In case of delay in transportation of cerebrospinal fluid (CSF) sample, it should be?

BHU NO - 2015

Applied Microbiology & Infection control

Hard

Appeared in: BHU NO - 2015

Explanation

CSF samples for bacterial culture must be transported and processed immediately to ensure the viability of pathogens.
If a delay is unavoidable, the sample must be kept at room temperature (20-25°C) or incubated at 37°C.
This procedure is critical to prevent the death of fastidious (delicate) bacteria, such as Neisseria meningitidis and Haemophilus influenzae, which are common causes of meningitis and are highly sensitive to cold temperatures.

Option B: Refrigeration at 4°C is incorrect because this temperature can kill or inhibit the growth of sensitive pathogens like Neisseria meningitidis, leading to a false-negative culture result.
Option C: Freezing at -20°C would destroy the cellular structure of any bacteria present, making it impossible to culture and identify them.
Option D: Placing the sample in an ice bucket has the same detrimental effect as refrigeration. The cold temperature would harm or kill the very bacteria the test aims to detect.

Clinical Relevance

Nursing practice connection: Knowing Proper handling and transport of cerebrospinal fluid (CSF) samples for microbiological analysis helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
The correct handling of a CSF sample is directly linked to the ability to diagnose bacterial meningitis, a medical emergency. A false-negative result due to improper storage can lead to delayed treatment, resulting in severe neurological damage or death.
Nurses are often responsible for ensuring specimens are collected and transported correctly. Knowing this rule is a critical patient safety measure.
What if the CSF sample was for viral PCR testing instead of bacterial culture? In that case, refrigeration at 4°C or freezing would be acceptable, as the test detects viral genetic material, not live organisms.

How to Approach the Question

First, identify the type of specimen: Cerebrospinal Fluid (CSF).
Next, understand the implied purpose. A question about CSF transport delay often relates to diagnosing meningitis, which requires a bacterial culture.
Recall the characteristics of common meningitis-causing bacteria. Many, like Neisseria meningitidis, are 'fastidious,' meaning they are delicate and require specific conditions to survive.
Consider how temperature affects these delicate bacteria. Cold temperatures are lethal to them.
Evaluate the options based on this knowledge. Eliminate refrigeration, freezing, and ice, as they would compromise the sample's integrity for bacterial culture.
Conclude that keeping the sample at room temperature is the only option that preserves the viability of these sensitive organisms.

Concept Tested & Keywords

Concept Tested: Proper handling and transport of cerebrospinal fluid (CSF) samples for microbiological analysis.
Stem keywords: delay, transportation, cerebrospinal fluid (CSF) sample
Lead-in keywords: should be

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