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Pneumococcal Meningitis (pneumococcal + meningitis)
Kinds of Pneumococcal Meningitis Selected AbstractsMorphological Correlates of Acute and Permanent Hearing Loss During Experimental Pneumococcal MeningitisBRAIN PATHOLOGY, Issue 2 2003Matthias Klein In patients with acute bacterial meningitis, hearing loss can be transient but is often permanent. The mechanisms underlying meningitis-associated hearing loss are not fully understood. Therefore, we investigated the morphological correlates of hearing loss in a rat model of pneumococcal meningitis. Transcutaneous intracisternal injection of Streptococcus pneumoniae resulted in a dose-dependent hearing loss (determined by auditory brainstem response audiometry), which was partially reversible during the acute stage. Nevertheless, a severe permanent hearing loss persisted until 2 weeks after infection. Suppurative labyrinthitis was accompanied by blood-labyrinth barrier disruption (determined by cochlear Evans blue extravasation), which correlated closely with hearing loss during the acute stage but not after recovery. Two weeks after infection, spiral ganglion neuronal density was markedly decreased and correlated with the severity of permanent hearing loss. Neuronal loss can be explained by the new finding of meningitis-associated spiral ganglion neuronal necrosis rather than apop-tosis (determined by morphology, TUNEL staining, and immunohistochemistry). [source] Transcriptional Regulation of Caspases in Experimental Pneumococcal MeningitisBRAIN PATHOLOGY, Issue 3 2001Matthias von Mering Apoptosis and necrosis in brain account for neurological sequelae in survivors of bacterial meningitis. In meningitis, several mechanisms may trigger death pathways leading to activation of transcription factors regulating caspases mRNA synthesis. Therefore, we used a multiprobe RNA protection assay (RPA) to examine the expression of 9 caspase-mRNA in the course of experimental Streptococcus pneumoniae meningitis in mouse brain. Caspase-6, -7 and -11 mRNA were elevated 6 hours after infection. 12 hours after infection caspases-1, -2, -8 and -12 mRNA rose. Caspase-14 mRNA was elevated 18 h and caspase-3 mRNA 24 h after infection. In situ hybridization detected caspases-3, -8, -11 and -12 mRNA in neurons of the hippocampal formation and neocortex. Development of sepsis was paralleled by increased transcription of caspases mRNA in the spleen. In TNF,-deficient mice all caspases examined were less upregulated, in TNF-receptor 1/2 knockout mice caspases-1, -2, -7, -11 and -14 mRNA were increased compared to infected control animals. In caspase-1 deficient mice, caspases-11, and -12 mRNA levels did not rise in meningitis indicating the necessity of caspase-1 activating these caspases. Hippocampal formations of newborn mice incubated with heat-inactivated S. pneumoniae R6 showed upregulation of caspase-1, -3, -11 and -12 mRNA. These observations suggest a tightly regulated caspases network at the transcriptional level in addition to the known cascade at the protein level. [source] Epidemiology of invasive pneumococcal infections in children aged 0,6 years in Denmark: a 19-year nationwide surveillance studyACTA PAEDIATRICA, Issue 2000MS Kaltoft The impact of the new pneumococcal conjugate vaccines on invasive disease burden in Danish children was evaluated by analysing the results from the last 19 years of a nationwide surveillance of invasive pneumococcal infections. During 1981,1999, the Streptococcus Unit at Statens Serum Institut, Copenhagen, received 1123 invasive pneumococcal isolates from children aged 0,6 years. Nearly 72% (71.8%) of the pneumococcal isolates were from children aged <2 y. The median ages of children with pneumococcal meningitis and bacteraemia were 10.2 mo and 15.9 mo, respectively. The incidence of pneumococcal meningitis remained stable during the study period. The mean annual incidence rates of pneumococcal meningitis among children aged <1, <2, and <7 years were 17.4, 12.4, and 4.3 per 100000, respectively, during 1981,1999 (overlapping age groups are used throughout this article to facilitate the comparison of incidence data from different countries or among different studies). The annual incidence of pneumococcal bacteraemia increased from 1981 to 1996, after which a slight fall was noted. During the last six years of the study period, the mean annual incidence rates of bacteraemia were 30.1, 32.5, and 14.0 per 100000 children aged <1, <2, and <7 years. In the 1990s, pneumococcal isolates with reduced sensitivity to penicillin (0,5% each year) and erythromycin (7.4% in 1999) emerged as a cause of invasive infections in children aged 0,6 years in Denmark. During 1981,1999, 10 serotypes (1, 4, 6A, 6B, 7F, 9V, 14, 18C, 19F, 23F) caused 82% of invasive infections in Danish children. Importantly, no significant temporal changes in overall serotype distribution or differences in serotype distributions between girls and boys could be documented during the study period. Conclusion: According to the Kaiser Permanente trial, the 7-, 9-, and 11-valent pneumococcal conjugate vaccines will probably cover around 60%, 70%, and 80%, respectively, of all invasive pneumococcal infections in Danish children aged 0,6 y, corresponding to 12,14 episodes of meningitis and 40,60 episodes of bacteraemia per year. [source] Epidemiology of invasive and other pneumococcal disease in children in England and Wales 1996,1998ACTA PAEDIATRICA, Issue 2000E Miller The results of enhanced national surveillance of pneumococcal disease in children <15y of age in England and Wales are reported for the period 1996,1998. Of the 1985 cases of laboratory-confirmed invasive disease (annual incidence 6.6 per 100000 overall and 39.7 per 100000 in infants <1 y of age), 485 (24%) were meningitis (annual incidence of 1.6 per 100000 overall and 15.7 per 100000 in infants <1 y of age). Fifty-nine deaths in children with invasive disease were identified-3% of the total reports. Thirty-one different serogroups/types were identified, with organisms in the 7-valent conjugate vaccine responsible for 69% of the infections in children <5 y of age; this rose to 77% and 82%, respectively, for the 9-and 11-valent vaccines. Resistance to penicillin varied from 2.3% to 6.2% in different years, but erythromycin resistance remained constant at 17%. The vast majority of resistant isolates were in vaccine serotype/groups. Computerized hospital admission records for all children <15 y of age with a discharge diagnosis code indicating probable pneumococcal disease were also analysed for 1997. The annual incidence for cases with a code specifically mentioning S. pneumoniae was 9.9 per 100000 compared with 71.2 per 100000 for lobar pneumonia; the mean duration of stay for both was < 1 wk. The incidence of admission for pneumococcal meningitis (1.9 overall and 19.6 for infants < 1 y of age) was similar to that derived from laboratory reports and resulted in an average duration of stay of 2 wk. Conclusion: This surveillance has confirmed the substantial burden of morbidity attributable to pneumococcal disease in British children and the potential public health benefits that could be achieved by the use of pneumococcal conjugate vaccines. [source] Systemic steroid reduces long-term hearing loss in experimental pneumococcal meningitis,THE LARYNGOSCOPE, Issue 9 2010Lise Worsøe MD Abstract Objectives/Hypothesis: Sensorineural hearing loss is a common complication of pneumococcal meningitis. Treatment with corticosteroids reduces inflammatory response and may thereby reduce hearing loss. However, both experimental studies and clinical trials investigating the effect of corticosteroids on hearing loss have generated conflicting results. The objective of the present study was to determine whether systemic steroid treatment had an effect on hearing loss and cochlear damage in a rat model of pneumococcal meningitis. Study Design: Controlled animal study of acute bacterial meningitis. Methods: Adult rats were randomly assigned to two experimental treatment groups: a group treated with systemic steroid (n = 13) and a control group treated with saline (n = 13). Treatment was initiated 21 hours after infection and repeated once a day for three days. Hearing loss and cochlear damage were assessed by distortion product otoacoustic emissions (DPOAE), auditory brainstem response (ABR) at 16 kHz, and spiral ganglion neuron density. Results: Fifty-six days after infection, steroid treatment significantly reduced hearing loss assessed by DPOAE (P < .05; Mann-Whitney) and showed a trend toward reducing loss of viable neurons in the spiral ganglion (P = .0513; Mann-Whitney). After pooling data from day 22 with data from day 56, we found that systemic steroid treatment significantly reduced loss of spiral ganglion neurons (P = .0098; Mann-Whitney test). Conclusions: Systemic steroid treatment reduces long-term hearing loss and loss of spiral ganglion neurons in experimental