In what clinical situation would a direct smear report from the laboratory be of urgent importance?
David Craig 
The physician would order for direct smear test from the patient sample in situations are require immediate medication. In conditions like severe or contagious infections such as tuberculosis, the physician would need to start medication immediately in order to save lives.
What is a differential stain name two examples?
Flagella Staining
| Table 3. Differential Stains | |
|---|---|
| Stain Type | Specific Dyes |
| Gram stain | Uses crystal violet, Gram’s iodine, ethanol (decolorizer), and safranin |
| Acid-fast stain | After staining with basic fuchsin, acid-fast bacteria resist decolonization by acid-alcohol. Non-acid-fast bacteria are counterstained with methylene blue. |
What might cause a gram-negative to be seen as a gram positive?
If the decolorizing agent is applied on the cell for too long time, the Gram-positive organisms to appear Gram-negative. Under-decolorization occurs when the alcohol is not left on long enough to wash out the CV-I complex from the Gram-negative cells, resulting in Gram-negative bacteria to appear Gram-positive.
What is the current theory about the mechanism of the Gram stain reaction?
What is the current theory about the mechanism of the Gram-stain reaction? Gram positive, which retains crystal violet dye, is thought to be composed of peptidoglycans which traps the crystal violet dye. Gram negative walls are high in lipids which dissolves the decolorizer and turns a pinkish-red.
What is the purpose of the iodine step?
The next step, also known as fixing the dye, involves using iodine to form crystal violet- iodine complex to prevent easy removal of dye. Subsequently, a decolorizer, often solvent of ethanol and acetone, is used to remove the dye.
Is E coli Gram positive or negative?
Escherichia coli (E. coli) is a Gram-negative, rod-shaped, facultative anaerobic bacterium. This microorganism was first described by Theodor Escherich in 1885.
What are the three types of stains?
Stains can be classified into the following types, depending upon its chemical nature and the type of staining methods. Based on chemical nature: There are three kinds of stain, acidic, basic and neutral, depending upon the chemical nature of the stain. Based on the staining method: There are four kinds of stain, viz.
How many types of stains are there?
Seven Types of Stain. We use the term “stain” to identify a colorant we apply to wood to change its color. But stains are not equal. Besides the obvious differences in color, there are at least seven categories of commercial stains that each apply and color differently.
What infections are caused by Gram negative bacteria?
Gram-negative bacteria cause infections including pneumonia, bloodstream infections, wound or surgical site infections, and meningitis in healthcare settings. Gram-negative bacteria are resistant to multiple drugs and are increasingly resistant to most available antibiotics.
What color is Gram negative bacteria?
Red
Gram negative organisms are Red. Hint; Keep your P’s together; Purple is Positive. Gram stains are never pink they are red or purple so you don’t destroy the rule; keep your P’s together. In microbiology bacteria have been grouped based on their shape and Gram stain reaction.
