Institute for Microbiology, Medical Faculty of Masaryk University     and St. Anna Faculty Hospital
                                              in Brno







                                     Agents of neuroinfections











                          Importance of central nervous system infections

•           CNS infections –  relatively rare,          but can have a very serious course

•           Incidence                                       bacterial meningitis: 2/100.000/year
viral meningitis:      10/100.000/year

•           Lethality                                              bacterial meningitis,
non-treated: >70 %

                                               treated: ~10 %

                                       Penetration into CNS



•           From a peripheral focus:

    by means of blood (meningococci)

    per continutitatem (pneumococci or

        haemophili from the middle ear)

    along nerves (HSV, rabies virus)



•           Directly:

    after an injury  (pneumococci, staphylococci, nocardiae, aspergilli)



                                     Etiology of CNS infections

It depends on the type and the duration of the disease, therefore it is different in



1. acute bacterial meningitis

2. acute viral meningitis

3. chronic meningitis

4. encephalitis

5. acute brain abscess

6. chronic brain abscess



                                  Etiology of acute meningitis – I

Always distinguish purulent meningitis (nearly always of bacterial origin)

      from aseptic one (usually of viral origin)

Anamnesis

Clinical disease

Laboratory – above all the examination of CSF

      cytology (appearance and number of cells)

      biochemistry (proteins and glucose)

      microbiology (microscopy, antigens, culture)

                                 Etiology of acute meningitis – II

                                 Cytology and biochemistry of CSF

                                 Etiology of acute meningitis – III

                          Etiology of purulent meningitis by the age in %



                                 Etiology of acute meningitis – IV

                          Etiology of purulent meningitis by the age in %



                                  Etiology of acute meningitis – V

                          Etiology of purulent meningitis by the age in %



                                 Etiology of acute meningitis – VI

                          Etiology of purulent meningitis by the age in %

                                 Etiology of acute meningitis – VII

                          Etiology of purulent meningitis by the age in %





                                Etiology of acute meningitis – VIII

                          Etiology of purulent meningitis by the age in %



                                 Etiology of acute meningitis – IX

                      Importance of purulent meningitis according to etiology

                                      (lethality and sequelae)

                                  Etiology of acute meningitis – X

The most common agents of aseptic meningitis:

                                              viruses

mumps virus  (but CNS infection is clinically silent)

enteroviruses: echoviruses (30 serotypes)

                          coxsackieviruses (23 + 6 serotypes)

tick-borne encephalitis virus (TBEV)

rarely HSV and VZV and other neuroviruses



                                       rarely some bacteria

leptospirae, borreliae, Mycobacterium tuberculosis

                             Overview of Central-European neuroviruses

tick-borne enceph. v. *     other arboviruses

enteroviruses: polio *       LCMV

                    coxsackie      /morbilli v./*

                    echo               /EBV/

mumps v.*                         /polyomaviruses JC & BK/

HSV, VZV *, CMV               /HIV/

rabies v. *                           /prions/





                                 Arboviruses in Central Europe – I

                                Arboviruses in Central Europe – II

Arboviruses isolated in Czech Republic, probably  nonpathogenic for humans:

            Bunyaviridae: Lednice

                                     Sedlec



Other European pathogenic arboviruses, which may be imported:

     dengue v. (flavivirus, Greece)

     CCHFV (nairovirus, Ukraine, Bulgaria)

     Toscana v. (phlebovirus, Italy)

     Bhanja v. (bunyavirus, Slovakia)

     chikungunya v. (alphavirus, Italy)









                                  Etiology of chronic meningitis



Bacteria:  Mycobacterium tuberculosis

          (meningitis basilaris)



Moulds and yeasts:

aspergilli

Cryptococcus neoformans



                                     Etiology of encephalitis

Encephalitis – only acute, of viral origin:



- tick-borne encephalitis v.

- HSV

- enteroviruses

- mumps v.





                                  Etiology of acute brain abscess



Acute brain abscesses are only of bacterial origin:



- mixed anaerobic and aerobic flora

- staphylococci (both S. aureus and coagulase negative staphylococci)

- group A and D streptococci





                                 Etiology of chronic brain abscess

Bacteria:

    Mycobacterium tuberculosis

    Nocardia asteroides



Mycotic organisms:

    Cryptococcus neoformans (yeast)



Parasites:

    Cysticercus cellulosae (tissue form of pork tapeworm Taenia solium)







                                       Homework 2 – solution
                Leonardo da Vinci (1452-1519): Fetus in the Womb (between 1510-1512)

                                            Homework 3
                           Who painted this picture and what is its name?