pneumococcal meningitis in adult rats. The findings support a beneficial role of anti-inflammatory agents in reducing hearing loss and cochlear damage in meningitis. Laryngoscope, 2010 [source] Cochlear Preservation After Meningitis: An Animal Model Confirmation of Adjunctive Steroid Therapy,THE LARYNGOSCOPE, Issue 2 2006John Addison MA Abstract Objective/Hypothesis: The objective of the present study was to determine whether treating pneumococcal meningitis with a combined antibiotic and steroid regime will prevent cochlear damage, a common pneumococcal meningitis side effect. Study Design: This was a prospective animal study. Methods: Gerbils were randomly assigned to three experimental groups. Animals in group 1, the control animals, received intrathecal saline injections. Animals in groups 2 and 3 received intrathecal injections of Streptococcus pneumoniae to induce meningitis. Although group 2 solely was treated for 7 days with intraperitoneal penicillin injections (48,0000 units), group 3 received, in addition to the antibiotic for 4 days, 0.5 mg/kg intraperitoneal dexamethasone injections. Three months after the meningitis was induced, the animals' cochlear function was determined using auditory brainstem responses (ABRs). Fifteen frequencies were tested, five octaves at three steps per octave between 2 and 50 kHz. Results: ABR thresholds were significantly elevated only in group 2. When compared with group 1, ABR thresholds were 19 dB higher (P < .05). Frequencies at the low-frequency end of the hearing range were affected more than the midfrequencies. Animals that received dexamethasone had 2-dB higher thresholds than the control group (P > .05). Conclusions: Dexamethasone therapy in conjunction with antibiotic therapy preserves cochlear function in cases of S. pneumoniae meningitis in the Mongolian gerbil model. [source] Morphological Correlates of Acute and Permanent Hearing Loss During Experimental Pneumococcal MeningitisBRAIN PATHOLOGY, Issue 2 2003Matthias Klein In patients with acute bacterial meningitis, hearing loss can be transient but is often permanent. The mechanisms underlying meningitis-associated hearing loss are not fully understood. Therefore, we investigated the morphological correlates of hearing loss in a rat model of pneumococcal meningitis. Transcutaneous intracisternal injection of Streptococcus pneumoniae resulted in a dose-dependent hearing loss (determined by auditory brainstem response audiometry), which was partially reversible during the acute stage. Nevertheless, a severe permanent hearing loss persisted until 2 weeks after infection. Suppurative labyrinthitis was accompanied by blood-labyrinth barrier disruption (determined by cochlear Evans blue extravasation), which correlated closely with hearing loss during the acute stage but not after recovery. Two weeks after infection, spiral ganglion neuronal density was markedly decreased and correlated with the severity of permanent hearing loss. Neuronal loss can be explained by the new finding of meningitis-associated spiral ganglion neuronal necrosis rather than apop-tosis (determined by morphology, TUNEL staining, and immunohistochemistry). [source] Health related quality of life in survivors of pneumococcal meningitisACTA PAEDIATRICA, Issue 3 2009Rosa Legood Abstract Aim: To estimate the overall long-term health related quality of life implications of an episode of pneumococcal meningitis in childhood. Method: Cases were identified through two regional UK surveillance studies and traced via their general practitioners (GPs) or local hospital paediatrician. Siblings were used as controls where available. Health related quality of life was assessed using the health utilities index (HUI). Mean utility scores were compared between cases and controls and univariate linear regression was used to identify factors that influenced the overall utility scores. Results: HUI data were available for 71 cases and 66 controls. The mean overall utility score for cases 0.774 (95% CI 0.711, 0.837) was significantly lower than for controls 0.866 (95% CI 0.824,0.907) (p-value = 0.0185). Hearing was the most significantly affected health attribute (p-value < 0.006). In cases, males had lower quality of life scores than females (p-value = 0.018), however this was not seen in controls. Conclusion: An episode of pneumococcal meningitis results in a long-term decrement in overall health related quality of life and is significantly related to hearing loss. [source] | ||||||||||