Meningococcal infection

Meningococcal infection is an acute anthroponous infectious disease with an aerosol mechanism of transmission of the pathogen, which is characterized by fever, intoxication, hemorrhagic rash and purulent inflammation of the brain membranes.

ICD-10 codes

• A39. Meningococcal infection.
• A39.1. Waterhouse-Frideriksen syndrome, meningococcal adrenalitis, meningococcal adrenal syndrome.
• A39.2. Acute meningococcemia.
• A39.3. Chronic meningococcemia.
• A39.4. Meningococcemia, unspecified.
• A39.5. Meningococcal disease of the heart. Meningococcal: cardiovascular system; endocarditis; myocarditis; pericarditis.
• A39.8. Other meningococcal infections. Meningococcal: arthritis; conjunctivitis; encephalitis; neuritis of the retrobulbar. Post-meningococcal arthritis.
• A39.9. Meningococcal infection, unspecified. Meningococcal disease of the BDU.

What causes meningococcal infection?

Meningococcal infection is caused by meningococcus (Neisseria meningitidis), which causes meningitis and septicemia. Symptoms of meningococcal infection, usually acute, include headache, nausea, vomiting, photophobia, drowsiness, rash, multiple organ failure, shock and ICE. Diagnosis is based on clinical manifestations of infection and is confirmed by culture research. Treatment of meningococcal infection is carried out by penicillin or cephalosporins of the 3rd generation.

Meningitis and septicemia account for more than 90% of meningococcal infections. Infectious lesions of the lungs, joints, respiratory tract, urogenital organs, eyes, endocardium and pericardium are less common.

The frequency of endemic morbidity in the world is 0.5-5 / 100 000 population. The incidence increases in winter and spring in temperate climates. Local outbreaks of infection most often occur in the region of Africa between Senegal and Ethiopia. This region is called the zone of meningitis. Here the incidence rate is 100-800 / 100 000 population.

Meningococci can inhabit the oropharynx and nasopharynx of asymptomatic carriers. Most likely, the carrier becomes a patient under the influence of a combination of factors. Despite the reported high carrier frequency, the transition of carrier to invasive disease occurs rarely. This is more common in people who have not previously been infected. Usually transmission of infection occurs by direct contact with respiratory secretions of the carrier. The carrier frequency increases significantly during epidemics.

After entering the body, meningococcus causes meningitis and acute bacteremia in both children and adults, which leads to diffuse vascular effects. This infection can quickly take fulminant course. It is associated with a mortality rate of 10-15% of cases. In 10-15% of the recovered patients, serious consequences of the transferred infection develop, such as permanent hearing loss, slowing down of thought processes or loss of phalanges or limbs.

The most common infections are children aged 6 months to 3 years. Also at risk are adolescents, conscripts, students who recently live in the hostel, people with defects in the complement system and microbiologists working with meningococcal isolates. Infection or vaccination leave behind a type-specific immunity.

How is meningococcal disease diagnosed?

Meningococci are small, gram-negative cocci, which are easily detected by Gram staining and other standard bacteriological identification methods. Meningococcal infection is diagnosed using serological methods, such as latex agglutination and coagulation tests, which can quickly put a preliminary diagnosis of meningococcus in the blood, cerebrospinal fluid, synovial fluid and urine.

Both positive and negative results should have cultural confirmation. PCR can also be used to detect meningococcus, but this is economically unreasonable.

How is meningococcal infection treated?

Until reliable results are obtained for the detection of causative MI, an immunocompetent adult suspected of having a meningococcal infection is prescribed a third generation cephalosporin (eg cefotaxime 2 g intravenously every 6 hours or ceftriaxone 2 g intravenously every 12 hours plus vancomycin 500 mg intravenously every 6 or 1 g intravenously every 12 hours). In immunocompromised people, Listeria Monocytogenes should be treated, for this, 2 g of ampicillin intravenously every 4 hours is added to the treatment. With the reliable establishment of meningococcus as a causative agent, the drug of choice is penicillin 4 million units intravenously every 4 hours.

The appointment of glucocorticoids reduces the incidence of neurological complications in children. In the event that antibiotics are prescribed, the first dose should be given together or before the first dose of antibiotics. Meningococcal infection in children is treated with dexamethasone at a dose of 0.15 mg / kg intravenously every 6 hours (10 mg every 6 hours for adults) for 4 days.

How is meningococcal infection prevented?

Persons who were in close contact with a patient with meningococcal disease have a high risk for developing the infection, so they should receive preventive treatment for meningococcal infection with an antibiotic. The drugs of choice for them are rifampin 600 mg orally every 12 hours, total 4 doses (for children over 1 month 10 mg / kg orally every 12 hours, only 4 doses, for children younger than 1 month 5 mg / kg orally every 12 hours hours, only 4 doses) or ceftriaxone 250 mg intramuscularly 1 dose (for children younger than 15 years 125 mg intramuscularly 1 dose) or a single dose of fluoroquinolone for adults (ciprofloxacin or levofloxacin 500 mg or ofloxacin 400 mg).

In the US, a meningococcal conjugate vaccine is used. The vaccine from meningococcal infection contains 4 out of 5 serogroups of meningococci (all except group B). People who are at high risk of developing meningococcal infections should be vaccinated. The vaccine is recommended to draftees traveling in endemic regions, people with laboratory or industrial exposure with aerosols containing meningococcus, and patients with functional or actual asplenia. The possibility of vaccination should be considered for admission to universities, especially for those who will live in a hostel, for people who have been in contact with patients, for medical and laboratory personnel and for patients with immunodeficiency.

Generalized meningococcal infection is an occasion for hospitalization. Identified in the environment of the patient carriers are isolated and sanitized. According to epidemiological indications, vaccines are introduced for the prevention of meningococcal infections:

• vaccine meningococcal group A polysaccharide dry at a dose of 0.25 ml - for children from 1 to 8 years and 0.5 ml - for children 9 years, adolescents and adults (subcutaneously once);
• polysaccharide meningococcal vaccine group A and C in a dose of 0.5 ml - for children from 18 months (according to the indications - from 3 months) and adults subcutaneously (or intramuscularly) once;
• mentseks ACWY in a dose of 0.5 ml - for children from 2 years and adults subcutaneously once.

What are the symptoms of meningococcal infection?

Patients with meningitis often indicate fever, headache and stiffness in the neck. Other symptoms of meningococcal infection include nausea, vomiting, photophobia and lethargy. Maculopapular and hemorrhagic rash often appears after the onset of the disease. Meningeal signs are often detected in a physical examination. Syndromes with fulminant meningococcemia are as follows: Waterhouse-Friderecksen syndrome (septicemia, developed shock, dermal purpura and hemorrhage in the adrenal cortex), sepsis with multiple organ failure, shock and ICE. Rarely chronic meningococcemia causes recurrent mild symptoms.

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