collection of laboratory specimens

1. COLLECTION, TRANSPORTATION, PREPARATION,
PROCESSING, AND STORAGE OF LABORATORY SAMPLES
FOR THE DIAGNOSIS AND MONITORING OF DISEASES
A SEMINAR PREPARED
BY
LAWAL, BELLO DANCHADI
ADM NO: 22210705001
DEPARTMENT OF CHEMICAL PATHOLOGY AND
IMMUNOLOGY
USMANU DANFODIYO UNIVERSITY, SOKOTO

2. Introduction
Sample
• International Standard Organization (ISO) define a sample as “one or more parts taken from a
system and intended to provide information on the system” (ISO 15189:2007).
Specimen
• The term “specimen” is very commonly used in the laboratory to indicate a small quantity
substance taken from the human body for clinical analysis or examinations, but the terminology
used throughout ISO documents is “primary sample”, or just “sample”. In this workshop, the
terms “sample” and “specimen” should be considered interchangeable.
Examples of laboratory samples
• Blood • Semen. • Gastric juice
• Urine • Feces • Sweat
• Saliva • Pleural fluids • Synovial fluid
• CSF and many other body fluids

3. Collection of specimens
 Is the process or act designed in receiving specimens for laboratory analysis, (Campbell J.D. et al.,
2008)
 The clinical state of the patient will not necessarily be reflected by the result of laboratory
investigation despite correct laboratory performance unless the specimen is in optimal condition
required for the analysis.
 Some of the important specimens and their proper collection and transportation methods are
described here so as to ensure quality.

4. Sample collection requirements
• patient preparation • Patient identification • Type of sample required
• Type of Container • Sample labeling • Special handling
Potential outcomes of collection errors
Proper sample collection is an important element for good laboratory practice.
Improper collection of samples can lead to poor outcomes, such as:
• Delays in reporting test results • Unnecessary re-draws/re-tests
• Decreased customer satisfaction • Increased costs
• Incorrect diagnosis / treatment • Injury • Death.
Objectives of samples collection
• Research purposes, • Diagnosis diseases,
• Treatment and management of diseases,

5. The Right Collection & Transportation of specimens
 Apply strict aseptic techniques throughout the procedure.
 Wash hands before and after the collection.
 Collect the specimen at the appropriate phase of disease.
 Make certain that the specimen is representative of the infectious process (e.g. sputum is the specimen for
pneumonia and not saliva) and is adequate in quantity for the desired tests to be performed.
 Collect or place the specimen aseptically in a sterile and/or appropriate container.
 Ensure that the outside of the specimen container is clean and uncontaminated.
 Close the container tightly so that its contents do not leak during transportation.
 Label and date the container appropriately and complete the requisition form.
 Arrange for immediate transportation of the specimen to the laboratory.

6. BLOOD collection method
• Blood collection, usually involves the removal of
blood and it comes in many different forms.
• It's also a common term in blood sampling for
laboratory analysis.
Three popular methods of blood collection are:
• 1. Arterial Sampling
• 2. Venipuncture Sampling
• 3. Finger stick Sampling
METHODS OF SAMPLE COLLECTION

7. ARTERIAL SAMPLING
 This form of blood collection most commonly takes place within a hospital
environment.
 It is used in the identification of metabolic, respiratory, and mixed acid-base
disorders, where CO2 levels require understanding or monitoring.
 While generally safe, the procedure can be upsetting and painful for the patient.
 There are also several potential contradictions that can affect the site of the
collection, such as an abnormal modified Allen test or local infection.
 There is also an increased risk of bleeding complications in patients with
coagulopathy

8. 2. VENIPUNCTURE SAMPLING
• Venipuncture is the most common way to collect blood from adult patients.
• Collection takes place from a superficial vein in the upper limb, generally the
median cubutal vein; this vein is close to the skin and doesn’t have many
large nerves positioned close by.
• This reduces pain and discomfort for the patient.
• Clean the sight with spirit allow to dry. Readily attached syring and needle is
introduced to the vein with the level facing upward at an angle of 30° – 40°.
• Entrance into the vein is denoted by appearance ofblood into the hub of the
needle.
• Release the tourniquet an withdrawn the needle. The blood is transfer into the
appropriate containers.

