When should a specimen ideally be collected for diagnostic testing?
During the acute or early phase of illness.
What should be done if a specimen is collected after the initiation of antimicrobial therapy?
Use counteractive measures such as adding penicillinase or diluting the specimen.
Why are swabs generally considered poor specimens?
Swabs are prone to contamination and often do not collect enough material, except for nares and throat specimens.
Where should lesions, wounds, and abscesses be collected from for optimal results?
From the advancing margin of the lesion, preferably by aspiration.
What is an important transport guideline for specimens?
Specimens should be transported promptly or stored appropriately to prevent degradation of the suspected organism.
What type of specimen is unacceptable if used for anaerobic culture?
Specimens from sites known to have anaerobes as part of the normal flora, like the vagina or mouth
Why is a specimen received in fixative like formalin unacceptable for culture?
Formalin kills any microorganisms present, rendering the specimen unsuitable for culture.
What should be done with duplicate specimens from the same source and patient on the same day?
Only one specimen should be processed.
EXCEPT FOR BLOOD CULTURES
What makes expectorated sputum specimens unacceptable for culture?
If Gram stain reveals fewer than 25 white blood cells (WBCs) and more than 10 epithelial cells per low-power field (LPF) with mixed bacterial flora.
What is important to consider when selecting the anatomical site for specimen collection?
The correct anatomic site must be selected for specimen collection.
How should a specimen be collected to minimize contamination?
Using the proper technique and supplies with minimal contamination from normal biota.
Why is it important to collect an appropriate quantity of specimen?
To ensure enough material is available for testing.
When should a specimen be collected in relation to antimicrobial therapy?
Before the administration of any antimicrobial agent.
What should be considered when packaging a specimen for transport?
Package in a container or transport medium designed to maintain viability and avoid hazards.
What should be done when submitting swabs for direct smear and culture?
Submit two swabs: one for direct smear and one for culture.
What are some reasons a specimen might be rejected for testing?
Unidentified or improperly labeled specimens, information mismatch between the label and requisition, improper transport temperature, or not using the proper medium/container.
Why would a leaking specimen be rejected?
Leakage could compromise specimen integrity and safety.
What should be done if transport time exceeds 2 hours post-collection?
If the specimen is not preserved, it may be rejected for exceeding the acceptable transport time.
What happens to dry swabs submitted for culture?
They will be rejected since microorganisms may not survive on a dry swab.
Why should a specimen smeared on a slide not be submitted for culture?
This is not the proper specimen type for culture.
What is done with a specimen that would produce questionable medical value information (e.g., Foley catheter tip)?
It may be rejected for testing.
What should be done if a Gram stain of expectorated sputum reveals fewer than 25 WBCs and more than 10 epithelial cells per low-power field with mixed bacterial flora?
The specimen will be rejected for testing.
How long should specimens that are not processed immediately be refrigerated before discarding?
Specimens should be refrigerated for 3 days before being discarded.
In what type of containers should specimens be collected?
Sterile containers (except stool specimens).
Stool specimen - ok lang na di sterile as long as clean leak proof daw siya