Sputum Gram stain

Gram stain of sputum

A sputum Gram stain is a laboratory test used to detect bacteria in a sputum sample. Sputum is the material that comes up from your air passages when you cough very deeply.

The Gram stain method is one of the most commonly used methods to rapidly identify the cause of a bacterial infection, including pneumonia.

Sputum test

A sputum sample is obtained by coughing deeply and expelling the material that comes from the lungs into a sterile cup. The sample is taken to a laboratory and placed in a medium under conditions that allow the organisms to grow. A positive culture may identify disease-producing organisms that may help diagnose bronchitis, tuberculosis, a lung abscess, or pneumonia.

How the Test is Performed

How to Prepare for the Test

How the Test will Feel

Why the Test is Performed

Normal Results

What Abnormal Results Mean

Risks