An ikterische Probe is a sample whose serum or plasma shows a strong yellow, orange or brownish colour instead of the usual pale straw tone. The colour comes from bilirubin, the pigment produced when red blood cells are broken down and normally processed by the liver. When more of it circulates than usual, it is visible in the separated sample long before anyone would notice anything about the person who gave it.
The laboratory records the discolouration for a technical reason. Bilirubin absorbs light in a range that several photometric methods also use, so a strongly coloured sample can push individual measurements up or down depending on the method. Modern analysers quantify the colour as an index alongside the results, which is why the comment on a report is a measured statement about the specimen rather than an impression. Depending on the analyte, the laboratory then releases the value with a note or holds it back and asks for a new sample. Where a result is held back, the akkreditiertes Labor states what it needs, and that requirement is not open to discussion at the counter.
What this means for a pharmacy is close to nothing in clinical terms and quite a lot in terms of communication. The pharmacy did not observe the discolouration, does not assess it, and cannot say what caused it. Bilirubin rises for a long list of reasons, some of them entirely benign and lifelong, others not, and separating them requires a physician with the history in front of them. The correct handling is to pass on the laboratory comment in the words the laboratory used, to say plainly that it describes the sample, and to recommend that the person take the report to their physician. Speculating about causes at the counter is out of place and, if the guess is wrong in either direction, actively harmful.
It is worth grouping the term with its two neighbours. Hämolyse and the lipämische Probe are the other two interference findings that appear as standing comments on laboratory reports, and all three describe the specimen rather than the patient. They differ in where they arise. Haemolysis is usually caused during collection and handling, lipaemia usually by a recent meal, while an icteric sample reflects something about the person and is not a Präanalytik error at all. That distinction matters, because a repeat draw fixes the first two and changes nothing about the third.
This glossary entry is general information about German pharmacy law and practice. It is not legal advice. For binding guidance on your own pharmacy, contact your Landesapothekerkammer.