9. 3. FINGER STICK SAMPLING
 Fingerstick or finger prick sampling involves taking a very small amount of
blood from the patient, usually from the ball of a finger.
 It is also known as capillary blood collection.
 It is quickly and requires in little amount; therefore, reducing concern and
anxiety in patients, particularly in children and nervous adults.
 Clean the finger with alcohol swab and allow to dry.
 Hold the ball finger and make a quick puncture about ½ cm from the end using a
sterile lancet, wipe the first drop as it may contains tisuue fluids.
 The blood should flow freely, without applying pressure collect the
succeeding drop for investigation.
 It is mainly used for doing differential count, cell count, Hb estimation, etc…

10.  Before or after the sample collection, the tube should be labelled
immediately.
 Requiring patients to state their full name and birth date, and to spell their
first name and last name;
 Requiring outpatients to show a form of identification when an ID band is
not in use, typically a driver’s license or insurance card;
 Labeling specimen tubes in the presence of the patient after the draw,
 Visually comparing tube labels with the ID band or requiring the patient to
confirm samples are properly labeled.
 It should be help avoid errors.
LABELING

11. TYPES OF BLOOD COLLECTION TUBES
Red :
 No anticoagulant or additives.
 Collection of serum for chemical or serological and bacteriologic studies.
 Maybe used for any procedure requiring serum except HLA antibody tests.
Lavender :
 Contains EDTA (Ethylene Diamine Tetra Acetate) as the anticoagulant.
 Mix well Primarily for collection of hematology studies, blood bank procedures and certain chemistries.
Blue :
 Contains sodium citrate (0.109M, 3.2%) solution as the anticoagulant.
 Primarily for collection of coagulation studies.
Gray :
 Contains potassium oxalate and sodium fluoride as the anticoagulant.
 Mix well For the collection of glucose and lactate samples.
 Not suitable for enzymes or electrolytes.

12. Green :
 Contains lithium heparin as the anticoagulant.
 Mix well For collection of other miscellaneous studies.
 Electrolytes, glucose, BUN can be performed more quickly than from a red top.
Special green :
 Sterile, contains sodium heparin as the anticoagulant.
 For collection of flow cytometry specimens.
Yellow :
 contains ACD (Acid Citrate Dextrose) as the anticoagulant.
 For determination of HLA-ABC antigens, HLA-B27, HLA Molecular Typing, G6PD levels and
acid phosphatase levels.
Pink :
 Does not contain any anticoagulant, serum separator, or silicone coating.
 For detection of HLA antibodies in serum.

13. Seperation and Storage of Serum/Plasma
• Plasma: A virtually cell-free supernatant of blood containing anticoagulant (heparin, EDTA, Fluoride oxalate,
Sodium citrate, etc) obtained after centrifugation at 2000g to 3000g for 15mins, contains clotting factors and
store at -4°C.
• Serum: The undiluted, extracellular portion of blood after adequate coagulation is complete or centrifuge at
1500g for 10mins, contains no clotting factors.
• Serum or plasma should be separated from red blood cells as soon as possible, a maximum
• limit of two hours from the time of collection is recommended. A contact time of less than two hours is
recommended for Glucose, potassium, Viral load, ACTH, cortisol, catecholamine, lactic acid and
homocysteine.
• Non-centrifuged samples should be stored at room temperature for the time specified in the recommendations
for stability.
• After centrifugation, the serum or plasma should be analyzed within the time as recommended for whole blood.
• When the sample shall be refrigerated at or frozen for preservation, blood cells must first be separated from
serum or plasma.

14. URINE SAMPLE COLLECTION METHOD
What is urine ?
 Urine is an ultrafiltrate ofthe blood plasma and fluid created in the kidney and stored in the urinary
bladder.
 It is a waste product and it can give us a wealth of information! Many metabolic diseases can be
detected and monitored via the urine.
 Urine is mostly water with dissolved metabolites.
Urine Specimen Types Include:
1. First/Early Morning Urine:
• The first urine is voided when waking up after sleep, since it has been retained and incubating in the
bladder for 6-8 hours and is the most concentrated specimen
 Ideal for testing for protein or to confirm postural or orthostatic proteinuria
 Ideal for testing for nitrites.
 Red blood cells, white blood cells, and casts that maybe present will be more stable.
 The urine is slightly more acidic and has high osmolality during the night, before the
individual should void before going to bed.

