Salmonellosis - Causes, symptoms and treatment. MF.

Salmonella is a group of acute infectious diseases, zooanthroponous nature, caused by numerous bacteria of the genus Salmonella and characterized by a predominant lesion of the gastrointestinal tract, resulting in further dehydration, intoxication and attachment of the polymorphic clinic in the future.

The causative agent of salmonellosis

The causative agent was first discovered in the early 19th century in the organs of a deceased person and the meat that he used on the eve. In the future, all diseases with such symptoms began to be combined in the name "salmonella".

Salmonella schematically

Salmonella pathogens, pathogenic to humans, are about 100 species, but the most common are Salmonella typhimurium, S. enteritidis, S. panama, S. infantis, S. newpart, S. agona, S. derby, S. london, S. paratyphi A / B, S. schotmuelleri.

The course and risk of the disease is caused by the following pathogenicity factors:

1. Flagellum( H-antigen) located along the periphery of the pathogen, they cause the movement of

2. The capsule( K-antigen) explains the protection against phagocytes
3. The inferiority of phagocytosis predisposes to the development of sepsis
4. Features of the invasion( penetration) make the penetration of the pathogen almost unobstructed into the glandular tissues of
5. Adhesion( attachment) due to fibrils, pectins, LP-saccharide complex
6. Exotoxin(
- thermolabile exotoxin = enterotoxin, realizes its mechanism of action by activating the cascade of the enzyme system( adenylate cyclase), cAMP is activated - this causes the release of Na and Cl from the cells of the intestine, and after them along the concentration gradientthe water leaves into the intestinal lumen, and so the formation of diarrhea with further dehydration occurs,
- the thermostable exotoxin mediates its action through guanylate cyclase, this entails the phenomenon of fast pancreatitis
- cytotoxin causes damage to epithelial cells
7. Endotoxin is a biologically active substance released after destructive phagocytosis. In this case, endotoxin is a lipopolysaccharide complex and it plays a major role in the formation of intoxication:
- causes delayed and immediate
hypersensitivity - reduces the degranulation of neutrophils and the release of biologically active substances
- activates the synthesis of prostaglandin and thromboxane - it triggers platelet aggregation in small capillaries,develops inflammation, DIC-syndrome( disseminated intravascular coagulation).Prostaglandins in addition, like enterotoxin, stimulate the secretion of Na and Cl, and also causes a reduction in smooth muscles and intestinal motility.

Salmonella are relatively resistant to various environmental factors:

• At room temperature, up to 3 months on household items;
• In dry feces of animals under 4 years;
• In water up to 5 months, in meat and dairy products up to 6 months, on the eggshell up to 24 days;
• High temperatures are practically not harmful, because salmonella practically instantly die only at 100 ° C, at 70 ° for 30 minutes. Resistance to high temperatures increases when the pathogen is in meat products( 400 g of meat with a thickness of 19cm should be boiled for 2.5 hours, only after that meat can be considered safe).Pickling and smoking practically has no effect on salmonella.
• Stability of the pathogen is also noted for low temperatures, down to -80 ° C;
• Resistant to UFI;
• When disinfected, it dies within 20 minutes.

Susceptibility is ubiquitous, without sexual, age and territorial limitations. But the greatest risk of morbidity among children during the year from the moment of birth, due to imperfect immunity. Salmonellosis occurs throughout the year, but sporadic outbreaks are noted more often in the summer months.

Causes of infection with salmonellosis

Source - domestic and farm animals( cattle, pigs), domestic birds( chickens, geese ducks), cats, birds, fish, sick people and bacterial carriers. Transmission ways - alimentary( through eggs, dairy and meat products) and contact and contact-household. Very often, when using eggs for food, they do not pay attention to the changes in the protein and yolk( this can be either a hemorrhage, or a cloudiness, or a musty smell) - it is often infected salmonella eggs, when using which there is an inevitable infection. Therefore, as soon as you notice this during cooking, immediately dispose of this contaminated product and everything that came in contact with it, and the dishes in which you found it, fill with chlorine solution, hand it up with this solution( simple soap is not enough!).

Currently, of all parasites of salmonella are most common for several reasons: due to a centralized food supply system;the development of antibiotic resistance with the formation of hospital strains, which are characterized by winter flares, high lethality and contact-household transmission mechanism as the main one.

