sICAM-1 intrathecal synthesis and release during the acute phase in children suffering from Coxsackie A9 and S. pneumoniae meningoencephalitis / Sintesis intratecal de sICAM-1 y liberación durante la fase aguda en niños con meningoencefalitis por Coxsackie A9 y S pneumoniae

The intercellular adhesion molecule is a transmembrane glycoprotein belonging to the immunoglobulin superfamily. Serum and cerebrospinal fluid (CSF) soluble intercellular adhesion molecule 1 (sICAM-1) from normal control children as well as from children with Guillain-Barré syndrome (GBS), with Coxsackie A9 virus meningoencephalitis and with Streptococcus pneumoniae meningoencephalitis were studied. sICAM-1 was quantified using an immunoenzimatic assay and albumin using the immunodiffusion technique in both biological fluids. Increased sICAM-1 values in CSF in patients with GBS correspond to an increase of the albumin CSF/serum quotient. In contrast, in inflammatory diseases like S. pneumoniae and Coxsackie A9 virus meningoencephalitis an increased brain-derived fraction was observed. In particular cases these values are 60-65 percent and 70-75 percent respectively. The results indicate an additional synthesis of sICAM-1 in subarachnoidal space during central nervous system (CNS) inflammatory process. An important role of sICAM-1 in the transmigration of different cell types into CSF during CNS inflammation in children with S. pneumoniae and Coxsackie A9 meningoencephalitis may be suggested.

La molécula de adhesión intercelular es una glicoproteína que pertenece a la superfamilia de las inmunoglobulinas. Se estudiaron los niveles de molécula de adhesión intercelular tipo 1 soluble (sICAM-1) en suero y líquido cefalorraquídeo (LCR) de niños con meningoencefalitis por Streptococcus pneumoniae y por Coxsackie A9 al igual que en niños con sindrome de Guillain-Barré (SGB). sICAM-1 fue cuantificado por ensayo inmunoenzimático y la albúmina por inmunodifusión en ambos líquidos biológicos. Los valores incrementados de sICAM-1 en LCR en los pacientes con GBS corresponden a valores aumentados de razón LCR/suero de albúmina. En contraste, en las enfermedades inflamatorias como las meningoencefalitis por S. pneumoniae y por Coxsackie A9 se observa un incremento en la fracción derivada del cerebro. En casos particulares los valores se incrementan hasta un 60-65 por ciento y 70-75 por ciento respectivamente. Los resultados indican una síntesis adicional de sICAM-1 en el espacio subaracnoideo durante el proceso inflamatorio del sistema nervioso central (SNC). Esto puede sugerir un importante papel del sICAM-1 en la transmigración de diferentes tipos celulares en el LCR durante la inflamación del SNC en niños con meningoencefalitis por S pneumoniae y coxsackie A9.

Diseño y evaluación de una reacción de polimerasa en cadena (RPC) múltiple, para la identificación de bacterias causantes de meningitis aguda en líquido cefalorraquídeo de niños chilenos / Multiplex PCR assay in spinal fluid to identify simultaneously bacterial pathogens associated to acute bacterial meningitis in Chilean children

Background: Acute bacterial meningitis (ABM) is a serious disease that needs rapid diagnosis for an accurate treatment. The most important etiological agents are: Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae type b. Overall pathogen detection rate in patients with ABM in Chile is 83 percent. Aim: To evaluate a Polymerase Chain Reaction (PCR) protocol for simultaneous detection of several pathogens in patients with ABM. Material and methods: We designed and evaluated a multiplex PCR protocol for simultaneous specific genes identifications of S pneumoniae (¡ytA and ply genes), N meningitidis (ctrA, crgA) and H influenzae (bexA) in cerebrospinal fluid (CSF) samples from pediatric patients with suspected diagnosis of ABM. Sensitivity, specificity and minimum detection levels of DNA were determined. Amplifications ofrDNA 16S gene was done to confirm extraction of bacterial DNA. Results: Ninety nine CSF samples were studied, 90 from children with fever and negative CSF culture, and 9 from ABM and positive culture patients. The PCR protocol had a sensitivity of 89 percent, specificity of 100 percent, positive predictive value 100 percent and negative predictive value 99 percent. Conclusions: We observed a high concordance (89 percent) between bacteriological cultures and the PCR protocol results. This diagnostic tool could increase identification of agents in specific settings such as patients previously treated with antibiotics.

Susceptibility of Streptococcus pneumoniae to penicillin in the state of Minas Gerais, Brazil from 1997-2004

We monitored the susceptibility to penicillin of invasive strains of Streptococcus pneumoniae in two reference laboratories; 502 positive cultures from patients with an active invasive infectious process were analyzed. Streptococcus pneumoniae was identified through conventional procedures, and the oxacillin disc diffusion method was used to check for penicillin susceptibility. Statistical analysis included calculations of the frequency distribution, with 95 percent confidence intervals (CI), as well as chi-square tests and chi-square for linear trend for temporal analysis of susceptibility. The bacterium was isolated from patients less than a year old (40.7 percent of the isolates), from infants (55.9 percent), and from individuals less than 15 years old (64.4 percent). The majority (88.2 percent, 95 percent CI = 85.5 percent-91.1 percent) of the 502 isolates were susceptible to penicillin. There was no significant temporal trend of elevation of resistance rate during the study period (p=0.56). We conclude that resistance of S. pneumoniae to penicillin is not yet an important clinical-epidemiological concern in the State of Minas Gerais. To provide necessary support for the adoption of therapeutic and prophylactic measures, epidemiological surveillance should be implemented at a national level to monitor the profile of susceptibility/resistance of S. pneumoniae to penicillin and other antimicrobials.