The culture smear (smear made from isolates) is used to determine the staining characteristics, size, shape, and cellular arrangement of the unknown organism(s). This data helps the microbiologist to decide on additional culture and identification methods.
By correlating the Gram stain reaction, size, shape, and cellular arrangement of the organism with colony morphology and growth requirements, the microbiologist may be able to tentatively identify the organism. This information may help the physician to optimize treatment until definitive culture and antibiotic susceptibility results become available.
Gram stain reaction and bacterial shape must be included in the report.
The cellular arrangement is not always included in the posted report since it may vary depending on the culture medium (liquid or solid) used to isolate the organism. (However, the cellular arrangement should be noted on any internal work cards or electronic work cards. This information may be useful to the microbiologist.) For certain organisms, the size of the organism may be "described" as tiny, large, and so on, but is an optional element. Always report based on the procedure of your laboratory.
The following seven pages contain additional ungraded practice questions pertinent to the material covered.
