Test Bank for Textbook of Diagnostic Microbiology 5th Edition by Mahon

Chapter 06: Specimen Collection and Processing

Test Bank

MULTIPLE CHOICE

Data generated by the laboratory is directly influenced by:

a.	the quality of the specimen and its condition when received.
b.	the physician’s decision to do the test.
c.	quality control is performed on a monthly basis.
d.	the air quality in the laboratory.

ANS: A

The old adage of garbage in–garbage out applies here. High-quality specimens result in high-quality laboratory results. Even though the laboratory professional does not usually perform the preanalytic process of collecting microbiology specimens, it directly affects the outcome.

REF: 112 OBJ: Level 1: Recall

To assist hospital personnel in collecting the highest quality specimen, the laboratory should:

a.	post the microbiology laboratory’s phone numbers in each section so personnel can call with questions and problems.
b.	develop a well-written handbook and make it available at every patient care unit.
c.	allow personnel to go to the floor and collect all specimens.
d.	severely reprimand staff for not collecting specimens properly.

ANS: B

The laboratory should establish policies for specimen management, and these must be distributed to all users and clients of microbiology laboratory services. A well-written handbook should be available at every patient care unit specifying the policies for specimen collection and transport, and test ordering. Training and education, such as in-services by the microbiology technologist, should be provided to the individuals collecting the specimens.

REF: 112 OBJ: Level 1: Recall

The goal of the specimen collector when collecting specimens for culture should be to:

a.	make sure the specimen gets to the laboratory.
b.	avoid hurting the patient when collecting the specimen.
c.	maintain the viability of the living organisms at the site with minimal contamination.
d.	get the specimen quickly to get the doctor off the collector’s back.

ANS: C

The specimens to be analyzed in the microbiology laboratory are likely to contain living organisms and the goal of the specimen collector must be to maintain the viability of these organisms with minimal contamination. That means the specimen needs to be delivered to the laboratory quickly so that the organisms do not die, taking your time when collecting the specimen to make sure you get a good one, and collecting the best specimen you can—even if it means inconveniencing the patient for just a little bit.

REF: 112 OBJ: Level 1: Recall

All the following principles of specimen collection are fundamental to ensuring appropriate specimen management except:

a.	collect the appropriate quantity of specimen.
b.	label the specimen accurately with the specific anatomic site and the patient information.
c.	select the correct anatomic site to collect the specimen.
d.	it is acceptable to delay transport of the specimen to the laboratory if it is in transport media.

ANS: D

The following principles of specimen collection are fundamental to ensuring appropriate specimen management: if possible, collect the specimen in the acute phase of the infection and before antibiotics are administered; select the correct anatomic site to collect the specimen; collect the specimen using the proper technique and supplies with minimal contamination from normal flora; collect the appropriate quantity of specimen; package the specimen in a container designed to maintain the viability of the organisms and avoid hazards due to leakage; label the specimen accurately with the specific anatomic site and the patient information; and transport the specimen to the laboratory promptly or make provisions to store the specimen in an environment that will not degrade the suspected organism(s).

REF: 112 OBJ: Level 1: Recall

Why does a fecal sample for culture need to be collected in a leak-proof, nonsterile container?

a.	Fecal samples can be runny and if the specimen leaks, this can present a biohazard.
b.	Many types of bacteria call the intestinal tract home; the specimen cannot become contaminated.
c.	Leak-proof containers are always sterile, so the container will be leak-proof, as well as sterile.
d.	Because DNA probes can determine resident flora from pathogenic bacteria.

ANS: B

There are many types of bacteria in a normal, healthy colon. With so many bacteria as normal flora, the risk of contamination is slight with a stool specimen. Stool specimens are evaluated for specific pathogens rather than identifying all bacteria present.

REF: 112 OBJ: Level 2: Interpretation

Swabs are appropriate for specimens collected from all the following sites except:

a.	upper respiratory tract.
b.	external ear.
c.	urine.
d.	genital tract.

ANS: C

In general, swabs are not recommended for urine collection because they do not provide sufficient quantity, are easily contaminated, and can become dried out, leading to a loss of organisms. Swabs are appropriate for specimens from the upper respiratory tract, external ear, eye, and genital tract. Swab collection systems are available that provide transport media and protect the specimen from drying. Urine cultures are always spread on a plate using a calibrated loop so that the technician can estimate the number of organisms present in the urine specimen.

REF: 112 OBJ: Level 2: Interpretation

How should specimen collection instructions be given to the patient to ensure collection of a good specimen for culture?

a.	Verbally
b.	Verbally, in many different languages
c.	Verbally and written in English
d.	Written, using simple language (in several languages) and pictures to help the patient understand the procedure as it is verbally explained

ANS: D

It is best to give the patient as much information as possible to collect the specimen. It is always good to read the procedure to the patient and show pictures to ensure they understand the procedure. This needs to be done in more than one language, because sometimes the patient does not speak English well and may not understand the procedure.

REF: 112 OBJ: Level 1: Recall

Why is a clean-catch midstream urine used for a urine culture as opposed to a clean-catch urine?

a.	The first portion of the urine flow washes contaminants from the urethra and the next portion of urine is more representative of the bladder.
b.	The name was changed, but the procedure remains the same and the entire amount of urine from the bladder is cultured.
c.	No urine is free from contamination, so just wipe the external genitalia and void into the cup.
d.	Catheterized specimens are also called clean-catch midstream urine specimen.

ANS: A

Instructions for urine collection must include an explanation of the clean-catch midstream urine specimen. A first-morning specimen is preferred because it provides a more concentrated sample. The patient collects this specimen following cleansing of external genitalia to reduce the presence of indigenous flora. Patients are asked to void without collecting the first portion of the urine and instead to collect the middle portion. The first portion of the urine flow washes contaminants from the urethra and the midstream portion is more representative of the bladder. Personnel collecting catheterized specimens should also use this technique to eliminate organisms carried up the urethra during catheterization.

REF: 114 OBJ: Level 2: Interpretation

Sputum specimens are often collected for the diagnosis of:

a.	acute pharyngitis.
b.	bacterial pneumonia.
c.	meningitis.
d.	diverticulitis.

ANS: B

Many types of bacterial pneumonia produce purulent material that is coughed up as sputum. This specimen may contain the pathologic agents producing the disease. Unfortunately, lower respiratory tract specimens are among the most difficult specimens to collect adequately because they are contaminated with oropharyngeal flora.

REF: 114 OBJ: Level 2: Interpretation

The best way to minimize the amount of upper respiratory flora in a sputum specimen is to follow which of these procedures?

a.	Cough up the specimen and when the specimen gets to the laboratory, digest it with enzymes that will kill the normal flora.
b.	When plating the specimen, ensure that the swab goes deep into the sample to get only bacteria present in the lower lung.
c.	Have the patient rinse the mouth with water and expectorate with the aid of a really deep cough directly into a sterile container.
d.	Have a respiratory technician decontaminate a patient’s mouth and throat before the specimen is collected.

ANS: C

Rinsing the mouth will clean out most of the normal flora. A deep cough should gather as much purulent material as possible from the lower lung area. Using enzymes to digest the specimen will kill all bacteria in it, not just the normal flora. Sometimes the sputum is so thick that it is not possible to probe into the middle of the specimen to avoid any outer contaminating flora. It is not practical to have a respiratory technician disinfect a patient’s mouth and throat before collecting a sputum specimen.

REF: 114 OBJ: Level 2: Interpretation