Brucellosis in Children

What is brucellosis in children?

Brucellosis is an infectious-allergic disease of adults and children, which can occur in acute or chronic form, manifested by prolonged fever, damage to the musculoskeletal, cardiovascular, nervous and other systems.

According to the International Classification, brucellosis in children is divided into:

– caused by Brucella abortus;
– caused by Brucella melitensis;
– caused by Brucella canis;
– caused by Brucella suis, etc.

Epidemiology. Brucellosis is a typical zoonotic infection. In nature, animals such as pigs, cows, goats, sheep, etc. are susceptible to this disease. A person can become infected when animals reproduce that are infected with brucellosis. There is also a high risk of infection when feeding on contaminated meat, milk, dairy products and other products that come from animals that have brucella in their bodies.

Especially often infected by eating contaminated milk, which was not boiled, as well as sheep cheese, because this product does not undergo heat treatment. Skin, wool and other animal products, which may be the feces of sick animals.

The main ways of infection: alimentary, contact, aerosol. Children most often become infected with brucellosis through food, using unboiled milk and other products. Contact path is characteristic of foci of sheep brucellosis. In such cases, the child picks up the infection through the skin and mucous membranes.

Aerosol can be infected by mowing animals, combing their wool and down, cleaning the territories and rooms that contain animals or raw materials obtained from them. A person cannot become infected by a sick adult or child. It is also not known whether the transmission of the infection to the infant with the mother’s milk is possible.

Both sporadic cases and epidemic outbreaks of brucellosis are recorded. In general, residents of villages, towns, farms are infected. The peak of the disease is fixed in the winter and spring months, when calving, lambing and increased lactation of animals occur.

Children of any age can get brucellosis, but in a special risk group – children of primary school age. Rarely sick babies up to 12 months due to minimizing contact with animals and breastfeeding. Susceptibility to brucellosis is not precisely established.

Causes of Brucellosis in Children

There are 6 types of pathogens brucellosis: Br. abortussuis, Br. abortus bovis, br. ovis, Br. neotomae, Br. canis, which are divided into biotypes. The morphological and cultural properties of the above listed species differ very little. Their shape is spherical, ovoid or elongated rod-shaped. The size of Brucella is 0.3-0.8 microns.

Flagella and spore pathogen has not, can form capsules. Brucella is gram-negative, forms endotoxin, stains well with aniline dyes, and is highly invasive. The pathogen can easily penetrate the damaged or intact mucous membranes in the child’s body. Brucella are located inside the cells, and multiply there, but are able to be located extracellularly.

Brucella is not so easy to kill. They die after half an hour at ambient temperature of 60 ° C, at 100 ° C (boiling) – within a few seconds. In 5-7 minutes, the pathogen dies when exposed to sunlight and ultraviolet radiation.

Sv 3-5 minutes, you can kill Brucella disinfectants, such as 3% Lysol, 2% carbolic acid, 1% bleach solution and so on. Brucella can last up to 120 days in secretions from the birth canal of aborted animals, up to 40 days in sterilized milk, up to 45 days in sheep cheese, 9-150 days in soil, longer than 5 months in frozen meat, up to 90 days in animal hair, up to 5 months in water.

Pathogenesis in Children with Brucellosis

Brucella, getting into the body of the child through the skin and mucous membranes, soon find themselves in regional lymph nodes. There they multiply, forming a depot. These processes are called the stage of regional infection. Next, the pathogen enters the bloodstream, spreading through the body, which marks the phase of bacteremia. The infection is generalized.

Brucella settle in the child’s liver, spleen, lymph nodes, bone marrow and other organs. Long-lasting reservoirs of the infection are formed there, from which, under the influence of various factors, repeated breakthroughs of Brucella can occur. This leads to repeated bacteremia, which is symptomatic of relapses and exacerbations. In this stage of the disease, marked immune changes are observed and infectious allergy of the delayed type of hypersensitivity is formed, which determines the further course of brucellosis in children.

With this disease, phenomena of generalized vasculitis with circulatory disturbance naturally occur in the form of severe hypotension, congestive plethora in the abdominal organs, etc., which explains the state of hypersensitivity to Brucella allergens.

Especially vividly, the importance of allergy in the pathogenesis of the disease begins to manifest itself at the end of the 1st month from the onset of the disease and during the formation of the chronic course of the disease. In conditions of increased sensitization, it is especially easy to re-generalize with the release of brucella from metastatic foci, which determines the chronic recurrent course of brucellosis in many patients.

Immunity. Not all patients develop sterile immunity. In children with non-sterile immunity, the causative agent of brucellosis can persist for many years in cells of the lymph and hematopoietic system. The main factor of immunity in a child is phagocytosis. In the body, agglutinins, precipitines, opsonips, and complement-binding antibodies are also detected. Immunity is formed extremely slowly. After recovery, it gradually fades away, which can lead to repeated illnesses.

In regional lymph nodes. primary changes appear. This is a focal proliferation of tissue macrophages with the formation of giant cells and their subsequent necrosis mainly in the center of the foci of inflammation.

In the subacute and especially in the chronic stage, mainly individual organs are affected.

Symptoms of Brucellosis in Children

When infected with brucellosis in children, incubation lasts 7-40 days. The average time is 2-3 weeks. For those who have been given a vaccine, the incubation period can last up to 2 months. The disease in most cases has an acute onset, marked by a rise in temperature.

