MedlinePlus Medical Encyclopedia: Psittacosis

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Psittacosis

Contents of this page:
Illustrations Alternative names Definition Causes, incidence, and risk factors Symptoms Signs and tests	Treatment Expectations (prognosis) Complications Calling your health care provider Prevention

Illustrations

Lungs

Respiratory system

Alternative names Return to top

Ornithosis; Chlamydia psittaci

Definition Return to top

Psittacosis is an infection caused by the bacterium Chlamydia psittaci, which is spread to humans by birds, causing systemic (throughout the body) symptoms and pneumonia.

Causes, incidence, and risk factors Return to top

Psittacosis is caused by Chlamydia psittaci, a bacterium found in the droppings of birds. It is a rare disease-- fewer than 50 cases have been reported in the U.S. in the past 5 years.

Bird owners, pet shop employees, workers in poultry processing plants, and veterinarians are at increased risk for acquiring this infection.

Symptoms Return to top

Fever and chills
Muscle aches
Headache
Fatigue
Dry cough
Shortness of breath
Rales may be present
Blood-tinged sputum

Signs and tests Return to top

Abnormal lung sounds such as rales and decreased breath sounds are heard when listening to the chest with a stethoscope.

Tests include:

X-ray of the chest (interstitial infiltrates)
CT scan of the chest
Blood gas (decreased oxygen saturation)
Sputum culture
Blood culture (grows chlamydia)
Antibody titer

Treatment Return to top

The infection is treated with antibiotics, including:

Tetracycline
Doxycycline
Erythromycin
Azithromycin

Note: Oral tetracycline is usually not prescribed for children until after all the permanent teeth have erupted. It can permanently discolor teeth that are still forming.

Expectations (prognosis) Return to top

Full recovery is expected.

Complications Return to top

Decreased pulmonary function as a result of the pneumonia
Heart valve infection
Hepatitis (inflammation of the liver)
Brain involvement

Calling your health care provider Return to top

Antibiotics are needed to treat this infection. If you develop symptoms suggestive of psittacosis, call your health care provider.

Prevention Return to top

Avoid exposure to suspect birds (often imported parakeets and similar birds carry this bacterium). Treat underlying medical problems that cause immune dysfunction and increase susceptibility to this disease.

Update Date: 6/20/2004

Updated by: Jacqueline A. Hart, M.D., Senior Medical Editor, A.D.A.M., Inc., and Christopher Parsons, M.D., Department of Internal Medicine, Division of Infectious Diseases, University of Virginia, Charlottesville, VA. Review provided by VeriMed Healthcare Network (7/31/2002).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2002 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.