Symptoms of salmonellosis

The incubation period is considered from the moment of introduction of the pathogen into the macroorganism before the appearance of the first clinical symptoms, the duration of this period is wide-ranging and can last from 6 hours to 8 days, but in most cases is observed after 12-24 hours from the time of consumption of the infected product.

Entering the gastrointestinal tract, salmonella reach the small intestine, attached to the mucosa by adhesion factors( # 5 in the list of pathogenicity factors, presented above).

The period of clinical manifestations indicates the onset of the action of exotoxin, which is released when penetrating into the glibrous tissues, and there begins the action of phagocytosis( ie, the devouring of the pathogen by the cells of the immune system) and the destruction of salmonella secretes endotoxins, these biologically active substances cause specific symptoms.

But part of the pathogen, due to its resistance to phagocytosis, is spread by lymphogenous and hematogenous pathways( through lymph and blood), causing all sorts of symptoms not only from the stomach and intestines. Depending on what is most compromised in the body, then there is one or another clinical form( gastrointestinal, typhoid, septic, meningic, stunted, subclinical, carrier) - in different forms, the symptomatology prevails.

So, with the gastrointestinal form of , the main support point for endo- and exotoxin is the adenylate cyclase and guanylate cyclase system, therefore the disturbance of water-salt metabolism due to emerging diarrhea, in which the stools is watery, frothy, fetid, withgreens in the form of "marsh mud", with a frequency of 7-10 times a day, for 10 days. For the disease is characterized by an acute onset and, against a background of diarrhea syndrome, note weakness, lethargy, mild abdominal pain( especially in the epigastric region and navel).There is also abdominal tenderness in palpation, its rumbling and swelling. Depending on the severity of dehydration, the following symptoms may join:

• from the cardiovascular system( tachycardia, arterial pressure, muffled heart tone);
• from the side of the central nervous system( headache and dizziness, and in young children, there may be convulsive alertness).

The peculiarity of salmonellosis( not only this form) is that the younger the age, the heavier the disease.

When is typhoid-like , instead of recovering on day 7-10, features characteristic of typhoid fever arise:

• wave-like fever,
• hepatosplenomegaly( enlarged liver and spleen, which is determined by palpation),
• on the body appears a small roseolosa rash on day 7( similarly, as with typhoid fever).

Clinical manifestations last for a long time( 3-4 weeks) and are characterized by a gradual fading of symptoms.

The septic form occurs with IDS( immunodeficiency status) and / or in newborns. Characterized by the spread of the pathogen lymphogenous and hematogenous pathways in various organs and tissues, with the formation of purulent foci in the form of osteomyelitis, arthritis, cholecystitis, etc. This form also begins, ie, with the symptoms of gastroenteritis( diarrhea, abdominal pain - all that was with the GI tract), but subsequently joins exanthem as a petechia( specks), but in severe cases in the form of large hemorrhages andpyoderma.

Already from the first days the central nervous system and cardiovascular system are losing. This form with the flow is more prolonged with frequent lethal outcomes.

When is a meningic form of , salmonellosis proceeds like a septic form, but, unlike it, the only septic focus is the CNS.This is more common in children of different age groups due to the high permeability of the BBB( blood-brain barrier), in this case, cerebral symptoms are attached to gastrointestinal symptoms:

• frequent convulsions due to increased convulsive activity;
• vomiting is not bringing relief;
• in babies, before the closure of the large fontanel( up to 2 years), can be observed its bulging and pulsation;
• there are meningeal symptoms( stiff neck, symptom of Kering and Brudzinsky).

The dilapidated form of salmonellosis is characterized by mild diarrhea syndrome up to 1-2 times a day for 2 days.

The subclinical form and carriage of can be detected only by laboratory methods.

Features of the course in children of the first year of life: a very severe gastrointestinal form with a predominance of symptoms of enterocolitis in the form of severe diarogenic syndrome. In 90% of cases, a septic form is formed and proceeds as a mixed infection. Features of nosocomial salmonellosis: these strains( species) are antibiotic-resistant, with severe course and lethal outcome.

After the transferred disease, postinfectious immunity is formed, but it is type-specific and lasts no more than a year.

