Guaiac test is used for?

RUHS, Jaipur, M.Sc Nursing Entrance Exam-2021

Nursing Foundation

Easy

Appeared in: RUHS, Jaipur, M.Sc Nursing Entrance Exam-2021

Explanation

The Guaiac test is a type of Fecal Occult Blood Test (FOBT) used to screen for hidden (occult) blood in the stool.
It works by detecting the peroxidase-like activity of hemoglobin, a component of red blood cells.
When a developer solution is applied to a stool sample on a guaiac-impregnated card, a blue color change indicates the presence of hemoglobin, signifying a positive result for occult blood.
This test is a common, non-invasive screening method for conditions that cause gastrointestinal bleeding, most notably colorectal cancer and polyps.

Option A: Pentosuria is a condition where the sugar pentose is excreted in the urine. It is a disorder of carbohydrate metabolism and is detected through urinalysis, not a stool test.
Option B: Fructosuria is a condition involving the presence of fructose in the urine. Like pentosuria, it is a metabolic disorder diagnosed via urinalysis.
Option C: Pancreatitis is the inflammation of the pancreas. The primary diagnostic markers are elevated levels of serum amylase and lipase, which are enzymes measured in a blood test.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Diagnostic use of the Guaiac test as background academic context rather than a clinical decision trigger.
Nurses are responsible for providing clear instructions to patients on how to collect the stool sample and what dietary and medication restrictions to follow to ensure the accuracy of the Guaiac test.
A positive Guaiac test is a critical finding that requires prompt reporting and scheduling of follow-up diagnostic procedures, such as a colonoscopy, to determine the source of bleeding.
Patient education is key to reducing anxiety; nurses should explain that a positive result is not a diagnosis of cancer but an indication that further investigation is needed.

How to Approach the Question

First, identify the key term in the question, which is 'Guaiac test'. Recognize this as a specific diagnostic procedure.
This is a factual recall question. Access your knowledge about common laboratory and diagnostic tests.
Analyze the options. Note that 'Pentosuria' and 'Fructosuria' end in '-uria', strongly suggesting they are related to urine, not stool.
Consider 'Pancreatitis'. Recall that this organ's function is typically assessed with blood tests for specific enzymes like amylase and lipase.
This leaves 'Occult blood in stool'. The Guaiac test is the classic, most well-known chemical test for this exact purpose, primarily for colorectal cancer screening.
Confirm the match between the test and its primary application to select the correct answer.

Concept Tested & Keywords

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