ThermoScientificTM OxoidTM CAZ10 ceftazidime, CT1629B antimicrobial susceptibility test disc – potential for false resistance results if stored at the wrong temperature

Manufactured by Oxoid Ltd (ThermoFisher Scientific) – antibiotic (ceftazidime) concentration may decrease over time if test disc is stored between 2°C and 8°C: only specific lots are affected (MDA/2017/034)


  • Ensure all relevant members of staff receive the manufacturer’s Field Safety Notice (FSN) and that they understand the problem and the actions to be taken.
  • Destroy all affected lots (listed in the FSN) and contact Thermo-Fisher customer services / local distributor for replacements.
  • Discs that have been stored between -20°C and 2°C remain unaffected for the entire shelf life (36 months).
  • If concerns exist after repeat testing, alternative methods of establishing ceftazidime susceptibility should be used.
  • As part of your review processes, report any incorrect results to MHRA via Yellow Card or the relevant devolved administration.

Action by

  • Directors of pathology
  • Laboratory managers
  • Microbiologists
  • Lead biomedical scientists (microbiology)

Deadlines for actions

Actions underway: 7 December 2017 Actions complete: 21 December 2017

Manufacturer contacts

Martyn Rogers
Thermofisher Scientific
Wade Road
RG24 8PW
Telephone: 01256 694 245


If you are responsible for cascading these alerts in your organisation, these are our suggested distribution lists.

Trusts (NHS boards in Scotland)

CAS and NICAS liaison officers for onward distribution to all relevant staff including:

  • Clinical pathology directors
  • Infection prevention and control directors
  • Medical directors
  • Microbiologists
  • Purchasing managers
  • Supplies managers

Public Health England

Directors for onward distribution to:

  • PHE laboratories
  • Laboratory managers
  • Regional microbiologists
  • Risk manager

Independent distribution

Establishments registered with the Care Quality Commission (CQC) (England only)

  • Hospitals in the independent sector
  • Independent treatment centres

Please note: CQC and OFSTED do not distribute these alerts. Independent healthcare providers and social care providers can sign up to receive MDAs directly from the Department of Health’s Central Alerting System (CAS) by sending an email to: and requesting this facility.



Send enquiries about this notice to MHRA, quoting reference number MDA/2017/034 or 2017/009/007/601/006.

Technical aspects

Rehad Abdool Gaffoor, MHRA

Tel: 020 3080 6459

Clinical aspects

Devices Clinical Team, MHRA

Tel: 020 3080 7274

Reporting adverse incidents in England

Through Yellow Card

Northern Ireland

Alerts in Northern Ireland are distributed via the NI SABS system.

Enquiries and adverse incident reports in Northern Ireland should be addressed to:

Northern Ireland Adverse Incident Centre, CMO Group,
Department of Health, Social Services and Public Safety

Tel: 028 9052 3868


Northern Ireland Adverse Incident Centre (NIAIC)

Please report directly to NIAIC using the forms on our website.


Enquiries and adverse incident reports in Scotland should be addressed to:

Incident Reporting and Investigation Centre,
Health Facilities Scotland,
NHS National Services Scotland

Tel: 0131 275 7575

Fax: 0131 314 0722


Reporting adverse incidents in Scotland

NHS Boards and Local Authorities in Scotland – report to Health Facilities Scotland.

Contractors such as private hospitals carrying out NHS work and private care homes that accept social work funded clients – report to Health Facilities Scotland.

Private facilities providing care to private clients report to the Care Inspectorate and MHRA.


Enquiries in Wales should be addressed to:

Healthcare Quality Division,
Welsh Government

Tel: 02920 823 624 / 02920 825 510


Reporting adverse incidents in Wales

Report to MHRA through Yellow Card and follow specific advice for reporting in Wales in MDA/2004/054 (Wales).

Download documents

MDA/2017/034 - ThermoScientificTM OxoidTM CAZ10 ceftazidime, CT1629B antimicrobial susceptibility test disc – potential for false resistance results if stored at the wrong temperature

Published 23 November 2017