Immunogenicity and safety of primary and secondary DTaP booster vaccination

Diphtheria-tetanus-acellular pertussis (DTaP) vaccination must currently be administered three times starting at 2 months of age, at intervals of two months, with the first and second boosters administered at 15 to 8 months and 4 to 6 years of age. A high rate of vaccination is maintained, but studies of the efficiency and safety of booster vaccination are lacking. This study evaluated the immunogenicity and safety of the DTaP booster vaccine. Seventy-two infants who had been vaccinated with the first booster and 78 children who had been vaccinated with the second booster were enrolled in this study. Local and systemic adverse reactions after vaccination were recorded. Sera obtained before and 1 month after booster vaccination were analyzed for antibodies to diphtheria and tetanus toxoid, and anti-pertussis toxin. Diphtheria: The GMT was increased. Tetanus: The geometric mean antibody titer (GMT) was increased. Pertussis: The GMT was increased by 13.72 times and 14.37 times after the first and the second additional vaccination, respectively. Although the seroconversion rate was low prior to the first booster, the average amount of anti-pertussis toxin antibodies before the first additional vaccination was 143.37 EU/mL, which rose to 261.88 EU/mL after the vaccination. The seroconversion rate also increased to 100%. Adverse reactions showed spontaneous resolution within a few days after vaccination. After the second additional vaccination, there was a statistically significant increase in the manifestation of myalgia compared to after the first additional vaccination. In conclusion, DTaP booster vaccination was effective in Korean children, demonstrating that modifications to the current regimen would be unnecessary.

Nasopharyngeal Pneumococcal Carriage of Children Attending Day Care Centers in Korea: Comparison between Children Immunized with 7-valent Pneumococcal Conjugate Vaccine and Non-immunized

To confirm the effect of 7-valent pneumococcal conjugate vaccine (PCV7), pneumococcal nasopharyngeal (NP) carriage was compared between vaccinated (3 + 1 doses PCV7) and non-vaccinated children. Vaccinated subjects were recruited from highly vaccinated regions (> or = 60%), Seoul and Incheon whereas control subjects were recruited from Jeju Island where vaccination rates are low (< 15%). NP swabs were obtained from 400 children aged 18-59 months. Serotype and antibiotic susceptibility was analyzed. Pneumococcal carriage rate was 18.0% (36/200) and 31.5% (63/200) for the vaccinated and control group, respectively. Among those vaccinated, 41.7% (15/36) of the serotypes were vaccine-related type (VRT: 6A, 6C, 19A) with the most common serotype 6C. The next common type was non-typable/non-capsule 30.6% (11/36) followed by non-vaccine type 16.7% (6/36) and vaccine type (VT) serotypes were found in only 11.1% (4/36). In contrast, 52.4% (33/63) of the isolates in the control group were VT. Resistance rates for penicillin and erythromycin were lower in the vaccine group (vaccine vs control; penicillin 45.2% vs 71.4%, erythromycin 74.2% vs 90.5%, P < 0.05). Multi-drug resistance was also lower in vaccinated subjects (vaccine vs control; 45.2% vs 69.8%, P < 0.05). PCV7 reduces carriage in VT which leads to replacement of pneumococci by antibiotic susceptible VRT or non-vaccine type strains.

Clinical and Phylogenetic Characteristics of Escherichia coli Urinary Tract Infections / 소아감염

PURPOSE: We aimed to investigate the clinical and phylogenetic characteristics of Escherichia coli Urinary Tract Infections (E. coli UTI). METHODS: We enrolled patients with culture-proven E. coli UTI, who were admitted at the study hospital from September 2008 to August 2009. We investigated clinical data of patients with E. coli UTI and characteristics of isolated E. coli strains. The phylogenetic groups were classified using triplex polymerase chain reaction (PCR), and the distribution of nine virulent genes was determined by multiplex PCR. RESULTS: A total of 47 patients have participated in this study. Thirty (63.8%) were under 6 months; eight (17.0%) were between 6-12 months; and nine (19.1%) were over 12 months. We compared two age groups between under 6-month and over 6-month. In the age group under 6-month, higher proportion of male (P=0.002) and group B2 strains (P=0.020) were observed. In contrast, higher proportion of female and group non-B2 strains were observed in age group over 6-month. Frequencies of papC, papGII, papGIII, sfa/foc, hlyC, cnf1, fyuA, iroN and iucC were estimated as 68.1%, 57.4%, 42.6%, 46.8%, 46.8%, 31.9%, 87.2%, 48.9% and 63.8%, respectively. In the comparison of phylogenetic groups, group B2 showed higher distribution of virulent genes, while group D included more strains resistant to trimethoprim/sulfamethoxazole (TMP/SMZ) than other groups. CONCLUSION: We showed the age group-specific difference in the distribution of sex ratios and phylogenetic groups; more male and group B2 strains in age group under 6-month, while more female and group non-B2 in age group over 6-month. However, further evaluation including larger number of patients will be necessary to confirm above thesis in future molecular epidemiological studies.

