the whole ward, and even spread to the hospital, causing the prevalence of babies in the whole region. The first case of the epidemic began, mostly from the delivery of pregnant mothers. Before and after diarrhea, or Escherichia coli in the cervix, newborns get infected during childbirth, may also get infection from mother after childbirth, 1 to 6 days after birth, first transmitted to newborns near the baby room Children, the scope has gradually expanded to become popular, another way of transmission has been direct or indirect contact with neonates with epidemic diarrhea, or indirectly infected from the hands or carriers of the staff, but still in the incubation period, as normal The baby was discharged from the hospital, and diarrhea occurred shortly after returning home. He was taken to the neonatal ward of another hospital, causing diarrhea in the hospital.
Salmonella typhimurium is also an important pathogen of epidemic diarrhea. Rat typhoid bacteria are widely distributed, causing diseases to humans and certain animals. The rate of infection is high after recovery. Therefore, there are many sources of bacteria, high incidence, and diarrhea. Carriers or patients from pregnant women or staff members have reported that the nasal cavity of the staff can also carry bacteria and pass the medium to the newborn. Therefore, in the place where the incidence of typhoid fever is high, special attention should be paid to the prevalence of neonatal diarrhea, neonatal infection. The post-bacterial rate of Salmonella is higher than that of children or adults. Therefore, neonatal patients should have multiple stool cultures after diarrhea control, and can be discharged after at least 3 consecutive negatives.
Other bacteria, such as Campylobacter jejuni, Yersinia, Aeromonas, Pseudomonas aeruginosa, Staphylococcus aureus, Shigella, aerobacteria, halophilic bacteria can also cause neonatal diarrhea.
2. Viral rotavirus is one of the most common pathogens causing neonatal epidemic diarrhea. It is mainly transmitted through the faecal-oral route. Healthy adults can be used as carriers. Infected newborns are also important infectious agents. Rotavirus is in the environment. It is relatively stable and difficult to inactivate naturally. It can be transmitted by nursing staff. It is also reported that rotavirus can pass through the respiratory tract and placenta, but rotavirus can be found in the stool. It can not be considered as the pathogen of diarrhea. It can also be found in normal stool. The virus, in the epidemic, such as the nucleotide or gene configuration of rotavirus in most children's stools, can be considered as a common cause, Coxsackie virus, Echo virus, intestinal adenovirus, etc. Causes neonatal epidemic diarrhea.
3. Fungi can be used for secondary fungal infections for a long time. Candida albicans is more common.
4. Parasitic trichomoniasis, Piriformis, stealth sporozoites, etc. can also cause neonatal epidemic diarrhea.
(two) pathogenesis
According to whether the pathogen causes an inflammatory reaction in the intestinal wall, the pathogenesis is divided into two categories: non-inflammatory (intestinal type) and inflammatory (mucosal type).
1. Non-inflammatory type is also called intestinal cavity type. The invasive part is mainly in the small intestine. The main manifestation is watery diarrhea. The mechanism is the reduction of intestinal toxin or intestinal wall absorption area. The representative pathogen is toxic Escherichia coli, rotavirus. And Aeromonas.
Toxigenic Escherichia coli can produce two enterotoxins, there are three types of strains, one is heat-labile enterotoxin (LT); one is heat-resistant enterotoxin (ST); the other is simultaneous production LT/ST strain of heat-resistant enterotoxin and heat-resistant enterotoxin, LT is a protein that converts intracellular adenosine triphosphate (ATP) into a cyclic phosphate gland by activating adenylate cyclase on the intestinal epithelial cell membrane. Glycoside (cAMP) causes a large amount of water and electrolyte to excrete from the small intestine of the epithelial cell membrane of the intestinal wall to cause watery diarrhea. ST is a polypeptide whose mechanism of action is different from that of LT, which activates guanylate cyclase on the cell membrane. Increasing the level of guanylate adenosine (cGMP) in the cells causes an increase in intestinal secretion and diarrhea occurs. The secretion of disaccharidase is reduced, and secondary disaccharide malabsorption occurs, which delays diarrhea.
The pathogenesis of rotavirus enteritis is currently believed to be the target enzyme of the virus on the outermost surface of the small intestine villi. The virus invades the intestinal epithelial cells of the distal brush border of the villus and propagates within the cell, causing microvilli in the epithelial cells to occur. Breaking, fusion, disappearance, etc., causing local enzymes involved in mucosal digestion, especially lactase activity, causing absorption dysfunction leading to diarrhea.
