Sputum, BALs and Tracheal Aspirates
  1. Samples should only be forwarded to the laboratory if they show evidence of purulent material. If the patient has provided saliva or if there are visible food particles, it is better to start again straight away. Better samples may be forthcoming early in the morning (but before breakfast !), or with the assistance of a physiotherapist.
  2. The microbiological quality of sputum deteriorates rapidly. Day-old specimens seldom provide any useful result.
  3. In patients with pneumonia, blood cultures should always be taken, and consideration also given to establishing a diagnosis by means of antigen detection and serology.
  4. Induced sputum and broncho-alveolar lavage (BAL) specimens should reach the laboratory as a matter of urgency, preferably having alerted the staff there in advance. The request form should give precise details of the clinical background and investigations required, or the case discussed with the duty doctor.
Investigation Culture and sensitivity

Gram stain if required
Inform lab before sending No (unless urgent)
Specimen type Sputum, BALs and Tracheal Aspirates
Ideal time to take specimen see above
Specimen container
Sterile leak proof container
Please note that Bronchial lavages (BAL) specimens MUST NOT be sent with the ‘tube lids’. These ‘BAL’ tube lids are prone to leakage, and constitute an unacceptable level of infection risk to porters and other staff. ‘Tube lids’ MUST be replaced with a proper sealed specimen lid.
Please note that sputum pots with metal lids are generally less inclined to suffer leakage than sputum pots with plastic lids. Metal lids on large diameter specimen pots seal more effectively. Plastic lids have been known to loosen and leak if the pot is subject to temperature changes before reaching the laboratory.
Labelling requirements click here
Transport to the laboratory If transport is delayed then refrigerate sample. Delays of over 48 hours are undesirable
Turnround 48 - 72 hours (Where fungal culture is requested this may be extended to 14 days)
Additional information Please ensure that all request forms are clearly labelled with patient details, relevant clinical information and the tests required
Specimen retention Please ensure that any requests for additional investigations on the specimen are made within 7 days from the date of the original request


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