Food Poisoning

Symptoms

The incubation period of toxic infection rarely exceeds several hours, but in some cases it can be shortened to half an hour or extended to a day. Although the causative agents of toxicoinfection are quite diverse, the clinical picture during infection is usually similar. The onset is usually acute, with bouts of nausea and repeated vomiting . Characterized by enteric diarrheawith a frequency of bowel movements 10 times a day or more. There may be abdominal pain of a cramping nature, fever (usually lasts no more than a day), signs of intoxication (chills, body aches, weakness, headache). Rapid fluid loss with vomiting and feces leads to the development of a dehydration syndrome. Patients are usually pale, the skin is dry, the extremities are cold. There is pain on palpation in the epigastrium and near the navel, tachycardia , arterial hypotension. The disease usually lasts no more than 1-3 days, after which the clinical symptoms subside.

There are some features of the course of toxic infection, depending on the nature of the pathogen. When staphylococci are affected, a rapid acute onset is noted, gastrointestinal symptoms predominate, the temperature may remain normal or reach subfebrile numbers, and diarrhea may be absent. From the very first hours of the disease, convulsions and cyanosis of the skin can be noted, but most often the acute clinic lasts no more than 1-2 days and does not cause serious disturbances in water and electrolyte homeostasis. The clostridial lesion is similar to that of a staph infection, but it is more common in the large intestine with diarrhea and blood may be present in the stool. Fever is usually not noted. Proteus toxicoinfection is distinguished by fetid feces.

Toxicoinfections usually proceed quite briefly and do not leave consequences. In rare cases: in severe cases in persons with a weakened body, dehydration shock, sepsis , acute cardiovascular insufficiency may develop.
 

Causes

The causative agent of a food infection can be microorganisms of various genera: Klebsiella, Enterobacter, Citrobacter, Serratia, Enterococcus, etc. These bacteria are very common in nature, in the vast majority they are part of the normal human intestinal biocenosis. Since the clinical picture of toxic infection develops as a result of exposure not to the microorganisms themselves, but to the toxic products of their vital activity, the pathogen as such is often not isolated. Conditionally pathogenic bacteria are able to change their biological properties (resistance to antibiotics and disinfectants, virulent characteristics) as a result of exposure to environmental factors.

The source and reservoir of infection are usually people and farm animals, birds. Most often these are persons suffering from diseases of a bacterial nature with active release of the pathogen ( purulent diseases , tonsillitis , furunculosis ), dairy cattle with mastitis . A healthy carrier can also become a source of infection. For some genera of bacteria that can cause food poisoning, soil and water, environmental objects contaminated with animal and human feces can serve as a reservoir.

Toxicoinfections are transmitted by the fecal-oral mechanism, mainly by food. Microorganisms get into food products, where they actively multiply and accumulate. Food poisoning develops when a person eats foods that have formed a high concentration of microorganisms. Toxic infections in the vast majority of cases occur when eating animal products: meat, dairy products, confectionery with fatty creams, fish. Meat and semi-finished products from it (minced meat) are the main source of clostridial infection. Some methods of preparing semi-finished products and dishes, storage and transportation conditions contribute to the germination of spores and the reproduction of bacteria. For products affected by staphylococci, characterized by the absence of visible and taste differences from normal food. Various objects and objects, water sources, soil, dust can take part in the transmission of infection. The disease is characterized by seasonality: in the warm season, the frequency of toxic infections increases, since the air temperature contributes to the active reproduction of bacteria. Toxic infections can occur both in the form of individual cases in everyday life, and outbreaks with organized meals in groups.

The natural susceptibility of people to these infections is high, as a rule, everyone who has eaten foods affected by microorganisms falls ill with varying degrees of severity. Persons with weakened protective properties of the body (children of the first years of life, the elderly, patients after surgical interventions or who have undergone a long course of antibiotic therapy) are at particular risk, toxic infections can be the most difficult for them. In the pathogenesis of toxic infections, the main role is played by toxins secreted by pathogens. Depending on the predominant type of toxins, the features of the clinical course also differ.
 

Treatment

The primary therapeutic measure for food poisoning is the most rapid probing and gastric lavage (in the very first hours of the onset of clinical signs of poisoning). If nausea and vomiting persist, this procedure can be carried out later. To get rid of intestinal toxins, enterosorbents are used and a siphon enema is produced. To prevent dehydration, the patient is given fractionally small portions of rehydration solutions, sweet tea. The amount of fluid taken by the patient should compensate for its loss with vomiting and feces.
With the development of a severe degree of dehydration, intravenous administration of rehydration mixtures is performed. Patients with toxicoinfection during the acute period are recommended therapeutic nutrition. In severe cases, antibiotics may be prescribed. After the cessation of vomiting and diarrhea, enzyme preparations (pancreatin, trypsin, lipase, amylase) are often recommended for the speedy restoration of digestion and probiotics or products containing bacteria necessary for the normalization of intestinal biocenosis.

Tests Required for Diagnosis

When diagnosing food poisoning, the pathogen is isolated from vomit, feces, gastric lavage. When a pathogen is detected, bacteriological culture is performed on nutrient media and its toxigenic properties are determined. However, in many cases detection is not possible. In addition, not always identified microorganisms are the direct cause of toxic infection. The relationship of the pathogen with the disease is determined either by serological tests, or by isolating it from food products and from persons who have eaten the same food as the patient.
 

Useful info

Classification of food poisoning:

I. Food poisoning of bacterial origin:

1. Food poisoning caused by various microbes (toxic infections).

2. Food intoxication: botulism, staphylococcal intoxication.

ii. Food poisoning of non-bacterial origin:

1. Food poisoning with poisonous products:

a) Food poisoning with products of animal origin;

b) Food poisoning by products of plant origin:

• Poisoning by poisonous plants;

• Poisoning with plant products that acquire toxic properties (potatoes, mycotoxicosis).

2. Food poisoning with toxic impurities:

• Poisoning with toxic impurities of chemical origin (insecticides, fungicides, inorganic compounds);
• Poisoning with toxic impurities of plant origin.

III. Food poisoning of an unknown nature.

The centers of sanitary and epidemiological surveillance take an active part in the investigation of food poisoning. Cases of fatal food poisoning, and sometimes non-fatal in some group intoxications, are subject to mandatory forensic medical examination.
Forensic medical examination of food poisoning is important not only to assist the investigating authorities in establishing the cause of death and the sources of food poisoning, but can and should play a role in the prevention of such misfortunes, as well as in identifying the facts of incorrect intravital diagnosis of food poisoning. In such cases, the forensic medical examination comes into close contact with the health authorities, and primarily with the centers of sanitary and epidemiological surveillance.