2. Inflammatory type is also called mucosal type. The invading site is mainly in the colon, invading the intestinal mucosal epithelial cells, and in the cells, causing inflammation, even ulcers, manifested as dysentery-like diarrhea, representative pathogens have Shigella, Salmonella typhimurium Phase ETEC, Shigella produces enterotoxin in addition to increased intestinal secretion, but also can cause acute inflammation of the lamina propria of the intestinal wall, micro-ulcer formation and pus, bloody exudate, Salmonella typhimurium in addition to invasive, but also It can produce cholera-like enterotoxin, causing ileitis, colitis, and abnormalities in water and electrolytes. The pathogenesis of ETEC is similar to that of Shigella, and its membrane surface contains colony factor antigens CFAI and CFAII regulated by plasmids to promote bacteria. Adhesion ability.
ETEC also has the ability to adhere to the small intestinal mucosa, and can produce a similar kind of Shigamycin, which shows cytotoxicity, neurotoxicity and intestinal toxicity, intestinal toxicity can increase intestinal secretion, ETEC infection It can also reduce the secretion of intestinal disaccharide-degrading enzymes, causing secondary disaccharide malabsorption, and delaying the diarrhea.
ETEC is a diarrhea-causing Escherichia coli that has been found in recent years to produce a Shigella type I cytotoxin that causes hemorrhagic colitis, called enterohemorrhagic Escherichia coli enteritis.
Prevention
Neonatal epidemic diarrhea prevention
The prevention of neonatal epidemic diarrhea is mainly to disinfect and isolate patients to cut off the source of infection. Once neonatal diarrhea is found, the child and its parents should be immediately isolated and actively treated. If the epidemic is difficult to avoid, it will be directly Or indirectly contacted babies are concentrated in a ward, daily stool culture, close observation of diarrhea, and concentrated isolation of stool-positive people.
Some authors believe that those who have positive stool culture, with or without diarrhea, are given antibiotics for 5 days, but there are also anti-drug prevention, because the drug-preventing rate is higher, the symptoms may be delayed, and sometimes the symptoms may be recurrent. Increase the popularity time.
Infants with diarrhea epidemics should be quarantined, no new babies or new patients should be collected, and the rehabilitated babies should be brought together. The stool culture was discharged three times and then discharged. The newborns who did not have diarrhea were also concentrated in one, after the incubation period ( 1 to 6 days) After the stool culture is negative for 3 times, it can be discharged. After any sick child is discharged from the hospital, the supplies on the original bed, such as bedding, sheets, pillows and beds should be disinfected.
The baby room and the ward should be disinfected every day during the epidemic, the floor is wet, the furniture is wet, the dust is not allowed to fly, and the air, floor, wall and furniture swabs are regularly cultured.
The staff should pay special attention to the brushing of the hands. After each child is touched, the hands should be washed before touching the other baby. Regular hand swabs, nasal swabs and stool culture. The positive ones should be removed from the hospital or baby room. Wear sterilized gloves and then put on the nipples. The diapers and sheets that are contaminated with feces should be collected together and sterilized before being sent out of the ward.
Complication
Neonatal epidemic diarrhea complications Complications dehydration metabolic acidosis thrush diaper dermatitis pneumonia septic anemia
Dehydration, acidosis, shock and peripheral circulatory failure, neonatal infectious diarrhea often coexist with other infections, or prolonged unhealed causes nutritional disorders and other various infections, common complications are diaper dermatitis, thrush, urinary tract infection , otitis media, pneumonia, sepsis, necrotizing enterocolitis, malnutrition, malabsorption, hypokalemia, hypocalcemia, hypomagnesemia, multivitamin deficiency (including vitamin K), anemia, etc.
Symptom
Symptoms of neonatal epidemic diarrhea Common symptoms Diarrhea mucus dehydration bloating is foamy, odorous, loose, appetite, lack of water, hyponatremia, hypokalemia, skin pattern
1. Gastrointestinal symptoms Diarrhea several times or more than 10 times a day, stool characteristics related to the pathogen, can be a thin watery stool, mucus, bloody stool, children often have loss of appetite, bloating, vomiting.