15. 2. Random Urine Specimen:
 This type of urine specimen can be collected at anytime, whether day or night
 No prior patient preparation
 Easy and convenient
 Good for routine screening
 Good for cytology studies
 Good for fluid deprivation studies
 “Random clean catch" type of specimens can also be performed after good hydration and
are perfect for cytology studies
 Individual will consume 24-32 oz of water each hour for 2 hours prior to urine collection
may require collection daily for 3-5 consecutive days
 Enhanced by patient exercise for 5 minutes prior to specimen collection (jumping,
skipping, running in place)

16. 3. Timed Collection:
 This specimen is collected throughout a very specific time interval (ex: 2 hours, 12 hours, 24 hours,
over a weekend, etc...)
 Avoid at the beginning ofthe collection then discard it
 Collect all subsequent urine
 Include the last void in the urine
4. Catheterized Urine:
 Obtained using a sterile, flexible tube catheter, which is inserted into the urethra and into the bladder
 Urine flows into the bladder by gravity and is collected in a plastic reservoir bag
 Requires healthcare personnel to perform
 UTIs are common in catheterized patients, so these are often sent for bacterial culture

17. Catheterized Urine sample collection

18. 5. Routine Void:
 Does not require patient preparation
 Simple urination into a specimen collection container
6. Midstream "Clean Catch:
 Urine is collected after thorough cleansing of the urethral opening with antiseptic wipes
 The individual must pass the first portion ofthe urine in the toilet, stop the stream, then collect the mid portion
of the urine into the specimen container, followed bypassing remaining urine into the toilet
 Ideal for the routine urinalysis and urine culture free from contamination
7. Suprapubic Aspiration:
A rare technique used to collect urine directly form the bladder via the puncturing of the abdominal wall and
distended bladder following the use of a sterile needle and syringe
This technique is used to obtain sterile urine for bacterial cultures from infants or adults, is aspirated into the
syringe, capped and sent for analysis

19. 9. URINE SAMPLE COLLECTION
 The urine specimen containers for collection should be clean, dry, sterile, made of clear translucent,
disposable plastic or glass.
 It should be stable and able to stand upright, with a rim of 4-5 cm.
 It should be able to hold as much as 50-0100 mL ofurine.
 It should also come with the lid tightly screwed on and should be a leak proof seal or covered to prevent
leaks or spills.
 Always wear gloves and proper PPE when working with urine.
8. Pediatric Collections:
 Sterile, plastic urine collection bags with a hypoallergenic skin adhesive are used for collection
after the perineal area is cleaned and dried prior to placement ofthe specimen bag onto the
skin
 The patient is checked every 15 minutes to see if enough specimen has been collected

20. LABELING
 Before the sample collection the container should be labelled immediately.
 Requiring patients to state their full name and birth date, and to spell their first name and
last name.
 It should be help avoid errors.
 The labels should contain adhesive that resists moisture and will stick during refrigeration.
It should contain the
• Patient's full name
• A unique ID number
• The date and time of collection
• An ID or information about the room number or clinic name of
collection
• The type ofpreservative used and date/time.

21. Urine Storage and Handling :
 Ideally, once collected, urine specimens should be sent immediately to the laboratory.
 Time of arrival to the laboratory should be documented.
 If this is not possible, the specimen should be preserved or refrigerated.
 Transportation to the laboratory or some type ofpreservation must occur within 2 hours of
collection, otherwise the specimen will be no good and will need to be rejected.
 Urine is sensitive to light, temperature, moisture, and microbes in the environment.
Urine preservation method
 Urine preservative is basically either a chemical substance or a processor technique used to
prevent changes in the composition of the urine until it can be tested, or to prevent deterioration
of any formed elements.
 The most common form ofurine preservation is refrigeration, though there are chemical means to
preserve urine for a couple ofhours at room temperature as well.

22.  First or early morning urine specimens have high osmolality, and are therefore prone to salts
crystallizing upon cooling to room temperature, which are known as amorphous urates, which
can interfere with some cytological studies.
 Random urine specimens maybe preferred for this type of testing.
 Specimens need to be preserved within 2 hours of collection if not analyzed immediately.
 Changes in unpreserved urine maybe
A) Physical - Color, Clarity , Odour
B) Chemical - pH, Glucose, Ketones Bilirubin, Urobilinogen , Etc.
C) Microscopic – Casts, Bacteria, Etc….
 The easiest and most common type of preservation is refrigeration of the urine specimen at 4 -
6°C within 2 hours of collection if the specimen is not able to be tested right away.
 Timed urine collection may require the use of preservatives e.g: Boric acid, Thymol, Glacial acetic
acid, Formalin, Sodium carbonate. Thymol,

