Listeriosis: Symptoms, Diagnosis and Treatment
Listeriosis is a zoonotic infectious disease caused by bacteria of the genus Listeria and characterized by polymorphism of clinical phenomena.Cases of listeriosis are recorded on all continents.On the territory of the Russian Federation about 50-80 people a year suffer from listeriosis.In European countries, outbreaks occur periodically.So, in August 2014 in Denmark, an outbreak of listeriosis was registered, caused by the use of an infected sausage roll, as a result of which 41 people became ill.Unfortunately, seventeen people were killed.In May 2015, in the same country, a new outbreak of infection emerged, which resulted in five people falling ill and two died.Table of contents:
The causative agent of listeriosis in humans is the bacterium Listeria monocytogene.Bacteria are very stable in the environment and can persist for a long time in soil, water, food.Listeria is found everywhere, but not all people, when in contact with bacteria develop an acute form of listeriosis.The risk of the disease is susceptible to young children, the elderly, pregnant women, as well as persons with immunodeficiency conditions.Sources of infection are sick wild( rodents, hares, foxes, wild boars), agricultural( sheep, goats, pigs), domestic animals( dogs, cats), as well as birds( chickens, geese, ducks, turkeys,Parrots, canaries, parrots).An infected animal with secretions infects the environment.
How can a person get sick? The following ways of transmission of infection are distinguished:
- Alimentary - infection occurs when meat, milk, cheese, eggs are used from a sick poultry( animal), vegetables, salads, water, infected with secretions of rodents.
- Contact - in contact with an infected animal or products of their vital activity through damaged skin, mucous membranes, conjunctiva.
- Aerogenic - when inhaled by fluff, dust when processing the skins of infected animals.
- Transmissible - when bitten by ticks and fleas parasitizing on a sick animal;
- Vertical - the infection is transmitted in utero from the mother to the child.
Listeria is introduced through the mucous membranes of the tonsils, the digestive and respiratory tract, conjunctiva, damaged skin.Then the listeria is spread by the lymphogenous or hematogenous pathway.Bacteria migrate through lymphatic vessels to regional lymph nodes.Here the immune system tries to stop, localize the infection and for this, produces immune cells.Bacteria can spread to more distant lymph nodes, as well as into tonsils, spleen and liver.
If the immune system can not stop the infection, listeria is carried throughout the body with blood.Bacteria can settle in any organs, particularly in the brain.In the affected organs listeriomas are formed - sites of tissue destruction containing immune cells and listeria.
Symptoms of Listeriosis
The incubation period lasts from two to four weeks.The state of the immune system determines the course of the disease.So, many people have the disease in a latent( chronic) form.In the chronic form of listeriosis, bacteria are in the human body for a long time, but they do not cause specific clinical manifestations.Periodic exacerbations are possible by type of lung flu-like conditions or chronic pyelonephritis.
Against the background of a weak immune response, listeria of various organs is affected, sepsis develops. The following forms of listeriosis are distinguished:
- Listeriosis of pregnant women;
- Listeriosis of newborns.
This form of listeriosis occurs most frequently.The disease begins with a sudden increase in temperature, weakness, muscle pain.The patient complains of a sore throat when swallowing.At survey it is possible to visualize reddening of a pharynx, puffiness of tonsils that testifies to a catarral angina.
If the tonsils can detect grayish filmy raids, ulcers, then it is a question of ulcerative-pleous sore throat.This form of angina is more severe: the intoxication syndrome is more pronounced, the temperature reaches 39-40 degrees.There is an increase in cervical, mandibular lymph nodes.
In the absence of treatment, listeria penetrate into the blood and are carried throughout the body.This condition is called sepsis.The indicator of body temperature exceeds 40 degrees, the person is very weak, sluggish.It is noteworthy that the temperature can then go up and down.Patients are troubled by a runny nose, coughing, whitish coating on tonsils.There is an increase in different groups of lymph nodes, as well as the liver and spleen.On the skin there are single or multiple red rashes, condensation near large joints.Sometimes the leading symptoms of the disease in humans are fever, rashes, hepatosplenomegaly.In this case, they speak of a typhoid-like form of listeriosis.
This form of the disease develops if the conjunctiva of the eyes serves as an entrance gate for infection.One or both eyes can be affected.Against the background of high temperature, general weakness, eye damage develops according to the type of conjunctivitis.There is a swelling of the eyes, narrowing of the eye gap, there may be lacrimation, purulent discharge from the eye.Patients complain of redness and dry eyes.In addition, there is a deterioration in vision, patients say that they see everything through the fog.There is an increase in parotid and cervical lymph nodes.
