inforMED
MalfunctionJIL

COMBUR 10

Received Nov 12, 2025 · Event occurred Oct 20, 2025

Report 1823260-2025-04597 · MDR key 23532134

Device

Generic name

Urine Test Strips

Manufacturer

Roche Diagnostics

Catalog number

09587624190

Lot number

84639701

Product problems

  • False Negative Result
  • Incorrect Measurement
  • False Negative Result
  • Incorrect Measurement

Patient

NA · Unknown

  • No Clinical Signs, Symptoms or Conditions
  • No Clinical Signs, Symptoms or Conditions

Narrative

Additional Manufacturer Narrative

ROCHE DIAGNOSTICS INITIATED A ROOT CAUSE INVESTIGATION. IT WAS FOUND THAT ONE OF THE THREE EXPECTED STRIP LAYERS WAS MISSING FROM THE COMBUR10 TEST M STRIP LOT 84639701. THEREFORE, THE EXPECTED COLOR FOR LEUCOCYTES CANNOT DEVELOP, AND THE COBAS U 411 WILL DISPLAY A FALSE NEGATIVE RESULT FOR A POSITIVE SAMPLE. THE US IS NOT IMPACTED BY THE ISSUE DESCRIBED WITH COMBUR10 TEST M STRIP LOT LOT 84639701.

Additional Manufacturer Narrative

THE ANALYZER SERIAL NUMBER IS (B)(6). THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THERE WAS AN ALLEGATION OF QUESTIONABLE COMBUR 10 LEUKOCYTE RESULTS FOR AN UNKNOWN NUMBER OF PATIENT SAMPLES ON A COBAS U 411 URINE ANALYZER. THE TEST STRIPS SHOW NO SIGNS OF LEUKOCYTES, EVEN THOUGH LEUKOCYTES ARE MASSIVELY PRESENT (> 100 LEUKOCYTES/UL) UNDER THE MICROSCOPE.