Nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from Mozambique.

<h4>Background</h4>Current diagnostic methods for detection of Streptococcus pneumoniae in children with suspected invasive pneumococcal disease have limitations of accuracy, timeliness, and patient convenience. This study aimed to determine the performance of pneumococcal load quantifie...

Full description

Saved in:
Bibliographic Details
Main Authors: Pedro Brotons, Quique Bassat, Miguel Lanaspa, Desiree Henares, Amaresh Perez-Arguello, Lola Madrid, Reyes Balcells, Sozinho Acacio, Maria Andres-Franch, Maria Angeles Marcos, Ana Valero-Rello, Carmen Muñoz-Almagro
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0184762&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849766329407504384
author Pedro Brotons
Quique Bassat
Miguel Lanaspa
Desiree Henares
Amaresh Perez-Arguello
Lola Madrid
Reyes Balcells
Sozinho Acacio
Maria Andres-Franch
Maria Angeles Marcos
Ana Valero-Rello
Carmen Muñoz-Almagro
author_facet Pedro Brotons
Quique Bassat
Miguel Lanaspa
Desiree Henares
Amaresh Perez-Arguello
Lola Madrid
Reyes Balcells
Sozinho Acacio
Maria Andres-Franch
Maria Angeles Marcos
Ana Valero-Rello
Carmen Muñoz-Almagro
author_sort Pedro Brotons
collection DOAJ
description <h4>Background</h4>Current diagnostic methods for detection of Streptococcus pneumoniae in children with suspected invasive pneumococcal disease have limitations of accuracy, timeliness, and patient convenience. This study aimed to determine the performance of pneumococcal load quantified with a real-time polymerase-chain reaction in nasopharyngeal samples to diagnose invasive pneumococcal disease in children.<h4>Methods</h4>Matched case-control study of patients <5 years of age with invasive pneumococcal disease admitted to the Manhiça District Hospital (Mozambique) and asymptomatic controls recruited in different periods between 2006 and 2014. Cases were confirmed by a positive bacterial culture for S. pneumoniae in blood or cerebrospinal fluid. Nasopharyngeal aspirates were collected from cases and controls and pneumococcal density was quantified by lytA real-time polymerase-chain reaction.<h4>Results</h4>Thirty cases (median age 12.8 months) and sixty controls (median age 11.7 months) were enrolled and 70% of them were male. Nasopharyngeal pneumococcal carriage was high in both groups: 28/30 (93.3%) for cases vs. 53/60 (88.3%) for controls (p = 0.71). Mean nasopharyngeal pneumococcal load was identified as a marker for invasive pneumococcal disease (7.0 log10 copies/mL in cases vs. 5.8 log10 copies/mL in controls, p<0.001) and showed good discriminatory power (AUC-ROC: 82.1%, 95% CI 72.5%-91.8%). A colonization density of 6.5 log10 copies/mL was determined as the optimal cut-off value to distinguish cases from controls (sensitivity 75.0%, specificity 73.6%).<h4>Conclusion</h4>Use of non-invasive nasopharyngeal aspirates coupled with rapid and accurate quantification of pneumococcal load by real-time polymerase chain reaction has the potential to become a useful surrogate marker for early diagnosis of invasive pneumococcal disease in children.
format Article
id doaj-art-9718845152bd4549b1a4b091ecc7da64
institution DOAJ
issn 1932-6203
language English
publishDate 2017-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj-art-9718845152bd4549b1a4b091ecc7da642025-08-20T03:04:36ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01129e018476210.1371/journal.pone.0184762Nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from Mozambique.Pedro BrotonsQuique BassatMiguel LanaspaDesiree HenaresAmaresh Perez-ArguelloLola MadridReyes BalcellsSozinho AcacioMaria Andres-FranchMaria Angeles MarcosAna Valero-RelloCarmen Muñoz-Almagro<h4>Background</h4>Current diagnostic methods for detection of Streptococcus pneumoniae in children with suspected invasive pneumococcal disease have limitations of accuracy, timeliness, and patient convenience. This study aimed to determine the performance of pneumococcal load quantified with a real-time polymerase-chain reaction in nasopharyngeal samples to diagnose invasive pneumococcal disease in children.<h4>Methods</h4>Matched case-control study of patients <5 years of age with invasive pneumococcal disease admitted to the Manhiça District Hospital (Mozambique) and asymptomatic controls recruited in different periods between 2006 and 2014. Cases were confirmed by a positive bacterial culture for S. pneumoniae in blood or cerebrospinal fluid. Nasopharyngeal aspirates were collected from cases and controls and pneumococcal density was quantified by lytA real-time polymerase-chain reaction.<h4>Results</h4>Thirty cases (median age 12.8 months) and sixty controls (median age 11.7 months) were enrolled and 70% of them were male. Nasopharyngeal pneumococcal carriage was high in both groups: 28/30 (93.3%) for cases vs. 53/60 (88.3%) for controls (p = 0.71). Mean nasopharyngeal pneumococcal load was identified as a marker for invasive pneumococcal disease (7.0 log10 copies/mL in cases vs. 5.8 log10 copies/mL in controls, p<0.001) and showed good discriminatory power (AUC-ROC: 82.1%, 95% CI 72.5%-91.8%). A colonization density of 6.5 log10 copies/mL was determined as the optimal cut-off value to distinguish cases from controls (sensitivity 75.0%, specificity 73.6%).<h4>Conclusion</h4>Use of non-invasive nasopharyngeal aspirates coupled with rapid and accurate quantification of pneumococcal load by real-time polymerase chain reaction has the potential to become a useful surrogate marker for early diagnosis of invasive pneumococcal disease in children.https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0184762&type=printable
spellingShingle Pedro Brotons
Quique Bassat
Miguel Lanaspa
Desiree Henares
Amaresh Perez-Arguello
Lola Madrid
Reyes Balcells
Sozinho Acacio
Maria Andres-Franch
Maria Angeles Marcos
Ana Valero-Rello
Carmen Muñoz-Almagro
Nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from Mozambique.
PLoS ONE
title Nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from Mozambique.
title_full Nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from Mozambique.
title_fullStr Nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from Mozambique.
title_full_unstemmed Nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from Mozambique.
title_short Nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from Mozambique.
title_sort nasopharyngeal bacterial load as a marker for rapid and easy diagnosis of invasive pneumococcal disease in children from mozambique
url https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0184762&type=printable
work_keys_str_mv AT pedrobrotons nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT quiquebassat nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT miguellanaspa nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT desireehenares nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT amareshperezarguello nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT lolamadrid nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT reyesbalcells nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT sozinhoacacio nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT mariaandresfranch nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT mariaangelesmarcos nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT anavalerorello nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique
AT carmenmunozalmagro nasopharyngealbacterialloadasamarkerforrapidandeasydiagnosisofinvasivepneumococcaldiseaseinchildrenfrommozambique