A turbid cup, four hours late

A sterile cup arrives at the bench. The label carries the required patient identifiers and specimen source, and receipt time is documented. The requisition says clean-catch midstream. The problem is the clock: the void was reported four hours ago, the cup sat at room temperature the whole time, it was never light-protected, and it is now visibly turbid.

Before a single strip pad or field of view is read, a laboratory professional has to answer a prior question. Can this specimen still answer the question it was collected to answer? Turbidity alone does not prove infection, and a normal-looking pH does not prove the specimen is fresh. The condition of the specimen sets the ceiling on how much the analytical result can be trusted.

The reasoning behind that ceiling is: what collection purpose was intended, what changes during delay and light exposure, and how a written acceptance policy turns those facts into one of four actions: accept, reject and recollect, or release with a qualifying comment.

Read the specimen's history before you read its result.