Type your tag names separated by a space and hit enter

Chlamydophila (Formerly Chlamydia) Pneumoniae Infection

Chlamydophila (Formerly Chlamydia) Pneumoniae Infection is a topic covered in the 5-Minute Pediatric Consult.

To view the entire topic, please or purchase a subscription.

Pediatrics Central™ is an all-in-one application that puts valuable medical information, via your mobile device or the web, in the hands of clinicians treating infants, children, and adolescents. Explore these free sample topics:

Pediatrics Central

-- The first section of this topic is shown below --



Chlamydiae are obligate intracellular organisms classified as bacteria but which possess qualities of both bacteria and viruses. They cause a variety of infections from the respiratory to the urogenital tract. The genus has been divided into Chlamydia (Chlamydia trachomatis, others) and Chlamydophila (Chlamydophila pneumoniae, Chlamydophila psittaci, others). Three species are known to affect humans:

  • C. trachomatis: a leading cause of sexually transmitted infections in the United States, which can be vertically transmitted during childbirth
  • C. psittaci: a rare zoonosis
  • C. pneumoniae: an important cause of respiratory infections in the school-aged child; will be the focus of this chapter


  • Spread person to person by respiratory droplets; no seasonal trend
  • Asymptomatic carriage and prolonged nasopharyngeal shedding occurs.
  • Peak ages of infection are 5 to 15 years.
  • Coinfection with other respiratory pathogens is common.
  • Serum antibodies are positive in about 50% of adults by age 20 years, and reinfection commonly occurs in adults.

Risk Factors

School-aged children are at highest risk.

General Prevention

Cough etiquette (coughing into elbow or tissue) and proper hand hygiene are important control measures.


  • Chlamydiae exist in two forms:
    • Elementary body (EB): infectious form
    • Reticulate body (RB): reproductive form
  • Life cycle:
    • EB is taken into cell by endocytosis and reorganizes into an RB to replicate.
    • After replication, RB transformed to EB and are released by exocytosis or cytolysis.
    • Cycle between endocytosis and release is 2 to 3 days.

-- To view the remaining sections of this topic, please or purchase a subscription --


Cabana, Michael D., editor. "Chlamydophila (Formerly Chlamydia) Pneumoniae Infection." 5-Minute Pediatric Consult, 8th ed., Wolters Kluwer, 2019. Pediatrics Central, peds.unboundmedicine.com/pedscentral/view/5-Minute-Pediatric-Consult/618110/all/Chlamydophila__Formerly_Chlamydia__Pneumoniae_Infection.
Chlamydophila (Formerly Chlamydia) Pneumoniae Infection. In: Cabana MD, ed. 5-Minute Pediatric Consult. 8th ed. Wolters Kluwer; 2019. https://peds.unboundmedicine.com/pedscentral/view/5-Minute-Pediatric-Consult/618110/all/Chlamydophila__Formerly_Chlamydia__Pneumoniae_Infection. Accessed April 21, 2019.
Chlamydophila (Formerly Chlamydia) Pneumoniae Infection. (2019). In Cabana, M. D. (Ed.), 5-Minute Pediatric Consult. Available from https://peds.unboundmedicine.com/pedscentral/view/5-Minute-Pediatric-Consult/618110/all/Chlamydophila__Formerly_Chlamydia__Pneumoniae_Infection
Chlamydophila (Formerly Chlamydia) Pneumoniae Infection [Internet]. In: Cabana MD, editors. 5-Minute Pediatric Consult. Wolters Kluwer; 2019. [cited 2019 April 21]. Available from: https://peds.unboundmedicine.com/pedscentral/view/5-Minute-Pediatric-Consult/618110/all/Chlamydophila__Formerly_Chlamydia__Pneumoniae_Infection.
* Article titles in AMA citation format should be in sentence-case
TY - ELEC T1 - Chlamydophila (Formerly Chlamydia) Pneumoniae Infection ID - 618110 ED - Cabana,Michael D, BT - 5-Minute Pediatric Consult UR - https://peds.unboundmedicine.com/pedscentral/view/5-Minute-Pediatric-Consult/618110/all/Chlamydophila__Formerly_Chlamydia__Pneumoniae_Infection PB - Wolters Kluwer ET - 8 DB - Pediatrics Central DP - Unbound Medicine ER -