The nervous system is affected by the penetration of Listeria monocytogene through the blood-brain barrier.It occurs in about 5-10% of patients with listeriosis, among them mostly children.The nervous form is manifested by meningeal, meningoencephalitic and encephalitic syndromes. The most common symptoms of :
- Severe headache;
- Vomiting that does not bring relief;
- Rigidity of the occipital muscles;
- Positive meningeal symptoms;
- Elevated reflexes;
- Clonic convulsions;
- Paresis and paralysis of the limbs;
- Ptosis of the eyelids;
- Violation of the act of swallowing, fluttering;
- Violation of speech;
- Impaired consciousness( delirium, hallucinations).
There are also typical signs for listeriosis: fever, enlargement of lymph nodes, liver, spleen.
Listeriosis in pregnant women
As a rule, in pregnant women, the infection proceeds secretly or with little expression. Possible signs of listeriosis in pregnant women:
- Raise body temperature to 38-39 degrees;
- Muscle aches;
- Persecution and sore throat;
- Runny nose;
That is, the symptoms of the disease are completely nonspecific and are often regarded as manifestations of ARVI.Because of this, the disease is not detected on time and, accordingly, does not treat a pregnant woman.Listeria has a harmful effect on the development of the fetus.Listeria infected mothers have miscarriages, stillbirths, the birth of children with congenital listeriosis.
Listeriosis of newborns
In newborn infants, the disease is severe and often fatal.Infants have a body temperature of 38-39 degrees, bronchopneumonia, bronchopneumonia, accompanied by dyspnoea, apnea, cyanosis, possibly purulent pleurisy.There is splenomegaly, jaundice appears already in the first day of life.Some children develop meningeal symptoms, convulsions, paralysis.On the skin of the trunk, limbs, there is an exanthematous rash.First, the rash can be characterized as spots, which are then transformed into papules and vesicles.
In 15-20% of children who have recovered, signs of central nervous system damage remain.
Diagnosis of Listeriosis
To diagnose listeriosis, one must rely on the patient's symptoms and complaints, the epidemiological history. Clinical and instrumental studies will confirm the diagnosis:
- Clinical blood test( characterized by leukocytosis, an increase in the number of monocytes, an acceleration of the ESR, a decrease in platelets);
- Analysis of cerebrospinal fluid( pressure increase, lymphocyte neutrophil or neutrophilic pleocytosis, increase in protein level);
- Bacterial seeding of the patient's biomaterial( mucus from the pharynx, blood, cerebrospinal fluid, secretion from the eyes, urine, biopsy specimens of the lymph nodes);
- PCR( detection of DNA fragments of listeria);
- Serological methods: ELISA, RA, RNGA, RSK( allows to determine specific antibodies to Listeria).
Treatment of listeriosis
Treatment of listeriosis should be performed in a hospital setting.The basis of therapy - the appointment of antibacterial agents.Ideally, an antibiotic is prescribed taking into account the result of listeria sensitivity to a particular drug.In practice, however, antibiotics are prescribed empirically, since it is not advisable to wait for colonies of bacteria to grow - it is necessary to start treatment as early as possible.
In the treatment of listeriosis, antibiotics are used from groups of penicillins, tetracyclines, macrolides, aminoglycosides, sulfonamides.Duration of admission is 14-21 days.
Given the presence of bacteremia, the patient should always carry out detoxification therapy.For this purpose, solutions of sodium chloride, glucose, sodium bicarbonate, potassium and calcium chloride are used.In the presence of cerebral edema, furosemide is prescribed.In severe listeriosis resort to the appointment of glucocorticosteroids.
Since the main pathway for the transfer of listeriosis is alimentary, the quality of the consumed products should be carefully monitored.You can eat only well-processed meat, fish, poultry, milk, eggs.It is necessary to avoid pasteurized milk, semi-finished products, sausages.Vegetables and fruits should be washed thoroughly.
You can infect listeriosis by drinking contaminated water, so you can drink only purified water.
It is necessary to clean quality cutting boards, knives.Raw meat should be stored separately from the finished products.
Listeriosis is transmitted by contact, so it is better to limit contact with wild, stray animals, birds.It is especially important to explain the danger of such contacting children.Remember that rodents are a particular danger, therefore, it is necessary to carry out deratization activities.
Individuals who work at meat processing plants, agricultural enterprises, should use personal protective equipment.
Grigorova Valeria, medical reviewer