Process of SCT

• Good quality sputum collection is of paramount importance in tuberculosis diagnosis.
• Once a person is identified as presumptive TB, s/he is referred to the Designated Microscopy Centre (DMC) for sputum collection.
• For TB diagnosis two sputum samples are collected - one is the supervised ‘spot’ sample collected at the DMC (labelled Specimen A) and the other is the early morning sample collected by patient themselves at his/her home (labelled Specimen B).
• If the patient is coming from a long distance or s/he is unlikely to return to give the second specimen, two spot specimens may be collected with a gap of at least one hour.

Figure: Flowchart for Sputum Collection and Transport

Sputum Collection

• The (NTEP) request form required for the biological specimen examination need to be filled.
• The Lab Technician (LT) should instruct the patient to thoroughly rinse the mouth with clean water and demonstrate to inhale deeply 2-3 times and cough out the sputum from the depth of the chest into a sterile 50 ml sputum container, in a well-ventilated space.
• After collecting the sputum, close the lid of the containers and wipe the surface of the tube with 5% phenol to disinfect and allow it to air dry.
• Label the tubes with patient details, date and time of collection, specimen identification, lab no. using a permanent marker.

Sputum Transport

• The sputum collected should be transported immediately to the Nucleic Acid Amplification Testing (NAAT)/ Culture and Drug Susceptibility Testing (C&DST) laboratory. In case of any unavoidable delays, the sample should be refrigerated.
• The programme mandates triple layer packaging for the transport of the sputum specimens.
• Firstly, seal the joint between the cap and neck of the sputum containers with a parafilm strip (primary receptacle package).
• Wrap the sputum containers individually in absorbent cotton, place them in a zip lock pouch and secure them with a rubber band (secondary receptacle package).
• Fold and place the NTEP request form in another zip lock pouch.
• Place the zip lock pouch with sputum containers in a thermocol box along with two pre-frozen coolant gel packs and the zip lock pouch with the NTEP request form is placed on top.
• The dimensions of the thermocol box used for sputum transport are: thickness - 2.5 cm; Outer dimensions: length - 18.5 cm, breadth - 13 cm, height - 12 cm (without lid), height -14 cm (with lid); Inner dimensions: length - 14.5 cm, breadth - 8 cm, height - 12 cm (without lid), height - 13 cm (with inner part of lid).
• The coolant gel packs should be conditioned in the deep freezer in a temperature between -20 to -15^o C for a minimum 48 hours to a maximum 72 hours before use so that they can maintain a temperature between 12-20^o C for up to approximately 48 hours in tightly packed thermocol boxes while the average outside temperature is 35^o C. 
• Seal the thermocol box with duct tape and affix ‘To’ and ‘From’ address, biohazard sticker on the box (tertiary receptacle package).
• Weight of the fully packed consignment box should be up to 400 grams and the thermocol boxes and gel packs should not be reused. 
• Transport the box through NTEP identified courier/ speed post service.

Resources

• Training Module (1-4) for Programme Managers and Medical Officers, NTEP, MoHFW, 2020.
• Guidelines for Programmatic Management of Drug-resistant TB in India, 2021.
• Module for Laboratory Technician, CTD, MoHFW, India, 2005.

Assessment