RESUMEN
Poor prognosis in Pneumococcal meningitis may be associated with high pneumolysin levels in cerebrospinal fluid (CSF). In patient samples we showed that pneumolysin levels in CSF remained high after 48 hours in nonsurvivors of meningitis compared with survivors. Selective antipneumolysin treatment may present a novel therapeutic option.
Asunto(s)
Meningitis Neumocócica/líquido cefalorraquídeo , Meningitis Neumocócica/mortalidad , Estreptolisinas/líquido cefalorraquídeo , Carga Bacteriana , Proteínas Bacterianas/líquido cefalorraquídeo , Líquido Cefalorraquídeo/microbiología , Humanos , Neuraminidasa/líquido cefalorraquídeoRESUMEN
The surveillance of serotypes causing invasive pneumococcal disease (IPD) provides further insight into the pathogenesis of pneumococcal disease and is important in order to track vaccine impact. Although the Quellung reaction has been accepted as the standard method for serotyping, prior antibiotic use causes a gap in studies based on bacterial culture. A total of 31 cerebrospinal fluid (CSF) samples found to be positive for Streptococcus pneumoniae by polymerase chain reaction (PCR) targeting the ply gene during an active surveillance were tested in a Bio-Plex multiplex antigen detection assay capable of detecting 14 serotypes/groups (1, 3, 4, 5, 6A, 6B, 7F/A, 8, 9V, 14, 18, 19A, 19F, and 23F). Twenty-seven CSF samples could be serotyped. The most common serotypes were serotypes 5 (n = 7), 19F (n = 5), 1 (n = 3), and 23F (n = 3). Theoretical coverage rates by the heptavalent (PCV7), 10-valent (PCV10), and 13-valent (PCV13) pneumococcal conjugate vaccines for bacterial meningitis were 48.1, 85.2, and 92.3%, respectively, for all age groups and 71.4, 85.7, and 100.0%, respectively, for those under 2 years of age. We propose that antigen detection assay used in conjunction with a PCR assay can be effectively applied in CSF samples to detect the pneumococcal serotypes, especially when the patient may have already been treated and, therefore, the cultures would be negative.
Asunto(s)
Meningitis Neumocócica/microbiología , Reacción en Cadena de la Polimerasa/métodos , Serotipificación/métodos , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/genética , Antígenos Bacterianos/líquido cefalorraquídeo , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/líquido cefalorraquídeo , Proteínas Bacterianas/genética , Preescolar , Estudios de Cohortes , ADN Bacteriano/líquido cefalorraquídeo , Reacciones Falso Negativas , Humanos , Lactante , Meningitis Neumocócica/epidemiología , Vigilancia de la Población , Vacunas Estreptocócicas/inmunología , Streptococcus pneumoniae/aislamiento & purificación , Estreptolisinas/líquido cefalorraquídeo , Estreptolisinas/genética , Turquía/epidemiologíaRESUMEN
BACKGROUND & OBJECTIVES: Pneumolysin, a toxin produced by Streptococcus pneumoniae is associated with virulence and is found in all invasive isolates. Its role as a diagnostic tool has recently been exploited. Most of the methods used are based on molecular techniques and are not cost-effective. The present study was undertaken to evaluate a simple, rapid and cost-effective method to detect pneumolysin in CSF as a diagnostic test for pneumococcal meningitis. METHODS: A total of 75 CSF samples from children with presumptive diagnosis of acute pyogenic meningitis or encephalitis were subjected to Gram stain, culture and pneumolysin detection by Cowan 1 staphylococcal protein A co-agglutination technique. RESULTS: Pneumolysin was detected in 26(78.8%) of 33 culture proven CSF samples and 4(9.5%) of 42 culture negative samples. Antigen detection by Co-A had a specificity of 90 per cent and a sensitivity of 79 per cent when compared with culture. Compared to Gram stain, pneumolysin Co-A had a specificity and sensitivity of 91.0 and 92.0 per cent respectively. INTERPRETATION & CONCLUSION: Detection of pneumolysin was found to be a simple, low cost antigen detection assay for rapid diagnosis of pneumococcal meningitis, for routine use in the developing countries.
Asunto(s)
Meningitis Neumocócica/diagnóstico , Estreptolisinas/líquido cefalorraquídeo , Pruebas de Aglutinación/métodos , Proteínas Bacterianas , Niño , Preescolar , Humanos , Lactante , Sensibilidad y Especificidad , Proteína Estafilocócica ARESUMEN
Pneumolysin, a virulence factor of Streptococcus pneumoniae with cytotoxic and proinflammatory activities, occurs at concentrations from 0.85 to 180 ng/ml in cerebrospinal fluid (CSF) of meningitis patients. In pneumococcal cultures and in a rabbit meningitis model, the concentrations of pneumolysin in supernatant and CSF were lower after addition of nonbacteriolytic bactericidal antibiotics (rifampin and clindamycin) than after incubation with ceftriaxone.