Urobilinogen Testing Methods

What is the primary reaction used in Multistix for urobilinogen testing?

What color variation indicates the presence of urobilinogen in Multistix testing?

What substances can be detected by the Ehrlich reagent aside from urobilinogen?

How is urobilinogen detected using the Chemstrip method?

What is the normal range for urobilinogen values in deciliters according to Multistix testing?

What is a limitation of the multistix method for detecting porphobilinogen?

What is the primary indicator of urobilinogen presence in the Chemstrip test?

What is the detection limit for urobilinogen in the Chemstrip test?

Which of the following methods primarily relies on the formation of an azo dye?

What compound is used in Multistix testing to produce a reddish brown color?

Reagent Strip Methods for Urobilinogen Testing

Principle: Urobilinogen testing relies on either the Ehrlich aldehyde reaction or a diazonium compound reaction to form a colored product.
Multistix Method: Multistix uses the Ehrlich aldehyde reaction. Its test area contains an acid buffer and p-dimethylaminobenzaldehyde. Urobilinogen reacts with this reagent, producing a reddish-brown color. Normal values range from 0.2 to 1 mg/dL.
Color Interpretation: Color varies from light yellow to shades of red-brown.
Limitations: The Multistix method isn't specific to urobilinogen. It detects substances that react with the Ehrlich reagent, including porphobilinogen, certain drug metabolites (e.g., p-aminosalicylic acid, sulfonamides), procaine, 5-hydroxyindoleacetic acid, indole, and methyldopa. This method is unreliable for detecting porphobilinogen.
Chemstrip Method: Chemstrip uses a diazonium compound (4-methoxybenzene-diazonium-tetrafluoroborate) to detect urobilinogen. This compound reacts with urobilinogen in an acidic environment to form a red azo dye.
Chemstrip Results: Results are read quickly (10-30 seconds). The test detects approximately 0.4 mg/dL of urobilinogen.

This quiz covers the principles and methodologies used in urobilinogen testing, including the Multistix and Chemstrip methods. It discusses the reactions involved, color interpretations, and limitations of each method. Test your knowledge on these important diagnostic techniques.