A sputum Gram stain is a laboratory test that uses a series of stains to check for bacteria in a sputum sample. Sputum is the mucous material that comes up from your air passages when you cough very deeply.
The Gram stain method is one of the most commonly used techniques for the rapid diagnosis of bacterial infections, including bacterial pneumonia.
Alternative NamesGram stain of sputum
How the test is performedA sputum sample is needed. You will be asked to cough deeply and spit any material that comes up from your lung into a special container. If this does not work, you may receive a breathing treatment before the test to help you produce the sample. If you have a dry cough or are unable to produce a sample, a bronchoscopy may be necessary.
The sample is sent to a lab. The lab team member places a very thin layer of the sample onto a glass slide -- this is called a smear. A series of special stains is applied to the sample. The lab team member looks at the stained slide under a microscope, checking for bacteria and white blood cells. The color, size, and shape of the cells help identify the infecting organism.
How to prepare for the testNo preparation is usually needed, unless a bronchoscopy is necessary.
How the test will feelHow the test will feel depends on the method used to produce the sample. More discomfort is associated with a bronchoscopy.
Why the test is performedYour doctor may order this test if you have a persistent or prolonged cough, or if you are coughing up material that has a foul odor or unusual color. The test may also be done if you have other signs and symptoms of respiratory disease or infection.
Normal ValuesA normal result means that few to no white blood cells and no bacteria were seen in the sample. The sputum is clear, thin, and odorless.
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
What abnormal results meanAn abnormal results means that infection-causing organisms are present in the sample. This is a sign that a bacterial infection may be present. A sputum culture is needed to confirm the diagnosis.
What the risks areThere are no risks associated with coughing up a sample. See the article on bronchoscopy for information regarding risks related to that procedure.
Special considerationsThe test may need to be repeated if the sample contains only saliva from the mouth.
ReferencesMandell LA. Pneumococcal pneumonia. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 311.
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 detect a bacterial infection, including pneumonia.
Alternative NamesGram stain of sputum
How the test is performedA sputum sample is needed. You will be asked to cough deeply and spit any material that comes up from your lung into a special container.
The sample is sent to a lab. The lab team member places a very thin layer of the sample onto a glass slide. This is called a smear. Stains are placed on the sample. The lab team member looks at the stained slide under a microscope, checking for bacteria and white blood cells. The color, size, and shape of the cells help identify the bacteria.
How to prepare for the testNo preparation is usually needed, unless a bronchoscopy is necessary.
How the test will feelHow the test will feel depends on the method used to produce the sample. More discomfort is associated with a bronchoscopy.
Why the test is performedYour doctor may order this test if you have a persistent or prolonged cough, or if you are coughing up material that has a foul odor or unusual color. The test may also be done if you have other signs and symptoms of respiratory disease or infection.
Normal ValuesA normal result means that few to no white blood cells and no bacteria were seen in the sample. The sputum is clear, thin, and odorless.
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
What abnormal results meanAn abnormal results means that bacteria is seen in the test sample. You may have a bacterial infection. A culture is needed to confirm the diagnosis.
What the risks areThere are no risks associated with coughing up a sample. See the article on bronchoscopy for information regarding risks related to that procedure.
Special considerationsThe test may need to be repeated if the sample contains only saliva from the mouth.
ReferencesLimper AH. Overview of pneumonia. In: Goldman L, Schafer AI, eds.Cecil Medicine. 24th ed.Philadelphia,PA: Saunders Elsevier; 2011:chap 280.
Reviewed ByReview Date: 12/06/2011
Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
YES
.the sputum must be collected into a sterile container. Once in the laboratory, each culture type is handled differently. Bacterial culture.sputum is smeared on a microscope slide for a Gram stain. for mold or yeast, a fungal culture is done.
A gram stain is a cow
The gram stain uses a decolorizing product so it is possible to differentiate between the gram and the gram cells. Gram positive cells stain purple in color.
Gram stain
Gram Negative
Protists are often stained using a silver stain, not a Gram stain.
The Gram stain is used for bacteria and not for viruses.
Bacteria stain either gram-positive or gram-negative based on the presence or absence of a cell wall. Viruses do not pick up a gram stain.
Hans Christian Gram invented this stain in 1884
gram -
Bacteria stain either gram-positive or gram-negative based on the presence or absence of a cell wall. Viruses do not pick up a gram stain.