The goal of microbiologic evaluation is to provide accurate, clinically pertinent results in a timely manner. The quality of the specimens submitted to the microbiology laboratory is critical for optimal specimen evaluation.
The general techniques of specimen collection and handling that have been established both to maximize the yield of organisms and isolate relevant pathogens from specimens obtained from different body sites will be reviewed here (table 1A-D). The techniques of collecting specific specimens such as blood, sputum, and urine are discussed in more detail separately. (See "Blood cultures for the detection of bacteremia" and "Sputum cultures for the evaluation of bacterial pneumonia" and "Sampling and evaluation of voided urine in the diagnosis of urinary tract infection in adults".)
Valid interpretation of the results of culture can be achieved only if the specimen obtained is appropriate for processing. As a result, care must be taken to collect only those specimens that may yield pathogens, rather than colonizing flora or contaminants. Specific rules for the collection of material vary, depending upon the source of the specimen, but several general principles apply [1-3]:
●Make every effort to obtain specimens prior to the initiation of antimicrobial therapy.
●Wear gloves, gowns, masks, and/or goggles, when appropriate, when collecting specimens from sterile sites. Use strict aseptic technique.