Sputum microbiology

Includes BAL, aspirate, brushings and washings, ETT samples.

Test indications

  • Investigation of suspected bacterial infection
  • Suspected Legionella infection
  • Suspected Mycobacteria infection (see TB culture).

Test information

Microbiological investigations of sputum include:

  • routine culture
  • Legionella

State recent antibiotic therapy.

State any underlying chest disease, especially if chronic: cystic fibrosis, bronchiectasis, COAD.

State duration of current symptoms.

Send paired sera for serology for mycoplasma, chlamydia, viral causes and Legionella as indicated by clinical picture.

Samples required

Collect in sterile universal container.

Ensure specimen comprises sputum (not saliva or food). A specimen collected at physiotherapy is preferable.

Induced sputum or bronchial washings are needed for PCP PCR and are referred to Micropathology Ltd., University of Warwick Science Park Venture Centre, Coventry CV4 7EZ.

Nasopharyngeal aspirate is required for RSV.

Turnaround time

Sputum - routine culture: 3 working days

BAL: 3 working days

Legionella culture: working 10 days

Quoted turnaround times are the time from receipt of specimen into the laboratory to 90% of reports leaving the laboratory. Stated times are based on normal working hours, Monday to Friday, excluding statutory bank and public holidays.