Presentation on theme: "Collecting and transporting sputum specimens"— Presentation transcript:
1Collecting and transporting sputum specimens Module 3:Collecting and transportingsputum specimensGlobal Laboratory Initiative – Xpert MTB/RIF Training Package
2World Health Organization Contents of this module1 April, 2017Choosing suitable specimen containersTiming of specimen collectionHow to collect a specimenHandling specimens and referring them for testingLabelling specimens
3Learning objectives At the end of this module, you will be able to: Describe specifications of suitable containers for sputum collectionDiscuss different sputum collection strategies: spot/morning/spot, spot/spot, single spot for Xpert MTB/RIFDescribe and demonstrate safe and correct collection of sputumDescribe options for specimen collection, handling and transportList features of a good quality sputum specimenOutline requirements for a properly labelled specimen
4Sputum-specimen collection: container specifications Adapt according to the NTP’s guidelines in your country30-50 ml capacityTranslucent or clear materialSides and walls that allow easy labellingSingle-use combustible materialLeak-proof with a screw-capWide mouth
5Sputum specimen collection: timing World Health Organization1 April, 2017Sputum specimen collection: timingSpot–morning–spotWHO and The Union recommend this timing:Spot In the clinic – during the initial visitEarly morning At home – first sputum produced in the morning on the day of the second visit to the clinic (ideally, the day after the initial visit)Spot In the clinic – additional sputum collected during the second visit.
6Collection strategies: spot-morning-spot AdvantagesA spot specimen is available in case the patient does not return with the morning specimen.DisadvantagesRequires two visits to the clinic.Diagnosis takes at least 2- 3 days.Increases the workload.There is a high risk of missing a case if only the first specimen is received.
7Collection strategies: WHO’s revised policy WHO’s policy on case detection by microscopy was revised in 2007:The recommended number of specimens examined was reduced from three to two in countries with appropriate external quality assurance (EQA) procedures and documented good quality microscopyIn these settings, the case definition was also revised to one AFB positive smear, defined as one or more acid-fast bacilli in at least 100 microscopic fieldsIf appropriate quality assurance is not available, three specimens should be examined.
8Same-day strategy: spot-spot Good quality microscopy of two consecutive sputum specimens (spot-spot) identifies 95–98% of smear- positive TB patients.Advantages – this strategy:Greatly reduces the workload of laboratoriesHas the potential for offering same-day diagnosisIs better for patients because it reduces the number of visits while largely maintaining sensitivity.Disadvantages:Very minor loss in the number of cases detected.
9Sputum collection: overview Follow the NTP’s guidelines on sputum collection.Ensure that sputum collection is supervised.A single sputum specimen is recommended for Xpert MTB/RIF:Increased yield is obtained by testing multiple specimens but this increases the cost of testingAn additional sputum specimen may be needed in case of an error or invalid Xpert MTB/RIF resultAt least 1 ml of sputum should be collected.Additional sputum specimens may be needed for microscopy, culture and DST, depending on the NTP’s guidelines (Xpert MTB/RIF is not recommended for monitoring patients’ treatment).Avoid using pooled sputum specimens.
10The NTP’s guidelines for sputum collection in (country name) [Insert the NTP's specific guidelines]To be customized by each country
11Sputum collection: safety When providing a sputum specimen, a patient may produce infectious aerosols and therefore biosafety precautions are needed:Instruct the patient to cover his or her mouth when coughingNever collect sputum in the laboratoryCollect sputum away from other people in a well ventilated space following the NTP’s guidelinesDo not stand in front of the patient during specimen collection!
12Sputum collection: Patient education and instructions The best specimen comes from the lungs.Saliva or nasal secretions are unsatisfactory.Specimens should not contain food or other particles because the test may not work properly.Patients should be instructed to take the following steps to produce the best specimen:Wash your mouth with clean water to remove food and other particlesInhale deeply 2–3 times and breathe out strongly each timeCough deeply from your chest to produce sputumPlace the open container close to your mouth to collect the specimen; do not get sputum on the outside of the containerWash your hands after collecting the sample.
13Specimen quality: Optimal quality MucoidPurulent(Images courtesy of A. Van Deun)
14Specimen quality: Suboptimal quality BloodstainedSalivary(Images courtesy of A. Van Deun)
15Specimen quality: overview Obtaining an adequate quantity of good quality sputum is critical to ensuring accurate test results. For best results, obtain 1-4 ml of purulent/mucoid sputum.
16Request for sputum examination A request for sputum examination should include the:Name of the treatment unitDate of the requestPatient's information (that is, name, sex, age, address and the register number of the patient or suspected case)Number of specimens and types of specimens sent for testingDate the specimens were collectedReason for examination (for example, diagnosis or follow-up)Signature of the person requesting the examination.
17Laboratory request form (example) (1 of 2) To be customized by each country.Add your local request form, and show participants how to correctly complete the form.
18Laboratory results form (example) (2 of 2) To be customized by each country.Add your local request form, and show participants how to correctly complete the form.
