Pulmonary Nocardiosis: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Pulmonary Nocardiosis?
Care is most often led by an infectious disease doctor, who specializes in infections. Sometimes a pulmonologist, a lung specialist, helps too. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is pulmonary nocardiosis?
Pulmonary nocardiosis is a rare lung infection caused by bacteria called Nocardia. These bacteria are found in soil and water. People usually breathe the bacteria in through dust or droplets. The infection mostly affects people whose immune systems are weakened. It can be serious, but it is treatable with long courses of antibiotics.
Nocardia are germs that live in dirt, decaying plants, and standing water. When a person breathes them into the lungs, the germs can cause pneumonia. In some people, the infection can spread beyond the lungs to the brain, skin, or other organs.
Symptoms
Symptoms often come on slowly and can last for weeks. Common signs include a cough that may bring up mucus or pus, fever, chest pain, and feeling very tired. Some people also have night sweats, weight loss, or trouble breathing.
Causes and who gets it
The cause is breathing in Nocardia bacteria from soil, dust, or water. It is not spread from person to person. People at highest risk are those with weakened immune systems, such as people on transplant medicines, chemotherapy, or long-term steroids, or those with conditions like HIV or diabetes.
How doctors diagnose it
Doctors start with a medical history, an exam, and a chest X-ray or CT scan. To confirm the infection, they test samples of mucus or lung fluid in a lab to find Nocardia bacteria. If the infection may have spread, doctors might order extra tests, such as an MRI of the brain.
Treatment
Treatment uses antibiotics, often a medicine called trimethoprim-sulfamethoxazole. The course is long, usually lasting several months to a year or more. People with weakened immune systems may need to keep taking a lower dose afterward to prevent the infection from returning.
When to see a doctor
Anyone with a cough, fever, chest pain, or trouble breathing that lasts more than a few days should contact a doctor. People with weakened immune systems should seek care quickly when these symptoms appear. Seek urgent care for severe shortness of breath, coughing up blood, sudden confusion, or a very high fever.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either can be a helpful first stop. These doctors often have longer visits, which helps when a rare infection needs careful history taking and follow-up. They can order chest imaging and lab tests, start early treatment, and refer the patient to an infectious disease doctor or pulmonologist when needed.
Common questions
Is pulmonary nocardiosis contagious?
No. Nocardia does not spread from person to person. People catch it from the environment, usually by breathing in germs from soil or dust.
Can healthy people get it?
It is possible but uncommon. The infection mostly affects people whose immune systems are weakened. Healthy people who breathe in the bacteria usually clear them without getting sick.
How long does treatment last?
Treatment often lasts several months, and sometimes a year or more. The exact length depends on how severe the infection is and whether the person's immune system is weakened.
Does it come back after treatment?
It can return in some people, especially those with ongoing immune problems. Doctors use follow-up visits and sometimes repeat imaging to watch for this.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
