Problems encountered in clinical anaerobic bacteriology.

Despite the rapid progress made in the technology of anaerobic bacteriology during the last 15 years, substantial variation in the practices and resources of different laboratories still exists. All steps, from the collection of the specimen to final identification, may involve pitfalls. Aspirated pus and tissue samples that are anaerobically transported are always preferable to swabs. Failure to examine gram-stained preparations and wet mounts and to inoculate the specimen promptly onto fresh supplemented media, including selective media, is still common. Generating and maintaining anaerobiosis requires careful monitoring. Plates often are discarded prematurely. The results of final identification with PRAS (prereduced, anaerobically sterilized) biochemicals and gas-liquid chromatography usually arrive too late to guide the clinician to proper therapy. Preliminary tests, along with growth on selective and differential media, are essential for prompt identification of clinically significant anaerobes. Future efforts should be directed toward diminishing the heavy work load of anaerobe laboratories by developing simpler and more rapid procedures.