Culture-Independent Analysis of Pediatric Bronchoalveolar Lavage Specimens
ANNALS OF THE AMERICAN THORACIC SOCIETY
Zachariah, P., Ryan, C., Nadimpalli, S., Coscia, G., Kolb, M., Smith, H., Foca, M., Saiman, L., Planet, P. J.
2018; 15 (9): 1047?56
Abstract
The clinical utility of culture-independent testing of pediatric BAL specimens is unknown. In addition, the variability of the pediatric pulmonary microbiome with patient characteristics is not well understood.To compare testing with 16S rRNA gene-based sequencing to conventional cultures of BAL specimens in children Methods: Study subjects were not more than 22 years old and underwent BAL from May 2013 to August 2015 as part of clinical care. DNA extracted from BAL specimens was used for 16S rRNA gene-based analysis, and results were compared with routine cultures from the same samples. Indices of microbial diversity and relative taxon abundances were compared on the basis of subject characteristics (diagnosis and antibiotic use).From 81 participants (male, 51%; median age, 9 yr), 89 samples were collected. The 16S rRNA genes of 77 samples (86.5%) from 70 subjects were successfully analyzed. These 70 subjects included 23 with cystic fibrosis, 19 who were immunocompromised, and 28 who were nonimmunocompromised. Of 68 organisms identified in culture, 16S rRNA gene-based analyses detected corresponding taxa in 66 (97.1%) and also identified potentially clinically significant organisms missed by cultures (e.g., Staphylococcus, Legionella, and Pseudomonas). Taxa that varied significantly with diagnosis and antibiotic use included Veillonella, Corynebacterium, Haemophilus, and Streptococcus. The microbiota of cystic fibrosis samples was less diverse. A "core" group of 15 taxa present in all three diagnosis groups was identified.Culture-independent analysis was concordant with routine cultures and showed the potential to detect noncultured pathogens. Although culture-independent testing identified relative changes in organism abundance associated with clinical characteristics, distinct microbiome profiles associated with disease states were not identified.
View details for DOI 10.1513/AnnalsATS.201802-146OC
View details for Web of Science ID 000447989500008
View details for PubMedID 29877714
Abstract
The diagnostic yield of bronchoalveolar lavage (BAL) in the Immunocompromised pediatric population has ranged from 28% to 68%. We hypothesized that the diagnostic yield of BALs would be higher in more recent years due to new diagnostic assays.A retrospective case series was performed among immunocompromised children ?18 years old who underwent BALs from 2001 to 2012, to assess the yield of microbiologic diagnostic studies and to determine the impact of BAL findings on antimicrobial management.In all, 123 subjects underwent 174 BALs (mean age 9.9 years). Underlying diagnoses included both malignant (n?=?79) and non-malignant (n?=?44) disorders, and 75 (61.0%) subjects were hematopoietic stem cell transplant (HSCT) recipients. Fifty-four (31.0%) of 174 BAL were positive for ?1 potential pathogen (n?=?58 microorganisms). The diagnostic yield of BALs performed from 2001 to 2006 versus2007-2012 was similar (40.5% vs. 26.6%, respectively, P?=?0.07). Most subjects (86.2%) were on ?1 antimicrobial at the time of BAL. Most (65.8%) negative BALs were associated with narrowing antimicrobial therapy, while most (74.1%) positive BALs were associated with continuing or changing to targeted antimicrobial therapy.In this study population, the diagnostic yield of BAL was similar to that previously described and unchanged in more recent years. Both negative and positive BALs were associated with changes in antimicrobial management.A 10-year retrospective review of bronchoalveolar lavage in 123 immunocompromised children determined that the rate of isolation of potential pathogens was 31% in this population. The majority of BAL was associated with a change in antimicrobial therapy. Pediatr Pulmonol. © 2016 Wiley Periodicals, Inc.
View details for DOI 10.1002/ppul.23644
View details for PubMedID 28052585
Abstract
Surveillance for invasive Aspergillus (IA) in children is complex. We performed a retrospective study (2004-2013) using string searches of relevant terms within histopathology and radiology reports in efforts to improve detection of IA. Overall, 22 children met IA criteria, of whom 5 (23%) were only identified by string searches.
View details for DOI 10.1016/j.ajic.2016.04.230
View details for PubMedID 27375058
Abstract
We describe a case of fetal parvovirus B19 infection resulting in preterm birth and leading to hydrops fetalis requiring multiple in utero transfusions. The infant developed chronic postnatal anemia responsive to intravenous immunoglobulin therapy. Serum viral load decreased after immunoglobulin treatment but remained detectable for over 1 year.
View details for DOI 10.1093/ofid/ofv049
View details for PubMedID 26288800
Department Intranet