19Labelling the specimen container Label with the patient’s name, identification number and the date of collection.Label the outer sides of the container with permanent ink.Never label the lid.
20Receiving specimens in the laboratory Check the quantity and quality of specimens:Check the volume (ideally 1-4 ml; a minimum of 1 ml is required for Xpert MTB/RIF testing)Record sputum consistency (mucoid, purulent, bloody or watery) on the report formEnsure that specimens do not contain food or other particulates.Check that the patient’s information is complete, and that Xpert MTB/RIF testing has been requested in accordance with the NTP’s guidelines.Follow the NTP’s guidelines for rejecting samples.Ensure that the patient’s information is complete on both the request form and the specimen container, and ensure that the information matches.Record the specimen in the laboratory register and allocate a laboratory serial number to the specimen.
21If patients are referred If specimens are referred Referral systemsPeripheral facilities that do not perform Xpert MTB/RIF testing should refer either patients or specimens to a testing laboratory.If patients are referredIf specimens are referredAdvantagesSputum collection can be monitored and collection can be repeated if the first specimen is not satisfactory.Treatment can be initiated faster.Patient does not have to travel.DisadvantagesRequires patients to travel.Requires systems for safe transport and shipment.Requires efficient system for transmitting results.Specimen transport may require cold-chain or preservatives.
22Specimen referralThe shipment of specimens constitutes a public-health risk, and the shipper is responsible for ensuring that samples are packed safely.Triple packaging (described in later slides) must be used:Locally appropriate solutions can be used as long as safety requirements are met.Country-specific safety guidelines must be followed in order to correctly categorize the specimen and its associated risk (eg, Category A or B, as per WHO Guidance on regulations for the transport of infectious substances, 2013–2014).To be customized by each country
23Transporting specimens To be customized by each countrySpecimens should be transported to a laboratory as quickly as possible:A sputum specimen that has been delayed during transport can still be used for microscopy and Xpert MTB/RIF testing.Whenever possible, specimens should be refrigerated at 2–8°C for a maximum of 10 days. However, if necessary, specimens can be stored at a maximum of 35°C for up to 3 days, and then refrigerated at 2–8°C for a combined maximum duration of 10 days.The total number of specimens in a box must correspond to the number of accompanying request forms.The identification number on each sputum container must correspond to the number on a request form.The accompanying forms must contain the required information for each patient.
24Triple packaging: Step 1 of 3 Primary packagingWrap the leak-proof container in cotton wool or paper towels in a sufficient quantity to absorb the entire contents in case of leaks.
25Triple packaging: Step 2 of 3 Secondary packagingPlace the wrapped container inside a secondary container, such as a self- sealing plastic bag or another container.Place the secondary container in a rack to prevent leakage.
26Triple packaging: Step 3 of 3 Tertiary packagingPlace the secondary container and its contents in an approved safety cooler box or another appropriate container in an upright position.Place a biohazard sign – with markings and labelling appropriate for the specimen category – on the tertiary container.
27Role play: Sputum collection PurposesTo practise educating a person suspected of having TB about the importance of a properly collected sputum specimen and to practise providing instructions on how to collect a specimenTo practice packaging sputum specimens for referral.Total time40 minutes.ProcessWork in groups of 4.Choose roles: health worker, person suspected of having TB, dispatcher and observer.The health worker instructs the person suspected of having TB on how to produce a specimen, and then provides the specimen to the dispatcher for packaging; the observer provides feedback.Switch roles and repeat the process until everyone has played each part once.
28Role play: DebriefDid the health-care worker follow appropriate procedures?COMPLETE a Request for Sputum Examination formLABEL the sputum containersEXPLAIN to the person suspected of having TB how to collect sputum and the importance of a properly collected specimenASK the person suspected of having TB to produce a first sampleASK the person suspected of having TB to collect another sample the next morning and then bring it to the diagnostic centre (OR modify the advice to follow the NTP’s guidelines)PACKAGE appropriately the sputum sample for referral.Did the person suspected of having TB understand the instructions?Did the dispatcher receive the package appropriately and complete the administrative procedures correctly?What suggestions for improvements did the observer note?
29SummaryNot all containers are suitable for specimen collection: follow the NTP’s guidelines on the size or volume of the container to be used, and the material and type of lid.An adequate quantity (1-4 ml) of good quality sputum (that is, purulent/mucoid) as well as a properly completed Laboratory Request Form and properly labelled specimen containers are critical to ensuring accurate results from the Xpert MTB/RIF test.Patients should be educated on how to produce good quality specimens, and sputum collection should be supervised.A well functioning referral system (for patients or specimens, or both) is critical to ensuring a high quality diagnostic service: follow country-specific safety guidelines for storing and shipping samples; triple packaging must be always used.
30AssessmentWhat are the the NTP’s guidelines for collecting sputum specimens in your country?Why should sputum never be collected in a laboratory?What are the options for referral at peripheral health centres that do not perform the Xpert MTB/RIF test?What are the features of a good quality specimen?How should a sputum container be labelled?What supplies are needed for triple packaging for TB diagnostic samples?