Clinical manifestations of meningococcemia
The generalized form of the infection (meningococcemia) is characterized by an acute onset. Patients experience marked intoxication: fever (often up to 39–40°C), chills, general weakness, myalgia (especially pain in the extremities and lower back), and intense headache.
A key diagnostic sign is hemorrhagic rash. It may have a stellate or irregular shape, localized predominantly on the trunk and extremities. An important feature: the rash elements do not fade upon pressure. In severe cases, the rash rapidly coalesces, forming multiple areas of necrosis. Additionally, hemorrhages in the sclerae, facial hyperemia, and petechial enanthema on the oropharyngeal mucosa are noted.
Nervous system involvement and meningeal syndrome
The development of meningitis is accompanied by the appearance of specific neurological symptoms. Against the background of high fever and severe headache, vomiting (often without preceding nausea) and depressed consciousness occur.
Objective examination reveals meningeal signs:
- Nuchal rigidity;
- Positive Brudzinski's sign (e.g., upper);
- Kernig's sign (may be equivocal in early stages or in elderly patients).
Hyperesthesia—increased sensitivity to light, sounds, and touch—is also possible.
Laboratory diagnostics
To confirm the diagnosis, analysis of cerebrospinal fluid (CSF) obtained via lumbar puncture is of key importance.
In purulent meningitis, the CSF becomes turbid (milky in color). The analysis shows high neutrophilic pleocytosis (neutrophils covering all visual fields), elevated protein levels (e.g., up to 6 g/L), and a positive Pandy test. CSF bacterioscopy reveals gram-negative cocci. A complete blood count reveals marked leukocytosis with a left shift and an elevated ESR.
Pre-hospital stage errors
Diagnosing meningococcal infection at the outpatient stage often causes difficulties. Physicians may mistakenly mistake the hemorrhagic rash for an allergic reaction, toxico-allergic dermatitis, or manifestations of rubella.
The sudden onset of neurological symptoms (especially in elderly people) is sometimes incorrectly interpreted as acute cerebrovascular accident (cerebral hemorrhage). Incorrect assessment of the severity of the condition and the prescription of inadequate treatment (e.g., only antihistamines and antipyretics) lead to rapid decompensation, development of shock, and emergency admission to the intensive care unit.
Briefly: answers to topical questions
What vaccines are used for routine specific prevention of meningococcal infection?
For active specific prevention, polysaccharide vaccines and outer membrane protein vaccines are used. The following preparations are used:
- Polysaccharide bivalent vaccines — protect against serogroups A and C (group A monovaccines also exist).
- Polysaccharide trivalent vaccines — used against serogroups A, C, and W.
- Polysaccharide tetravalent vaccines — directed against serogroups A, C, Y, and W135 (e.g., Mencevax ACWY).
- Group B vaccines — created on the basis of the microorganism's outer membrane protein, since polysaccharide vaccines are not feasible due to antigenic mimicry.
What drugs are used for emergency chemoprophylaxis of contacts in an infection focus?
For chemoprophylaxis of contacts in the focus within the first 24 hours after registering a case of the disease, one of the following drugs is prescribed:
- Rifampicin orally: adults — 600 mg every 12 hours for 2 days; children from 12 months — 10 mg/kg every 12 hours for 2 days; children under 1 year — 5 mg/kg every 12 hours for 2 days.
- Ampicillin orally: adults — 0.5 mg/kg 4 times a day for 4 days according to the source text.
For antibacterial eradication in identified carriers at the source, ampicillin, erythromycin, or chloramphenicol in age-appropriate dosages are also indicated.
What is the duration of the incubation period for meningococcal infection?
The incubation period for meningococcal infection ranges from 1 to 10 days, usually 4–6 days. This range is taken into account when collecting the epidemiological history. For contacts in the focus, sources indicate medical observation for 10 days.
Class and exam questions
How to distinguish the rash in meningococcemia from an allergic one?
In meningococcemia, the rash is hemorrhagic in nature: it does not disappear or blanch upon pressure, often has a stellate shape, and is prone to necrosis.
What CSF changes are characteristic of meningococcal meningitis?
The CSF is turbid, milky in color. High neutrophilic pleocytosis, elevated protein content, sharply positive Pandy test, and the presence of gram-negative cocci are characteristic.
What symptoms indicate meningeal syndrome?
The main signs are nuchal rigidity, Kernig's and Brudzinski's signs, as well as intense headache, vomiting, and hyperesthesia.
What else to study on this topic
- Differential diagnosis of meningococcemia and toxico-allergic reactions
- Differential diagnosis of purulent meningitis and subarachnoid hemorrhage
- Symptom complex of typhoid status and encephalopathy in elderly patients
- Assessment of severity and prognosis in fulminant forms of infection
Master the complete topic in the «Infectious Diseases» course
This is a summary. The course covers everything tested in classes and exams.
- Complete study guide on "Prevention of Meningococcal Infection" and 3,312 more pages of the subject
- Assignments and quizzes after every topic — just like in a colloquium
- AI tutor answers questions on the topic anytime
- 41 video lessons on the subject
Other topics in the "Respiratory Infections" section
Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.