84. A High Prevalence of Asymptomatic Carriage Complicates Diagnosis of Mycoplasma pneumoniae Respiratory Tract Infections in Children
Session: Oral Abstract Session: Community-Acquired Pneumonia in Children
Thursday, October 18, 2012: 9:30 AM
Room: SDCC 26 AB
Background:

Mycoplasma pneumoniae is considered a major cause of upper and lower respiratory tract infections (RTIs) and disease (RTD) in humans, and particularly in children. Over one third of the childhood cases of community-acquired pneumonia that require hospitalisation are thought to be caused by M. pneumoniae. The diagnosis of Mycoplasma pneumoniae respiratory tract infections (RTIs) currently relies on serological methods and/or the detection of bacterial DNA in the upper respiratory tract (URT). It is conceivable, however, that these diagnostic methods also yield positive results if M. pneumoniae is carried asymptomatically in the URT. Positive results from these tests may therefore not always be indicative of a symptomatic infection. Since the existence of asymptomatic carriage with M. pneumoniae has not been established unequivocally, we set out to determine the presence of M. pneumoniae in the URT of asymptomatic children as well as children with RTI symptoms.

Methods:

In a three-year period from 405 asymptomatic children and 321 children with RTI symptoms (age 3 months-16 years), clinical data, pharyngeal and nasopharyngeal swabs, and serum samples were collected. Serum-antibodies against M. pneumoniae were determined by ELISA and nucleic acids of M. pneumoniae as well as viral respiratory pathogens were identified and quantified by real-time PCR. Bacterial respiratory pathogens (including M. pneumoniae) were detected by culture. M. pneumoniae-positive patients were sampled longitudinally.

Results:

M. pneumoniae DNA was detected in 21% of the asymptomatic children and in 16% of the symptomatic children. Neither serology nor quantitative PCR differentiated asymptomatic carriage from infection. A poor correlation was found between data obtained by PCR and serology. A high rate of multiple, co-existing bacterial and viral pathogens was found in both asymptomatic and symptomatic children.

Conclusion:

The presence of M. pneumoniae in the URT is common in asymptomatic children. The current diagnostic tests for M. pneumoniae are therefore unable to differentiate between asymptomatic carriage and symptomatic infection. We advise caution in the interpretation of results of these diagnostic methods and their use in clinical management.

Emiel Spuesens, MD1, Pieter Fraaij, MD, PhD2, Eline Visser3, Theo Hoogenboezem4, Wim Hop, Ir5, Martin Schutten, PhD6, Henriette Mol, MD, PhD1, Alex van Belkum, PhD7, Albert Osterhaus8, Nico Hartwig, MD, PhD9, Cornelis Vink, PhD10 and Annemarie van Rossum, MD, PhD9, (1)Pediatrics, Erasmus Medical Center, Rotterdam, Netherlands, (2)Virology, Erasmus University Medical Center, Rotterdam, Netherlands, (3)Pediatric Infectious Diseases and Immunology, Erasmus University Medical Center-Sophia Children's Hospital, Rotterdam, Netherlands, (4)Laboratory of Pediatrics, Erasmus University Medical Center, Rotterdam, Netherlands, (5)Statistics, Erasmus University Medical Center, Rotterdam, Netherlands, (6)Virology, Erasmus Medical Center, Rotterdam, Netherlands, (7)Biomerieux, La Balme les Grottes, France, (8)Rotterdam, Netherlands, (9)Pediatric Infectious Diseases and Immunology, Erasmus Medical Center, Rotterdam, Netherlands, (10)Laboratory of Pediatrics, Erasmus Medical Center, Rotterdam, Netherlands

Disclosures:

E. Spuesens, None

P. Fraaij, None

E. Visser, None

T. Hoogenboezem, None

W. Hop, None

M. Schutten, None

H. Mol, None

A. van Belkum, None

A. Osterhaus, None

N. Hartwig, None

C. Vink, None

A. van Rossum, None

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