Chlamydia pneumoniae: Possible Association With Asthma in Children

Chlamydia pneumoniae has been recognized as a common cause of community-acquired pneumonia (CAP) and other acute respiratory infections (ARIs) in various age groups [1]. Lately, the prevalence of Chlamydia-associated ARIs has decreased to <1.5% [2], as a result of changes in epidemiology of C. pneumoniae and increased specificity of new diagnostic molecular methods. Moreover, C. pneumoniae infection may remain undetected as clinicians may not screen the infected population. Indeed, Chlamydia pneumoniae has been recently identified as an agent of asthma exacerbation and has been associated with its severity [3–5], thus reinforcing the importance of targeting these patients. In Lausanne, using a duplex real-time polymerase chain reaction (PCR) that detects C. pneumoniae and Mycoplasma pneumoniae DNA [6], we reported a 0.13% prevalence of C. pneumoniae–positive PCRs (2/1583) and identified 1 patient with C. pneumoniae–associated asthma, who recovered with antibiotics [7]. Below, we report a case series of C. pneumoniae respiratory infections in children. From 10 September to 5 December 2013, C. pneumoniae was detected in upper respiratory tract specimens from 8 children (Table 1). Of these, 5 were admitted for either acute asthma exacerbation or asthmatic bronchitis. All but 2 patients presented with chronic cough without fever or systemic symptoms. These two patients, one with CAP who was coinfected with M. pneumoniae (patient 7) and the other one with severe asthma exacerbation who was coinfected with rhinovirus (patient 8), were admitted for severe respiratory distress in the intensive care unit, intubated, and mechanically ventilated. Both patients with severe clinical presentation were confirmed asthmatics. All patients were successfully treated with a macrolide. Interestingly, C. pneumoniae infection was detected by chance in 7 patients as a result of the dual format of our PCR, because a M. pneumoniae PCR was requested. Baseline Characteristics of Children Identified With C. pneumoniae Abbreviations: ICU, intensive care unit admission; NP, nasopharyngeal. a Patient 7 was admitted to the ICU for community-acquired pneumonia; patient 8, for a severe asthma exacerbation. b Patient originated from the same eastern region of Vaud canton (nearby Yverdon). Baseline Characteristics of Children Identified With C. pneumoniae Abbreviations: ICU, intensive care unit admission; NP, nasopharyngeal. a Patient 7 was admitted to the ICU for community-acquired pneumonia; patient 8, for a severe asthma exacerbation. b Patient originated from the same eastern region of Vaud canton (nearby Yverdon). In conclusion, this report supports the role of C. pneumoniae in asthma exacerbation. Whether C. pneumoniae-associated asthma may be cured with antibiotics or will also require steroids remains unknown and may vary from patient to patient. This case series underlines the importance of screening asthmatic children for C. pneumoniae. Moreover, our findings suggest that C. pneumoniae prevalence is likely underestimated and children with chronic cough, even in absence of fever, should be tested for C. pneumoniae. Potential conflicts of interest. All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.