Initial symptoms of brucellosis in children:

  • headache
  • increased fatigue
  • weakness
  • muscle pain
  • joint pain
  • sleep disturbance
  • loss of appetite
  • chills alternating with sweats (in some cases).

If the child starts the disease gradually, then symptoms such as weakness, malaise, mild headache, increased fatigue, loss of appetite appear. But after 5-7 days, signs of intoxication are increasing, the peak of brucellosis occurs.

The leading symptom of this disease is fever, which can be permanent, wavy, remitting, subfebrile. In most cases, children record subfebrile temperature.

An important symptom of brucellosis in children is excessive sweating. In most cases, the lymph nodes are moderately enlarged – mainly for the cervical and inguinal. In rare cases, all other groups of lymph nodes also increase.

Brucellosis is accompanied by hepatolienal syndrome. The liver and spleen, as a rule, 2-3 cm protrude from under the ribs. Palpation pain, liver and spleen are soft. Typical symptoms are arthralgia, inflammatory changes in the connective tissue of the type of cellulite and fibrositis.

With brucellosis, rarely there can be various rashes: scarlet-like, roseolous, urticaria, hemorrhagic, and so on. Pallor of baby’s skin is usually noted. In some cases, there may be the appearance of herpes and nosebleeds.

Changes in the cardiovascular system in brucellosis are characteristic only with prolonged chronic course and in severe cases. Myocarditis, pneumonia, specific bronchitis, meningoencephalitis, meningitis, plexitis, radiculitis, orchitis, neuritis of the auditory and optic nerves, thyrotoxicosis, endometritis, endocarditis, hypothyroidism, liver cirrhosis, vasculitis, pancreatitis and other diseases may develop.

The blood test shows reticulocytosis, ESR above normal, a pronounced tendency to thromocytopenia, eosinopenia, leukopenia, monocytopenia, lymphocytosis.

Brucellosis is acute and chronic. There are such forms of the disease: mild, moderate, severe. Forms can be either clinically pronounced or erased or asymptomatic. In infants often the disease is acute. In adults and in children from 7 to 16 years, brucellosis is often chronic. In children with brucellosis, the prognosis is favorable (recovery).

Diagnosis of Brucellosis in Children

For the diagnosis of brucellosis in children use clinical, epidemiological and laboratory data. Confirmation of the diagnosis requires isolation of the causative agent of brucellosis from a sick child. To do this, I sow biological material: blood, sputum, urine, joint fluid, pus, and so on. To the selected media. Also using PCR detect Brucella antigen.

Also of importance is the serological diagnosis: Wright’s agglutination reaction with a killed brucella culture (like the Widal reaction), RSK, RPGA, etc.

Rapid diagnosis of brucellosis in a child is performed using the headdlsson agglutination reaction. The reaction is placed on a slide with different dilutions of the investigated serum. As an antigen, a killed brucella culture tinted with methylene blue is used. They can also apply the immunofluorescence method as a method of accelerated diagnosis for suspected brucellosis in children.

Treatment of Brucellosis in Children

In the acute period, the treatment is carried out with antibiotics. Most often it is chloramphenicol, erythromycin, tetracycline, rifampicin in doses dependent on age. The course is from 7 to 10 days. Often, the course is repeated after 2 weeks, in rare cases, and conduct a third course.

Antibiotics have a pronounced antimicrobial effect, but do not guarantee the absence of exacerbations, relapses and the formation of a chronic process. Vaccine therapy is given along with antibiotics (from 8 to 10 injections).

Treatment of severe acute brucellosis, as well as chronic, is carried out with glucocorticosteroids. In frequent cases, it is a prednisone course of 3 to 4 weeks. Active chronic brucellosis in children requires complex treatment with the use of interferon inductors, which allows to reduce the frequency of exacerbations and speed up remission. Also, with the active chronic form of the disease, cycloferon is administered intramuscularly, the course consists of 10 injections.

The courses of hormone therapy for chronic brucellosis in a child are repeated 2-3 times, maintaining a break of 3-4 weeks.

Also used symptomatic treatment with these drugs: analgin, amidopyrin, reopyrin, delagil. Physiotherapy is shown: UHF, ozokerite, massage, phototherapy, mud therapy, gymnastics, etc. In some cases, polyoxidonium is administered intravenously or intramuscularly (for children from 12 years of age – rectally). In chronic brucellosis, sanatorium treatment is indicated.

Prevention of Brucellosis in Children

  1. Eliminate the sources of infection among domestic animals by identifying sick individuals, conducting preventive vaccination of cattle, improving livestock farms and so on.
  2. Prevention of food infections. Food before consumption is subjected to thorough heat treatment. Milk and cream should be pasteurized for half an hour at a temperature of 70 ˚C, meat should be cooked for 3 hours, and cheese and cheese should be kept for more than 2 months.
  3. Specific prophylaxis is carried out by live avirulent brucella vaccine. Vaccination is given to children from 7 years of age according to epidemiological indications.
  4. In epidemic outbreaks, persons working with farm animals, processing products derived from animals, and children of older children who help adults in caring for animals or in processing livestock products are subject to vaccination.
  5. In epidemic outbreaks, persons working with farm animals, processing products derived from animals, and children of older children who help adults in caring for animals or in processing livestock products are subject to vaccination.
  6. Water sources should be protected from pollution, use overalls for the care of animals, use disinfectants, carry out sanitary and educational work.