It was an otherwise ordinary Tuesday morning when a patient arrived at the laboratory to drop off a urine specimen. The patient proudly handed over a glass jar, explaining that they had collected the sample at home and made sure the container was clean. The technologist took one look and noticed a familiar label: MAYONNAISE – REAL MAYO. Apparently, the patient had decided that an old mayonnaise jar would work just as well as a proper urine collection cup.
Things got even more interesting when the technologist opened the jar. There was, unmistakably, a little mayonnaise residue still clinging to the sides. The smell was equally impressive. For a brief moment, the laboratory felt less like a clinical testing facility and more like the sandwich counter at a neighborhood deli. One technologist reportedly wondered if the patient had accidentally ordered a urinalysis with a side of potato salad.
When the patient was contacted about the specimen, they seemed genuinely puzzled. “But I washed it out really well!” they insisted. The technologist patiently explained that urine specimens must be collected in appropriate containers to avoid contamination and unreliable results. The patient then asked, “Even if it’s just a little mayonnaise?” Unfortunately, mayonnaise is not an approved specimen preservative, and the laboratory had no established reference range for sandwich spread.
The specimen was rejected, a proper collection cup was provided, and the patient was asked to recollect. The laboratory staff eventually returned to their normal duties, although one technologist suggested adding a new reminder to the collection instructions: “Please do not submit specimens in food containers, regardless of how thoroughly they’ve been washed.” After all, we’re a clinical laboratory, not a deli!
Submitted by:
Karen Mitchell
Lab Receptionist
North Dakota, USA
