Rosete SEM, Mejía DL, Morayta RA, Gómez ACM, Gómez GF

Language: Spanish
References: 13
Page: 43-51
PDF size: 94.31 Kb.

ABSTRACT

Infection of the cerebral parenchyma of viral etiology is known as viral encephalitis. It has a high degree of morbidity and mortality and produces long term sequels. It appears mostly during the first ten years of life. No epidemiological pattern has been identified due to the existence of different etiological agents that cannot be specifically isolated. Although 85–90% of cases are caused by enterovirus, they can also be due to viruses of the herpes, parotiditis and measles group. Individuals with low immunity are at greater risk of acquiring this condition, although most cases are found in immunocompetent patients.
The infection occurs after a viremia, after a direct inoculation of the virus, or after contact with free nerve endings in specialized sites. The common clinical picture in most encephalitis cases includes high temperature, headache, alterations in the level of consciousness, confusion, disorientation, conduct and language disorders. Neurological signs can be either focal or diffused and may include partial or generalized convulsive crises. The etiology may be suggested by the cellular tropism characteristic of each virus.
Diagnosis requires determining a possible exposure to an index case, a history of mosquito bites or of having been bitten by an animal. Examination of cerebrospinal fluid (CSF) is essential in confirming diagnoses, as are throat, urine, and fæcal cultures in search of adenovirus and enterovirus. Determination of results in CSF and serum requires testing in pairs. Other important tests are Polymerase Chain Reaction (PCR) and the test of Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR).
The treatment of viral encephalitis is geared towards support measures: analgesics, febrifuges, maintaining an appropriate hydroelectrolitic balance, nutritional support, control of convulsive crises, monitoring intracranial pressure. Few viral pathogens can be specifically treated. In cases of HSV Aciclovir is indicated and in those of CMV Ganciclovir is provided. Vaccine application can serve as a prophylactic measure, but there are no vaccines for all viral pathogens that potentially can cause infection. At present, vaccination is available for polio, measles, mumps, rubella, chicken pox, rabies and influenza A and B.

REFERENCES

1. Bonthius DJ, Karacay B. Meningitis and encephalitis in children. An update. Neurol Clin N Am 2002;20:1013-38.

2. Bonthius D, Karacay B. Meningitis and encephalitis in children. Neurol Clin 2000;20.

3. Roos L. Central Nervous System infections. Neurol Clin 1999; 17: 813-833.

4. Viral infections of the Nervous System, 2002. Editorial. Arch Neurol 2002; 59: 712-717.

5. Coria J, Escobar M, Velazco V. Meningoencefalitis viral . Enfoque clínico. Rev Mex Ped 2001;68:252-9.

6. Tyler KL. Herpes Simplex Virus Infections of the Central Nervous System: Encephalitis and Meningitis, Including Mollaret´s. Herpes 2004;11:57A-64A.

7. Stalkup JR, Chilukuri S. Enterovirus infections: A review of clinical presentation, diagnosis, and treatment. Dermatol Clin 2002;20: 217-23.

8. Chaudhuri A, Kennedy PG. Diagnosis and treatment of viral encephalitis. Postgrad Med J 2002;78:575-583.

9. HSV PCR for CNS infections: perils and pitfalls. Ped Infect Dis J 1999; 18: 823-824.

10. Seehusen D, Reeves M, Fomin D, Cerebrospinal Fluid Analysis. Am Fam Phis 2003; 68.

11. Thomson R, Bertram H. Laboratory diagnosis of central nervous system infections. Infect Dis Clin 2001; 15:63-88.

12. Kimberlin D. Herpes Simplex Virus, Meningitis and Encephalitis in Neonates. Herpes 2004;11:65A-76A.

13. Giraldo M. Enfermedades Inducidas por priones. Rev Hosp. Nac. 1997 jun (Citado 2004 Nov 10) (5p). Disponible en: www.google.com/ Infectologia/enfermedad por priones/html