[Etiologic diagnosis in meningitis and encephalitis molecular biology techniques].
BACKGROUND
The aetiological study of infections of the central nervous system has traditionally been performed using bacterial cultures and, more recently, using polymerase chain reaction (PCR) for herpes simplex virus (HSV). Bacterial cultures may not have good performance, especially in the context of patients who have received antibiotics prior to sampling, and a request for HSV only by PCR reduces the information to only one aetiological agent. The aim of this study is to determine the infectious causes of meningitis and encephalitis, using traditional microbiology and molecular biology to improve the aetiological diagnosis of these diseases.


METHODS
A prospective study was conducted on 19 patients with suspected meningitis, admitted to the Luis Calvo Mackenna Hospital in Santiago, Chile, from March 1, 2011 to March 30, 2012. After obtaining informed consent, the CSF samples underwent cytochemical study, conventional culture, multiplex PCR for the major producing bacterial meningitis (N. meningitidis, S. pneumoniae, H. influenzae), real-time single PCR for HSV-1 and 2, VZV, EBV, CMV, HHV-6 and enterovirus. Clinical and epidemiological data were also collected from the clinical records.


RESULTS
Of the 19 patients analysed, 2 were diagnosed by conventional methods and 7 by adding molecular biology (increase to 37%). Three patients had meningitis due to S. pneumoniae, one due to Enterobacter cloacae, 2 patients meningoencephalitis HSV-1, and one VZV meningitis.


CONCLUSIONS
The addition of PCR to conventional diagnostic methods in CNS infections increases the probability of finding the causal agent. This allows a more adequate, timely and rational management of the disease.
Programa de formación en Infectología Pediátrica, Departamento de Pediatría, Campus Oriente, Facultad de Medicina, Universidad de Chile, Santiago, Chile. Electronic address: nconca@yahoo.com.
Natalia
N
Conca
Unidad de Infectología, Hospital Dr. Luis Calvo Mackenna, Providencia, Santiago, Chile.
María Elena
ME
Santolaya
Centro de Estudios Moleculares, Hospital Dr. Luis Calvo Mackenna, Providencia, Santiago, Chile.
Mauricio J
MJ
Farfan
Programa de formación en Infectología Pediátrica, Departamento de Pediatría, Campus Oriente, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
Fernanda
F
Cofré
Centro de Estudios Moleculares, Hospital Dr. Luis Calvo Mackenna, Providencia, Santiago, Chile.
Alejandra
A
Vergara
Programa de formación en Pediatría, Universidad de Chile, Santiago, Chile.
Liliana
L
Salazar
Unidad de Infectología, Hospital Dr. Luis Calvo Mackenna, Providencia, Santiago, Chile; Centro de Estudios Moleculares, Hospital Dr. Luis Calvo Mackenna, Providencia, Santiago, Chile.
Juan Pablo
JP
Torres
D002675:Child, Preschool; D002677:Chile; D004660:Encephalitis / Q000175:diagnosis* / Q000209:etiology / Q000382:microbiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008581:Meningitis / Q000175:diagnosis* / Q000209:etiology / Q000382:microbiology; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D060885:Multiplex Polymerase Chain Reaction; D011446:Prospective Studies
Diagnosis; Diagnóstico; Encefalitis; Encephalitis; Meningitis; Multiplex PCR; PCR múltiple; Polymerase chain reaction; Reacción en cadena de la polimerasa