Diagnosis of salmonellosis

1. Epidemiological criteria are aimed at identifying the source of infection and identifying contact persons.
2. Clinical characteristics are aimed at the detection and differentiation of leading symptoms( intoxication, diarrhea, hepatosplenomegolia, the presence or absence of generalized forms)
3. Laboratory data:
-UAC: Left,  ↑ HF with shift of formula to the left, ↑ SOE
- The bacteriological method is aimed at detecting the pathogen from biological media( stool, blood, urine, injured organs) and suspicious products. The final results come in 5 days.

Salmonella under the microscope

- Serological method: ELISA, RGA and RNGA( indirect hemagglutination test) - these methods are aimed at detecting antibody titer. The results are ready by about 7 days.

The final diagnosis is competent only if a pathogen is detected.

Treatment of salmonellosis

Together with the treatment of drugs you need a bed rest. Below, treatment will be given in accordance with the national standard, but this is only a schematic representation, in life an individual approach is being carried out taking into account age indices / degree of exsycosis / toxicosis and degree of dehydration.

1. Etropic therapy is aimed at destroying the pathogen and the drugs of choice are: enteric, chlorohinolol, ciprofloxacin, salmonella bacteriophage, sanguiritin.

2. Pathogenetic therapy:
- Rehydration therapy is aimed at the restoration of water-salt metabolism, using the rehydron and trison.
- Detoxification therapy is aimed at eliminating dehydration and, the amount of fluid injected depends directly on the degree of dehydration. In this case, glucose and rheopolyglucin are used.
- Eubiotics and biologics: bactisuptil, linex, acipol, bifidum-lactobacterin.
- Sorbents: Smecta( to remove the products of vital activity of salmonella).
- Fermentotherapy: mezim forte, oraz.
- Antidiarrheal drugs: calcium gluconate, indomethacin.
- Spasmolytics( painkillers): no-shpa or analogues.

Nutrition for salmonellosis

Compliance with diet and table number 4;From the diet exclude foods that irritate the stomach and intestines, dairy products and refractory fats. It is impossible to appoint hungry diets, is fraught with aggravation of immunodeficiency state, and also prevents the slowing down of reporative processes in the digestive tract. From food exclude products that promote the intensification of peristalsis, fermenting processes containing large amounts of coarse fiber: black bread and crackers, whole milk, yogurt, fermented milk, cream, whole milk porridge, legumes, beets, cucumbers, sauerkraut, radish, radish, citrus fruits, pears, plums, grapes, meat and fish broths, fatty meats / fish / poultry, as well as all spicy and spirits.

Rehabilitation and prevention

The following methods can be attributed to non-specific prophylaxis: the duration of stay in a hospital with a localized form is 14 days, with a generalized one, up to 30 days. After the end of treatment, bacterial examination is carried out after 2 days, twice and, if the results are negative, the patients are allowed to work. Workers of the food industry are subjected to medical examination for a period of up to 3 months with a monthly single examination of feces - with positive results, they are not allowed to work for 15 days and are assigned to another job, and 5-fold examination of stool and single bile is carried out in parallel if the bacterial release lasts more than 3months - transferred to another job for 1 year with a parallel examination of feces 1 time in a half year, and after the expiration of this year, a fivefold examination of the stool and one-timee study of bile with an interval of 1-2 days, with a new positive result - removed from work, and with a negative - removed from the account and returned to the workplace.

Along with these measures, veterinary and sanitary supervision in the areas of livestock maintenance, technology of processing / storing / cooking carcasses is reinforced. And they also monitor sanitary surveillance at food enterprises for control of machinery and quality of preparation.

For prophylactic purposes it is necessary to boil meat and eggs well, observe personal hygiene.

Specific prophylaxis: not developed, because it is based on the principle of vaccination, which is created by neutralizing virulent strains - this is impossible in this case, because more than 2,500 virulent strains exist.

Complications of salmonellosis

Numerous and diverse:

• Vascular collapse with the formation of acute cardiac and renal insufficiency;
• Septic complications with development of purulent foci in various organs and tissues, and as a result of this: arthritis, osteomyelitis, endocarditis, brain abscess, spleen, liver and kidneys, meningitis, peritonitis, appendicitis, pneumonia, urinary tract infections, infectious-toxic shock.
• The most dangerous complication for others is carriage, which is formed due to incomplete phagocytosis.

The disease is deadly.

Therapist doctor Shabanova I.Е.