Nasopharyngeal Carriage Rate and Serotypes of Streptococcus pneumoniae and Antimicrobial Susceptibility in Healthy Korean Children Younger than 5 Years Old: Focus on Influence of Pneumococcal Conjugate Vaccination

BACKGROUND: Even after pneumococcal vaccination introduction, Streptococcus pneumoniae (pneumoccocus) is still an important cause of respiratory and invasive severe infection. Pneumococcus is resided in nasal mucosa and local or systemic infection begins with the nasal mucosa damage. We studied the indirect effect of pneumococcal conjugate vaccine (PCV) on pneumococcal nasopharyngeal carriage rates, serotypes and antimicrobial susceptibility between vaccinate and non-vaccinated children. MATERIALS AND METHODS: From January 2010 to October 2010, 379 healthy children under 5 years old from three university hospitals were recruited. Fully vaccinated children over 3 time doses of PCV and children with no vaccination history of PCV were enrolled, and nasopharyngeal aspirations were obtained from these children. Serotypes using multibead serotyping assay with multiplex PCR and antimicrobial susceptibility was analyzed. Antimicrobial susceptibilities were determined by the CLIS guideline. RESULTS: Two hundred seventy six children were received pneumococcal vaccination while 103 were not. 137 pneumococci were isolated from nasopharyngeal aspiration specimens. Nasal carriage rate was significantly low in vaccinated group (P-value; 0.001). Nasopharyngeal carriage rate was 28.6% (79/276) in vaccinate group and 56.3% (58/103) in non-vaccinated group. Among those vaccinated group, 13.0% (36/276) of the serotypes were vaccine or vaccine related type with the most common type 19F. In contrast, 31.1% (32/103) of the serotypes in non vaccinated group were vaccine or vaccine related type with the most common type 6A. The resistant rate of penicillin was 90.5%. For antimicrobial susceptibility, amoxicillin and amoxicillin/clavulanate showed high susceptibility (73.0%), but 19F and 19A serotypes were all resistant against amoxicillin. CONCLUSIONS: High nasopharyngeal carriage rate in non vaccinated group corresponded to the result of past study. However, 19F and 19A still came up as problematic serotypes with a high carriage rate and antimicrobial resistance in both vaccinated and non vaccinated groups. Also, this study showed that the resistance rate of primary oral antimicrobial agents was increased in compared to past. For solving these problems, the selective antimicrobial use with establishment of high dose amoxicillin/clavulanate regimen and active PCV immunization should be needed. Furthermore, pneumococcal carriage and serotype study concerning with antimicrobial susceptibility should be conducted in the future in 10 or 13-valent PCV received children.

Follow-up of Full-term Neonatal Seizures: Prognostic Factors for Neurodevelopmental Sequelae

PURPOSE: The objectives of this study were to observe the major neurodevelopmental sequelae of the full-term neonatal seizures, and to identify the risk factors associated with the poor neurodevelopmental outcomes. METHODS: A retrospective review of the medical records of full-term newborns who had clinical and/or electrographic seizures in neonatal intensive care unit of St. Mary's Hospital between June 1994 to July 2007 was performed. To assess the risk factors associated with poor neurological outcome, various factors were analyzed with univariate analysis and multiple regression analysis (SAS for Windows version 9.2). RESULTS: The most common etiology of seizures in full-term infants was hypoxic ischemic encephalopathy (76.2%). The most common type of seizure was subtle (50.9%), followed by multifocal clonic (41.8%), and the seizure type had no significant correlation to the prognosis. Moderate to major EEG abnormalities were significantly related to poor clinical outcome. Additional factors related to neurodevelopmental outcome were Apgar score at five minute, evidence of HIE on brain MRI, Sarnat stages of HIE, number of anticonvulsant drugs used for seizure control and duration for normalization of EEG abnormalities. CONCLUSION: The risk factors observed in this study may be helpful to predict the neurological outcomes in full-term neonates with seizures.

Partial Seizures Manifesting as Apnea Only in Preterm Infant

PURPOSE: Extremely-low-birth-weight infants (ELBWIs), especially those or =26-GW (n=65) infants nursed in 60% humidity. RESULTS: Survival rate until discharge was 33%, 82%, 75%, and 89.3% in 22-GW, 23-GW, 24-GW, and > or =26-GW infants, respectively. Fluid intake and IWL was higher in 22-GW and 23-WG, but not different in 24-GW, than in > or =26-GW infants. At postnatal days (P) 3-5, the urine output was significantly lower in > or =26-GW infants than in the other age groups. Serum sodium level was significantly higher in 22-, 23-, and 24-GW (P1-2) than in > or =26-GW infants. Hypernatremia (>150 mEq/dl sodium) was more frequent in 22-GW (71%), 23-GW (41%), and 24-GW (21%) than in > or =26-GW infants (14%). CONCLUSION: High-humidity environments significantly decreased fluid intake and improved electrolyte imbalance in 24-GW, but not 22- and 23-GW, infants. Increased IWL in the latter might be related to more immature skin, and implicates the need for additional nurturing conditions.