Sputum For Culture and Sensitivity

Function

Sputum Culture and Sensitivity is a laboratory test used to detect and identify bacteria or fungi that infect the lungs or airways. Sputum is the thick mucus (phlegm) produced by the lungs. The 'Sensitivity' portion of the test determines which specific antibiotics are most effective at killing the identified pathogen.

Why it is Ordered

This test is crucial for patients presenting with symptoms of deep respiratory tract infections, such as persistent cough, fever, chills, and shortness of breath. It is commonly used to diagnose bacterial pneumonia, lung abscesses, or exacerbations of chronic obstructive pulmonary disease (COPD).

Associated Conditions

• Bacterial Pneumonia: Caused by organisms like Streptococcus pneumoniae or Haemophilus influenzae.
• Tuberculosis (TB): Requires specific 'Acid-Fast Bacillus' staining and culture.
• Cystic Fibrosis: Patients often undergo routine sputum cultures to monitor for Pseudomonas colonization.
• Fungal Infections: Such as aspergillosis in immunocompromised individuals.

Procedure Note

A valid sample must come from deep within the lungs. Saliva is not sputum and will lead to inaccurate results. Laboratories often perform a 'Gram Stain' first to check if the sample contains enough white blood cells and few enough epithelial (mouth) cells to be considered high quality.