23. Cerebrospinal fluid (CSF)
 Examination of CSF is an essential step in the diagnosis of any patient with evidence of meningeal irritation or
affected cerebrum.
 Almost 3-10 ml of CSF is collected and part of it is used for biochemical, immunological and microscopic
examination and remaining for bacteriological or fungal examination.
The important precautions for CSF collection and transportation:
a. Collect CSF in a screw – capped sterile container and not in an injection vial with cotton plug.
b. Do not delay transport and laboratory investigations.
c. Transport in a transport medium if delay in processing is unavoidable.
d. CSF is a precious specimen, handle it carefully and economically. It may not be possible to get a repeat specimen.
e. Perform physical inspection immediately after collection and indicate findings on laboratory requisition form.
f. Store at 37oC, if delay in processing is inevitable.

24. STOOL SAMPLE COLLECTION
A stool sample is collected for one or more tests, depending on your healthcare provider’s
order.
 You may use the same bowel movement for more than one test. For each test:
 Unscrew the lid from the specimen container. Set aside.
 Prepare the collection container (clean shallow pan, plastic bag or clear plastic wrap) in which you
will collect your sample.
 Collect the sample. Do not collect stool that has been mixed with water or urine.
 Using the plastic spoon attached to the lid, scoop out samples from bloody, slimy or watery areas
of the stool (if present). If the stool is hard, select areas from each end and the middle of the stool.
 Transfer enough of the selected stool to the orange- and green-cap specimen containers to raise the
level of liquid to the “fill to here” line. Do not overfill.
 Screw the lid back on the container. Make sure it is closed tightly. Shake to mix.
 Place the specimen container in a zip-close bag and seal it.

25. Transportation of specimens
 Specimens to be sent to other laboratories require
 special attention for safe packing of the material.
 Guidelines are usually issued by national authorities and the same should be strictly
followed.
 For hand-carried transportation over a short distance, the specimen should be placed upright
in appropriate racks.
 For long distance transportation, it should be placed in three containers

26. For long distance transportation
 A primary container which has the specimen and is leak proof with a screw-cap.
 A secondary container which is durable, waterproof and made of metal or plastic with a screw-cap. It should have enough
absorptive material to absorb the contents of the primary container should the latter break or leak. On its outside, the
details of the specimen should be pasted.
 A tertiary container is usually made of wood or card box. It should be capable of withstanding the shocks and trauma of
transportation. Dry ice can be kept between this and the secondary container along with sufficient absorbents and
provision for the escape of carbon dioxide to prevent a pressure build-up inside.

27. SAMPLE REJECTION
Sample rejection criteria for clinical samples
 Missing or inadequate identification.
 Insufficient quantity.
 Specimen collected in an inappropriate container.
 Contamination suspected.
 Inappropriate transport or storage.
 Unknown time delay.
 Haemolysed blood sample.

28. Brekle B, Hartley J (2014) Specimen Collection: Microbiology and Virology. Bit.ly/GOSHSpecimen
Campbell JD, Skubitz APN, Somiari SB et al. (2008). International Society for Biological and Environmental
Repositories (ISBER). 2008 Best practices for repositories: collection, storage, retrieval and distribution of biological
materials for research. Cell Preserv Technol, 6:3–58.
Falster C, Poulsen SS, Ferløv-Schwensen S. (2020) Urine samples produced at patients’ own home rarely meet
recommendations for analysis. Dan Med J.67(4):A08190475.
Giavarina D, Lippi G. (2017) Blood venous sample collection: Recommendations overview and a checklist to improve
quality. Clin Biochem.;50 (10-11):568-573.
Guder WG, da Fonseca-Wollheim F, Heil W, Müller-Plathe O, Töpfer G, Wisser H, et al. (1996) Wahldes optimalen
Probenvolumens. Klin Chem Mitt; 27: 106-7.
Malami D.T and Salisu G., (2005). Laboratory diagnostic services, (2):2.
Queremel Milani D.A, Jialal I. Urinalysis. [Updated May 8,2022]. In: StatPearls [Internet]. Treasure Island (FL):
StatPearls Publishing; 2022 Jan. Accessed September 6, 2022.
References