A Retrospective Study of Invasive Bacterial Infections in Children with Asplenia

PURPOSE: Because children with asplenia have an increased risk of fulminant infection associated with a high fatality, chemoprophylaxis, and vaccinations against encapsulated bacteria are recommended. However, there have been few reports of the burden of severe bacterial infection and the current status of chemoprophylaxis and immunization among children with asplenia in Korea. METHODS: We conducted a retrospective study including children with asplenia who were treated at our institute between January 1997 and December 2016. RESULTS: From a total of 213 children with asplenia, 114 (53.5%) had congenital asplenia and 58 (27.2%) had functional asplenia. The remaining 41 (19.3%) had acquired asplenia with the median age at splenectomy being 12.2 years (range, 5.0 to 16.9 years); the most common cause of splenectomy was hereditary spherocytosis (39.0%). The chemoprophylaxis rate was 16.4%. The immunization rates were 44.1% for pneumococcus, 53.0% for Haemophilus influenzae type B, and 10.7% for meningococcus. The incidence of invasive bacterial infection among children with asplenia was 0.28/100 person-year; a total of six episodes (2.8%) were observed in five patients with congenital asplenia and one patient with functional asplenia. The median age for these infections was 15 months (range, 4 to 68 months). Five of the six episodes were bacteremia, and the other was meningitis. The most common pathogen was Streptococcus pneumoniae (n=3), followed by H.influenzae (n=1). Three of the six patients (50.0%) died, all of whom had pneumococcal bacteremia. None of the six had chemoprophylaxis or proper vaccinations. CONCLUSIONS: Although there is an increased risk of a severe infection proper vaccinations and chemoprophylaxis are still lacking. Physicians should be encouraged to implement appropriate chemoprophylaxis and immunizations for patients with asplenia.

A Retrospective Analysis of Characteristics of Probiotics Associated with Invasive Bacterial Infections in Children

PURPOSE: The purpose of this study was to analyze the clinical features and risk factors of invasive infections caused by Lactobacillus spp. and Saccharomyces spp., components of commercially available probiotics. METHODS: We analyzed demographic and clinical data from children ≤18 years of age with an invasive infection caused by Lactobacillus spp. or Saccharomyces spp. at the Asan Medical Center Children's Hospital from January 1998 to June 2016. Probiotic consumption data were also analyzed. RESULTS: During the study period, a total of 24 episodes of invasive infections were caused by Lactobacillus spp. (n=16) and Saccharomyces cerevisiae (n=8). Along with the increase of probiotic use (755,594 [days/1,000 patient-admission days] in 2001 to 2005, 1,444,066 in 2006 to 2010, and 6,904,736 in 2011 to 2016), the incidence of probiotic-associated invasive infection increased (R2=0.70). The median age of the patients was 1.8 years (range, 2 months to 17 years), and most of them had underlying medical conditions. The 30-day mortality rate was 20.8% (5/24), and 11 (45.8%) of these patients resulted from a severe invasive infection. We determined the risk factors for invasive infection to be: previous intensive care unit stay (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.5 to 6.1] and the presence of a central venous catheter (OR, 2.2; 95% CI, 1.2 to 4.3). CONCLUSIONS: Although the probiotic-associated invasive infections rarely occurred in children, the incidence has increased along with probiotic pressure. Judicious use of probiotics is mandatory, especially in young children with underlying medical conditions and continuous surveillance will be needed to minimize the safety concerns.

A Retrospective Study of Invasive Bacterial Infections in Children with Asplenia

PURPOSE: Because children with asplenia have an increased risk of fulminant infection associated with a high fatality, chemoprophylaxis, and vaccinations against encapsulated bacteria are recommended. However, there have been few reports of the burden of severe bacterial infection and the current status of chemoprophylaxis and immunization among children with asplenia in Korea. METHODS: We conducted a retrospective study including children with asplenia who were treated at our institute between January 1997 and December 2016. RESULTS: From a total of 213 children with asplenia, 114 (53.5%) had congenital asplenia and 58 (27.2%) had functional asplenia. The remaining 41 (19.3%) had acquired asplenia with the median age at splenectomy being 12.2 years (range, 5.0 to 16.9 years); the most common cause of splenectomy was hereditary spherocytosis (39.0%). The chemoprophylaxis rate was 16.4%. The immunization rates were 44.1% for pneumococcus, 53.0% for Haemophilus influenzae type B, and 10.7% for meningococcus. The incidence of invasive bacterial infection among children with asplenia was 0.28/100 person-year; a total of six episodes (2.8%) were observed in five patients with congenital asplenia and one patient with functional asplenia. The median age for these infections was 15 months (range, 4 to 68 months). Five of the six episodes were bacteremia, and the other was meningitis. The most common pathogen was Streptococcus pneumoniae (n=3), followed by H.influenzae (n=1). Three of the six patients (50.0%) died, all of whom had pneumococcal bacteremia. None of the six had chemoprophylaxis or proper vaccinations. CONCLUSIONS: Although there is an increased risk of a severe infection proper vaccinations and chemoprophylaxis are still lacking. Physicians should be encouraged to implement appropriate chemoprophylaxis and immunizations for patients with asplenia.

