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Overview

What Is Nocardiosis?

Nocardiosis is an uncommon bacterial infection caused by bacteria called Nocardia. The bacteria can enter the body when a person breathes in contaminated soil or dust, or when they enter an open wound in the skin. Infection often begins in the lungs or skin, but it can spread to the brain or other organs. People with weakened immune systems have a higher risk of serious nocardiosis disease.

Symptoms

Symptoms of Nocardiosis

Symptoms affecting the lungs

  • Cough that may persist or worsen
  • Fever
  • Chest pain
  • Shortness of breath
  • Coughing up blood (hemoptysis)

Skin, brain, and widespread symptoms

  • Redness or swelling around a skin infection
  • Painful or draining skin lesions (cutaneous nocardiosis)
  • A skin abscess
  • Headache from brain involvement
  • Confusion
  • Seizures
  • Weakness in an arm or leg
  • Fever or symptoms involving several organs (disseminated nocardiosis)

How It Spreads

How Nocardiosis Spreads

Nocardia bacteria live in soil, dust, and decaying organic matter. They may enter the body when contaminated particles are inhaled into the lungs or when bacteria enter through a cut, scrape, or other open wound. This environmental exposure can lead to pulmonary infection or cutaneous nocardiosis, particularly when immune defenses are reduced.

Risk Factors

Risk Factors for Nocardiosis

  • An organ transplant or stem-cell transplant can require medicines that weaken immune defenses.
  • HIV infection, especially when untreated or advanced, increases the risk of infection.
  • Cancer and some cancer treatments can reduce the body’s ability to fight Nocardia bacteria.
  • Chronic lung disease may make pulmonary infection more likely.
  • Other immune-system disorders can increase the risk of nocardiosis and disseminated nocardiosis.

Treatment-related and environmental factors

  • Long-term corticosteroid or other immunosuppressive medicine use can lower immune protection; do not stop prescribed medicine without medical advice.
  • A prolonged hospitalization may be relevant when severe illness or immune suppression is present.
  • Frequent work or outdoor activity involving soil, dust, or decaying plant material can increase exposure.
  • Open cuts or wounds that contact contaminated soil may allow Nocardia bacteria to enter the skin.
  • People with ongoing immune suppression should ask their clinician about individualized exposure precautions.

Complications

Complications of Nocardiosis

  • A brain abscess or another central nervous system infection
  • Respiratory failure from severe lung infection
  • Infection involving multiple organs (disseminated nocardiosis)
  • Persistent skin damage or scarring
  • Relapse after treatment
  • Death in severe or untreated cases

Serious complications

When infection spreads

Nocardiosis can spread beyond the first affected site, including to the brain, bloodstream, or other organs. Prompt treatment is especially important for people with weakened immunity and anyone who develops new neurologic symptoms.

Diagnosis

Diagnosis of Nocardiosis

Diagnosing nocardiosis requires laboratory identification of Nocardia from a suitable specimen. Symptoms can resemble other bacterial or fungal infections, so clinicians consider the person’s immune status, symptoms, exposure history, and test results when making the diagnosis.

  • A sputum sample or respiratory culture may identify Nocardia in people with lung symptoms.
  • A wound or skin sample can be tested when a lesion or abscess is present.
  • Blood cultures may be collected when bloodstream or widespread infection is suspected.
  • Brain or other organ imaging can show abscesses or areas affected by disseminated infection.
  • Antibiotic susceptibility testing helps guide the most effective medicine.

Treatment & Management

Nocardiosis Treatment and Management

Nocardiosis is treated with prescription antibiotics, often for many months. The specific medicine is chosen according to the Nocardia species, antibiotic susceptibility results, infection site, severity, immune status, and other patient factors. Regular follow-up helps clinicians assess the response and adjust treatment when needed.

Management by infection site and severity

  • Localized skin or lung infection is treated with a susceptibility-guided antibiotic plan.
  • Severe or disseminated nocardiosis may require combination antibiotic therapy and close monitoring.
  • An abscess may need drainage or surgery in addition to antibiotics.
  • Clinicians treat underlying immune problems and review medicines that may affect immune defenses.
  • Supportive care may be needed when lung, brain, or other organ function is affected.

Treatment safety

Follow the treatment plan

Complete the prescribed antibiotic course and attend follow-up visits and testing, even if symptoms improve. Report medication reactions promptly rather than stopping treatment independently.

Prevention

Can Nocardiosis Be Prevented?

  • Wear gloves and protective clothing when working with soil, dust, or decaying organic material.
  • Cover open wounds before outdoor work or contact with soil.
  • Clean cuts and scrapes promptly with soap and water.
  • Follow the care plan for conditions or medicines that weaken the immune system.
  • Ask a clinician about personalized precautions if you have significant immune suppression.

Outlook and Prognosis

Outlook and Prognosis for Nocardiosis

Many cases of nocardiosis can be treated successfully when recognized early and treated with the right antibiotics. The outlook is less favorable when infection has spread, involves the brain, causes severe lung disease, or occurs after a delayed diagnosis. Significant immune suppression can also make recovery more difficult.

  • The organs affected and the extent of spread influence the outlook.
  • The Nocardia species and its antibiotic susceptibility affect treatment choices and response.
  • Immune function can influence how well the body controls the infection.
  • The response to treatment helps clinicians assess recovery.
  • Completing prolonged antibiotic therapy improves the chance of controlling infection.

When Should You See a Doctor

When Should You See a Doctor?

Seek medical care

Do not ignore persistent or worsening symptoms

Arrange prompt medical evaluation for a persistent cough, fever, shortness of breath, worsening skin lesions, or unexplained symptoms, especially if you have a weakened immune system. Early assessment can help identify lung, skin, brain, or widespread infection.

  • Severe trouble breathing
  • Coughing up blood
  • Confusion
  • A seizure
  • New weakness
  • A severe headache
  • Rapidly worsening illness

Branches

2 topics

Symptoms

1 topic

  • Nocardiosis

    Fever