Key points
- Chlamydia pneumoniae infections can occur in the upper or lower respiratory tract.
- Infections can be asymptomatic, while those with symptoms have a wide clinical presentation.
- Complications are rare but can be serious.
Clinical features
Most respiratory infections caused by C. pneumoniae are asymptomatic or mild.
For those with symptoms, clinical presentations can vary widely.
Most common
People with symptoms of C. pneumoniae infection most commonly present with
- Cough
- Fever
- Headache
- Malaise
Less common
They also can develop:
- Coryza
- Laryngitis
- Pharyngitis
- Pneumonia
Extended, persistent course of illness
After gradual illness onset, symptoms due to C. pneumoniae respiratory infection may continue over extended periods. Patients may experience a persistent cough and malaise for several weeks or months despite appropriate antibiotic therapy. C. pneumoniae can cause chronic infection.
Complications
Although rare, severe complications can occur. These severe complications can result in hospitalization and sometimes death.
Complications include:
- Encephalitis
- Exacerbation of asthma
- Myocarditis
Potential link with other diseases
In the past 20 years, researchers have linked a wide variety of diseases to C. pneumoniae infection including:
- Age-related macular degeneration
- Alzheimer's disease
- Asthma
- Atherosclerotic cardiovascular disease
- Chronic fatigue syndrome
- Chronic skin wounds
- Multiple sclerosis
However, researchers have not been able to confirm a causal relationship between these diseases and C. pneumoniae infection.