A Retrospective Analysis of Characteristics of Probiotics Associated with Invasive Bacterial Infections in Children

PURPOSE: The purpose of this study was to analyze the clinical features and risk factors of invasive infections caused by Lactobacillus spp. and Saccharomyces spp., components of commercially available probiotics. METHODS: We analyzed demographic and clinical data from children ≤18 years of age with an invasive infection caused by Lactobacillus spp. or Saccharomyces spp. at the Asan Medical Center Children's Hospital from January 1998 to June 2016. Probiotic consumption data were also analyzed. RESULTS: During the study period, a total of 24 episodes of invasive infections were caused by Lactobacillus spp. (n=16) and Saccharomyces cerevisiae (n=8). Along with the increase of probiotic use (755,594 [days/1,000 patient-admission days] in 2001 to 2005, 1,444,066 in 2006 to 2010, and 6,904,736 in 2011 to 2016), the incidence of probiotic-associated invasive infection increased (R2=0.70). The median age of the patients was 1.8 years (range, 2 months to 17 years), and most of them had underlying medical conditions. The 30-day mortality rate was 20.8% (5/24), and 11 (45.8%) of these patients resulted from a severe invasive infection. We determined the risk factors for invasive infection to be: previous intensive care unit stay (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.5 to 6.1] and the presence of a central venous catheter (OR, 2.2; 95% CI, 1.2 to 4.3). CONCLUSIONS: Although the probiotic-associated invasive infections rarely occurred in children, the incidence has increased along with probiotic pressure. Judicious use of probiotics is mandatory, especially in young children with underlying medical conditions and continuous surveillance will be needed to minimize the safety concerns.

Successful Allogeneic Hematopoietic Stem Cell Transplantation for a Patient with Very Severe Aplastic Anemia During Active Invasive Fungal Infection / 임상소아혈액종양

Allogeneic hematopoietic stem cell transplantation (HSCT) may not be considered feasible in a patient with active fungal infection due to transplant-related mortality. We report a case of HSCT performed on a 6-month-old girl, who was diagnosed with very severe aplastic anemia (vSAA) at the age of 2 months, during active invasive pulmonary aspergillosis (IPA). Despite receiving continuous antifungal treatment and multiple granulocyte infusions, her IPA was aggravated. She underwent allogeneic HSCT from a matched sibling donor using conditioning regimen of fludarabine, reduced dose of cyclophosphamide, and anti-thymocyte globulin (ATG) during IPA. After neutrophil engraftment, fever subsided and IPA improved. She was continued on voriconazole for 7 months after HSCT. She is alive with normal hematopoiesis 4 years post-transplant. Our report suggests that allogeneic HSCT using conditioning regimen of fludarabine, reduced dose of cyclophosphamide, and ATG can be a feasible option for the patients with vSAA even during active fungal infection.

Prediction of unresponsiveness to second intravenous immunoglobulin treatment in patients with Kawasaki disease refractory to initial treatment / 소아과

PURPOSE: This study investigated predictors of unresponsiveness to second-line intravenous immunoglobulin (IVIG) treatment for Kawasaki disease (KD). METHODS: This was a single-center analysis of the medical records of 588 patients with KD who had been admitted to Asan Medical Center between 2006 and 2014. Related clinical and laboratory data were analyzed by univariate and multivariate logistic regression analyses. RESULTS: Eighty (13.6%) of the 588 patients with KD were unresponsive to the initial IVIG treatment and received a second dose. For these 80 patients, univariate analysis of the laboratory results obtained before administering the second-line IVIG treatment showed that white blood cell count, neutrophil percent, hemoglobin level, platelet count, serum protein level, albumin level, potassium level, and C-reactive protein level were significant predictors. The addition of methyl prednisolone to the second-line regimen was not associated with treatment response (odds ratio [OR], 0.871; 95% confidence interval [CI], 0.216–3.512; P=0.846). Multivariate analysis revealed serum protein level to be the only predictor of unresponsiveness to the second-line treatment (OR, 0.160; 95% CI, 0.028–0.911; P=0.039). Receiver operating characteristic curve analysis to determine predictors of unresponsiveness to the second dose of IVIG showed a sensitivity of 100% and specificity of 72% at a serum protein cutoff level of <7.15 g/dL. CONCLUSION: The serum protein level of the patient prior to the second dose of IVIG is a significant predictor of unresponsiveness. The addition of methyl prednisolone to the second-line regimen produces no treatment benefit.

Successful Allogeneic Hematopoietic Stem Cell Transplantation for a Patient with Very Severe Aplastic Anemia During Active Invasive Fungal Infection / 임상소아혈액종양

Allogeneic hematopoietic stem cell transplantation (HSCT) may not be considered feasible in a patient with active fungal infection due to transplant-related mortality. We report a case of HSCT performed on a 6-month-old girl, who was diagnosed with very severe aplastic anemia (vSAA) at the age of 2 months, during active invasive pulmonary aspergillosis (IPA). Despite receiving continuous antifungal treatment and multiple granulocyte infusions, her IPA was aggravated. She underwent allogeneic HSCT from a matched sibling donor using conditioning regimen of fludarabine, reduced dose of cyclophosphamide, and anti-thymocyte globulin (ATG) during IPA. After neutrophil engraftment, fever subsided and IPA improved. She was continued on voriconazole for 7 months after HSCT. She is alive with normal hematopoiesis 4 years post-transplant. Our report suggests that allogeneic HSCT using conditioning regimen of fludarabine, reduced dose of cyclophosphamide, and ATG can be a feasible option for the patients with vSAA even during active fungal infection.