Neonatal epidemic diarrhea caused by different pathogens has certain characteristics:
(1) Escherichia coli enteritis: pathogenic Escherichia coli enteritis stool is watery, egg-flower soup, smelly; toxic Escherichia coli enteritis stool is a dilute water; invasive Escherichia coli Intestinitis stools are mucus pus and bloody, with a stench and a small amount of stool.
(2) Salmonella typhimurium enteritis: stool characteristics change, can be watery, sticky samples, black-green or gray-white, with obvious odor.
(3) Rotavirus enteritis: acute onset, often fever, stool water, a large amount, the odor is not obvious.
(4) Staphylococcus aureus enteritis: the stool is mostly yellow-green, dark green, watery, with a stench.
(5) Fungal enteritis: The stool is yellow-green and watery, or tofu-like, with more foam.
2. Systemic symptoms often have fever, mental languid, crying and uneasy, severe cases of lethargy, pale, cyanosis.
3. Water, electrolyte balance disorder Newborn diarrhea often occurs in a short period of time, such as dehydration, acidosis, hyponatremia, hypokalemia and other complications, severe facial gray, skin pattern, cold limbs, less urine, Shock occurred.
4. Some other children are accompanied by other parts of the infection, such as pneumonia, otitis media, urinary tract infection, thrush, sepsis and so on.
Examine
Examination of neonatal epidemic diarrhea
Bacterial enteritis, the positive rate of early stool culture is higher, suspected rotavirus enteritis, can do stool smear electron microscopy or patient serum complement binding test, or test antibodies, antigen.
Neonatal diarrhea leads to electrolyte metabolism or acid-base balance disorder and lacks typical clinical manifestations. Therefore, blood gas should be measured in time, blood biochemistry or electrocardiogram should be observed to observe hypokalemia, and timely correction should be found.
Those suspected of sepsis or purulent meningitis or urinary tract infection should be promptly examined, cultured and tested for drug susceptibility. If secondary lactose (or other disaccharide) malabsorption occurs, the reduction in fresh stool can be measured. substance.
1. ECG can have hypokalemia when there is hypokalemia.
2. When the chest X-ray has pneumonia, do a chest X-ray examination in time.
3. B can be done when necessary.
Diagnosis
Diagnosis and differentiation of neonatal epidemic diarrhea
Diagnostic criteria
1. History and prevalence should be detailed in the medical history, understand the epidemiological situation, and help diagnose.
2. Clinical manifestations should be observed in detail in stool characteristics, while observing the development of the disease, the degree of neonatal dehydration is difficult to estimate, especially for premature infants, less subcutaneous fat, using skin elasticity to estimate dehydration is not accurate, preferably according to continuous weight record , urine volume measurement.
3. The pathogen examination should keep the specimens in time for bacterial culture. If the rotavirus infection is suspected, the virus antigen should be checked at the same time. If fungal infection is suspected, fungal spores and hyphae can be seen in the stool.
4. Blood gas analysis and electrolyte examination Neonatal diarrhea is prone to acidosis and electrolyte imbalance, blood gas analysis and electrolyte examination should be done in time to achieve timely treatment.
Differential diagnosis
Infection and non-infectious diarrhea are easily identified according to clinical signs of infection, intestinal infectious diarrhea and extraintestinal infectious diarrhea. The former has severe diarrhea symptoms, the latter is only symptomatic diarrhea, and there is a manifestation of primary infectious diseases. Identification, neonatal epidemic diarrhea can be diagnosed based on epidemiological history and laboratory tests.
Intestinal infectious diarrhea
(1) Epidemiological history: According to the characteristics of medical history, the infants have diarrhea epidemic, suggesting the presence of Escherichia coli, Salmonella typhimurium, Proteus or viral enteritis. The mother has fever and early water breakage. Longer labor or history of asphyxia, etc., should consider the possibility of infectious diarrhea.
(2) clinical manifestations: according to the characteristics of symptoms and signs for differential analysis, early diarrhea, abnormal body temperature, fever or hypothermia, poor complexion, vomiting, stool containing mucus or pus, microscopic examination of red, white (pus) blood cells Indications for infectious diarrhea, further smear staining examination, culture or virus isolation, can identify the nature of enteritis (pathogen).
2. Intestinal infections have symptoms of infection and poisoning. There are primary infectious diseases, and there are a few white blood cells in the microscopic examination.
3. Non-infectious diarrhea, such as digestion and absorption of sugar, fat digestion and absorption, no infection.