A case of idiopathic pulmonary hemosiderosis with seasonal recurrence / 소아과

Idiopathic pulmonary hemosiderosis (IPH) is a rare disease affecting mostly children. This disorder is characterized by recurrent episodes of hemoptysis, bilateral diffuse pulmonary infiltrates, and iron-deficiency anemia. An acute fulminant alveolar hemorrhage can be fatal due to respiratory failure, while chronic hemorrhage leads to hemosiderin-laden macrophages and pulmonary fibrosis. Genetic, autoimmune, allergic, environmental, and metabolic mechanisms of pathogenesis have been suggested, but the etiology of IPH remains unknown. We report on a 9-year-old girl with idiopathic pulmonary hemosiderosis who showed seasonal recurrences without cause.

The immunogenicity and reactogenicity of Td booster vaccination in Korean preadolescents, aged with 11-12 years old / 소아과

PURPOSE: This study was undertaken to evaluate the immunogenicity and reactogenicity of Td booster immunization in early preadolescents of Korea. METHODS: Healthy preadolescents, who had been vaccinated with 4 or 5 doses of DTaP vaccines until 6 years old age, were enrolled in this study from August 2006 to April 2007 . Diphtheria and tetanus anti-toxoid antibodies in sera were measured by ELISA just before vaccination and 4 weeks after vaccination to evaluate immunogenicity. Local and systemic adverse reactions observed for 4 weeks after vaccination to access reactogenicity. RESULTS: 183 preadolescents were enrolled and mean age was 11.40+/-0.51 years old. All subjects achieved seroprotective diphtheria and tetanus anti-toxoid antibodies (titers > or =0.1 IU/mL) after Td booster vaccination. Among 183 vaccinees, 73.8% showed local adverse reactions and 37.2% systemic adverse reactions. Pain at injection site (66.1%) was the most common local reaction, and the most commonly shown systemic reaction was myalgia (17.5%). The adverse reactions were spontaneously relieved within three days after vaccination. CONCLUSION: Td vaccine in this study was high immunogenic and showed an acceptable tolerance in Korean preadolescents. Td booster vaccination at 11 -12 years old is the most effective method to increase compliance of the vaccination and to decrease the incidence of diphtheria and tetanus.

Performance effectiveness of pediatric index of mortality 2 (PIM2) and pediatricrisk of mortality III (PRISM III) in pediatric patients with intensive care in single institution: Retrospective study / 소아과

PURPOSE: To investigate the discriminative ability of pediatric index of mortality 2 (PIM2 ) and pediatric risk of mortality III (PRISM III) in predicting mortality in children admitted into the intensive care unit (ICU). METHODS: We retrospectively analyzed variables of PIM2 and PRISM III based on medical records with children cared for in a single hospital ICU from January 2003 to December 2007. Exclusions were children who died within 2 h of admission into ICU or hopeless discharge. We used Students t test and ANOVA for general characteristics and for correlation between survivors and non-survivors for variables of PIM2 and PRISM III. In addition, we performed multiple logistic regression analysis for Hosmer-Lemeshow goodness-of-fit, receiver operating characteristic curve (ROC) for discrimination, and calculated standardized mortality ratio (SMR) for estimation of prediction. RESULTS: We collected 193 medical records but analyzed 190 events because three children died within 2 h of ICU admission. The variables of PIM2 correlated with survival, except for the presence of post-procedure and low risk. In PRISM III, there was a significant correlation for cardiovascular/neurologic signs, arterial blood gas analysis but not for biochemical and hematologic data. Discriminatory performance by ROC showed an area under the curve 0.858 (95% confidence interval; 0.779-0.938) for PIM2, 0.798 (95% CI; 0.686-0.891) for PRISM III, respectively. Further, SMR was calculated approximately as 1 for the 2 systems, and multiple logistic regression analysis showed chi-square(13)=14.986, P=0.308 for PIM2, chi-square(13)=12.899, P=0.456 for PRISM III in Hosmer-Lemeshow goodness-of-fit. However, PIM2 was significant for PRISM III in the likelihood ratio test chi-square(4)=55.3, P<0.01). CONCLUSION: We identified two acceptable scoring systems (PRISM III, PIM2 ) for the prediction of mortality in children admitted into the ICU. PIM2 was more accurate and had a better fit than PRISM III on the model tested.

Correlation between Serum Albumin Level and IgG Level in Minimal Change Nephrotic Syndrome

PURPOSE: Hypogammaglobulinemia has been observed in nephrotic syndrome, but its pathophysiology remains unknown. We evaluated the relationship between the serum IgG and albumin levels for children with minimal change nephrotic syndrome(MCNS). METHODS: The levels of immunoglobulin G(IgG), albumin and total cholesterol of a total of 46 children with MCNS(proteinuria >40 mg/m2/h, and serum albumin level <2.5 g/dL) were analyzed. RESULTS: The mean values of albumin, IgG and total cholesterol in MCNS children were 1.7+/-0.3 g/dL, 368+/-143 mg/dL and 431+/-78 mg/dL, respectively. There was an inverse correlation between the albumin values and the total cholesterol values(r=0.68, P=0.0001), whereas there was a direct-proportional correlation between albumin values and the IgG values(r=0.4, P=0.01). CONCLUSION: The IgG level is associated with albumin level, and it may reflect the severity of urinary protein loss in MCNS. Further studies are needed to evaluate this phenomenon.