Anaerobes

Anaerobes can be complex depending on the source of the specimen. For typically sterile sites like a pleural fluid or pericardial fluid, any growth on anaerobic media would be worked up fully. Sites with mixed/normal anaerobic flora such as stools, sinuses, and respiratory sites become complicated.

To effectively read an anaerobic culture, the technologist needs to know what flora is considered normal for that site and be able to isolate the potential pathogen from a mixed culture. Subculturing and isolation of anaerobic organisms can be technically challenging. In mixed anaerobic cultures, subculturing from a well-isolated colony is the most sensible first step. Depending on your laboratory’s procedure, you may also need to do an aerotolerance test. MALDI-TOF should be performed according to your laboratory’s procedure. A mistake in subculturing at this point may result in a delay of two days or more.