Pulmonary nocardiosis

Definition

Pulmonary nocardiosis is an infection of the lung with the bacteria, Nocardia asteroides.

Alternative Names

Nocardiosis - pulmonary

Causes, incidence, and risk factors

Nocardia infection develops when you breathe in (inhale) the bacteria. The infection causes pneumonia -like symptoms. The infection can spread to any part of the body.

People at highest risk for nocardia infection are those with a weakened immune system. This includes people who have:

• Been taking steroid medicines for a long time
• Had an organ transplant
• HIV

Other people at risk include those with chronic lung problems related to smoking, emphysema, or other infections such as tuberculosis.

Symptoms

• Entire body
  • Fever (comes and goes)
  • General ill feeling (malaise)
  • Night sweats, excessive sweating at night
• Gastrointestinal system
  • Nausea
  • Swollen liver and spleen (hepatosplenomegaly)
  • Unintentional weight loss
  • Vomiting
• Lungs and airways
  • Breathing gets harder and harder (pulmonary insufficiency)
  • Chest pain not due to heart problems
  • Coughing up blood
  • Cough with mucus
  • Rapid breathing
  • Shortness of breath
• Muscles and joints
  • Joint pain
• Nervous system
  • Change in mental state
  • Confusion
  • Dizziness
  • Headache
  • Seizures
• Skin
  • Skin rashes or lumps
  • Skin sores (abscesses)
  • Swollen lymph nodes

Signs and tests

• Bronchial alveolar lavage - fluid is sent for stain and culture
• Bronchoscopy
• Chest x-ray
• Crackles (rales) in the infected lung detected by stethoscope
• CT scan
• Decreased breath sounds in the lung
• Pleural fluid culture and stain
• Sputum stain and culture

Treatment

The goal of treatment is to control the infection. Antibiotics are used, but the response to treatment may be slow and you must keep taking the medications for at least 3 months. Patients who have medication allergies will need to take other antibiotics.

Surgery may be needed to remove or drain infected areas.

Expectations (prognosis)

The outcome is usually good with quick diagnosis and treatment. The outcome is poor when the infection spreads and treatment is delayed.

Complications

• Brain abscesses
• Diseased tissue (lesions) in the ribs
• Skin infections

Calling your health care provider

Call your health care provider if you have symptoms of this disorder. Early diagnosis and treatment may improve the chance of a good outcome.

Prevention

Be careful when using corticosteroids. Use these drugs sparingly, in the lowest effective doses and for the shortest periods of time possible.

Some patients with an impaired immune system may need to take antibiotics for long periods of time to prevent the infection from returning.

References

Southwick FS. Nocardiosis. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 351.