Clinical Features and Complications

Clinical Features

Chlamydia pneumoniae infections can occur in the upper or lower respiratory tract. Clinical presentations can vary widely. The incubation period is generally between 3 to 4 weeks; however, shorter times have been documented.

Infection most commonly results in:

• Laryngitis
• Pharyngitis
• Coryza
• Malaise
• Fever
• Cough
• Headache

After gradual onset, symptoms due to C. pneumoniae respiratory infection may continue over extended periods, with persistence of cough and malaise for several weeks or months despite appropriate antibiotic therapy.

C. pneumoniae can be differentiated from Mycoplasma pneumoniae, also a type of atypical bacterial pneumonia, by the presence of laryngitis. Although not all patients with C. pneumoniae pneumonia  develop laryngitis, most do.
 

Clinical Complications

Most respiratory infections caused by C. pneumoniae are asymptomatic or mild, although severe complications can occur that result in hospitalization and sometimes death. Complications that have been reported include:

• Severe pneumonia
• Exacerbation of asthma
• Encephalitis
• Myocarditis

References

• Blasi F, Tarsia P, Aliberti S. Chlamydophila pneumoniae. Clin Microbiol Infect. 2009;15:29–35.

• Burillo A, Bouza E. Chlamydophila pneumoniae. Infect Dis Clin N Am. 2010;24:61–71.
• Cunha BA.  The atypical pneumonias: Clinical diagnosis and importance. Clin Microbio Infect. 2006;12:12–24.