Why are all proficiency testing specimen answers reported and quantitated, while clinical specimen reports are rarely quantitated in terms of organism numbers?
There are two issues to consider. (1) When reporting proficiency testing (PT) specimen results, you are asked to quantitate organisms in both the formalin wet mounts and permanent stained smears. This information serves as a quality control check for the proficiency testing agency to ensure that organism numbers are consistent throughout the challenge vials/slides. (2) Most laboratories (with few organism exceptions) do not quantitate organisms on the concentration or permanent stained smear reports. Some exceptions might be: Trichuris trichiura eggs in a concentration wet mount (light infections might not be treated). Since many organisms are shed on a random basis, quantitation may change dramatically from day to day and generally has little clinical relevance.
