inforMED
MalfunctionMZP

KIT COBAS 58/68/8800 MPX 480T US

Received Dec 29, 2025 · Event occurred Dec 4, 2025

Report 2243471-2025-05353 · MDR key 23906107

Device

Generic name

Assay, Hybridization And/or Nucleic Acid Amplification For Detection Of Hepatiti

Catalog number

09040854190

Lot number

M02951

Product problems

  • False Positive Result
  • Incorrect, Inadequate or Imprecise Result or Readings
  • False Positive Result
  • Incorrect, Inadequate or Imprecise Result or Readings

Patient

NA · Unknown

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

Narrative

Description of Event or Problem

THERE WAS AN ALLEGATION OF DISCREPANT FALSE-POSITIVE HBV RESULTS WHEN USING THE COBAS® MPX (480T) ON THE COBAS 5800 FOR TESTING ON 12 IDT SAMPLES. ALL OF THE SAMPLES WERE INITIALLY REACTIVE, BUT WHEN REPEATED, THE RESULTS WERE NON-REACTIVE. THERE WERE NO REACTIVE RESULTS USING SEROLOGICAL TESTS.

Additional Manufacturer Narrative

THE COBAS 5800 SERIAL NUMBER WAS (B)(6). THE INVESTIGATION IS ONGOING.

Additional Manufacturer Narrative

THE INVESTIGATION WAS UNABLE TO FIND A PRODUCT PROBLEM. THERE WAS NO EVIDENCE OF A PRODUCT QUALITY ISSUE WITH THE REAGENTS OR THE SYSTEM. OVERALL, THE DATA WAS CONSISTENT WITH THE CONCLUSION THAT THE DONOR MAY HAVE AN EARLY INFECTION OR A CHRONIC HBV INFECTION WHERE THE VIRUS WAS PRESENT IN THE LIVER AND BLOOD, BUT REPLICATION WAS AT A LOW LEVEL. CHRONIC CARRIERS CAN HAVE FLUCTUATING LEVELS OF HBV DNA, SOMETIMES RESULTING IN LOW VIRAL LOADS.